WO2025016567A1 - Metallocenes for the manufacture of propylene copolymers - Google Patents

Abstract

The disclosure relates to process for producing a propylene copolymer resin, comprising polymerizing propylene and at least one comonomer selected from ethylene and C₄-C₁₀ alpha olefin comonomers; wherein the process is carried out in presence of a polymerization catalyst comprising, (i) a metallocene complex of formula (I); (ii) a cocatalyst system comprising a cocatalyst comprising a group 13 element; and (iii) optionally a support. wherein the metallocene complex of formula (I) is wherein Mt is Zr or Hf; X is a sigma ligand; R¹ are each independently, same or different from each other, C₁-C₂₀ hydrocarbyl, optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or form together with the Si atom they are attached to a C₄-C₈ ring; R² and R^2' are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H, linear or branched C₁-C₆-alkyl, C₃-C₈-cycloalkyl, or a C₆-C₉-aryl, provided that R² and R^2' are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, C₇-C₂₀-arylalkyl, C₇-C₂₀-alkylaryl, C₆-C₂₀ aryl, or -OR³¹, with R³¹ being C₁-C₁₀-hydrocarbyl, whereby at least one R₃ per phenyl group and at least one R⁴ is not H; R⁵ and R⁶ are each independently, same or different from each other, C₁-C₁₀ hydrocarbyl, or may form together with the C atoms they are attached to a C₅-C₇ carbocycle; R^51' is C₁-C₁₀-hydrocarbyl; and R^6' is C(R⁶¹)₃, with R⁶¹ being linear or branched C₁-C₆-alkyl.

Description

METALLOCENES FOR THE MANUFACTURE OF PROPYLENE COPOLYMERS FIELD OF THE DISCLOSURE The present disclosure relates to new bisindenyl ligands, complexes thereof, and catalysts comprising those complexes. The present disclosure also relates to the use of the new bisindenyl metallocene catalysts for the production of polypropylene copolymers, especially with ethylene and/or butene, in particular propylene-ethylene-butene terpolymers, with high activity levels, high molecular weight, and hence low MFR, and with ideal melting points and sealing initiation temperatures. BACKGROUND OF THE DISCLOSURE Metallocene catalysts have been used to manufacture polyolefins for many years. Countless academic and patent publications describe the use of these catalysts in olefin polymerization. Metallocenes are now used industrially and polyethylenes and polypropylenes in particular are often produced using cyclopentadienyl based catalyst systems with different substitution patterns. Metallocene catalysts have been used also in the production of propylene-butene copolymers and propylene-ethylene-butene terpolymers. These copolymers and terpolymers are used especially for films, for example for blown or cast films, and to produce the sealing layer of multilayer BOPP films. These copolymers and terpolymers must have specific MFR2 values, such as MFR2 between 0.5 and 3 for blown films, 8-10 for cast films, and MFR2 matching that of the core hPP layer, typically MFR2 between 6 and 8, in the case of the sealing layer of multilayer BOPP films. The main advantage in using metallocene catalysts for producing propylene-butene copolymers and propylene- ethylene-butene terpolymers is that metallocene catalysts have a much higher reactivity for higher olefins like 1-butene and 1-hexene compared to Ziegler-Natta catalysts. On the other hand, in such copolymerization with metallocene catalysts the higher olefins tend to reduce the molecular weight of the copolymer, that is, increase its MFR2. Therefore, the amount of hydrogen used in such processes needs to be reduced, but this in turn leads to reduced catalyst productivities. Solutions to this problem have been described, for example, in WO2019215122 and in EP20193414 , in which a combination of two activators, namely methylaluminoxane and trityl tetrakis(pentafluorophenyl)borate, is used. WO2019179959 describes C₁-symmetric bisindenyl complexes comprising an indenyl moiety bearing 5-methoxy and 6-tert-butyl substituents and an indacenyl moiety bearing two aryl substituents on its 4,8 positions. The use of one of such metallocenes, formulated in silica catalysts containing both methylaluminoxane and trityl tetrakis(pentafluorophenyl)borate activators, has been described also for the production of propylene-butene copolymers in WO2023046573 and WO2023046824. It can sometimes be difficult to obtain high molecular weight e.g. propylene-butene copolymers and propylene-ethylene-butene terpolymers while maintaining desirable levels of catalyst productivity with such prior art catalysts. The present inventors thus sought to identify new metallocenes, which are able to provide high molecular weight e.g. propylene-butene copolymers and propylene-ethylene-butene terpolymers while maintaining desirable levels of catalyst productivity, especially in the case of the terpolymerization of propylene, in particular between propylene, butene, and ethylene. The desired catalysts should also have improved performance in high temperature polymerization, in particular in loop reactors. BRIEF DESCRIPTION OF THE DISCLOSURE An object of the present disclosure is to provide a new process for producing a propylene copolymer resin, comprising polymerizing propylene and at least one comonomer selected from ethylene and C4-C10 alpha olefin comonomers, that can be used to provide copolymer resins with sufficiently low MFR2 at desirable levels of productivity. The object of the disclosure is achieved by a process utilizing metallocene complexes of formula (I) which is characterized by what is stated in the independent claims. The preferred embodiments of the disclosure are disclosed in the dependent claims. It was surprisingly found that specific C1-symmetric metallocenes incorporating linear alkyl substituent larger than methyl on either one of or both 2-positions of the ligands, in combination with specific substitution of the other ligand positions, provide desired properties. DEFINITIONS Throughout the description, the following definitions are employed: The term “C1-C20-hydrocarbyl” includes C1-C20-alkyl, C2-C20-alkenyl, C2-C20-alkynyl, C3-C20- cycloalkyl, C3-C20-cycloalkenyl, C6-C20-aryl, C7-C20-alkylaryl, and C7-C20-arylalkyl groups or of course mixtures of these groups such as cycloalkyl substituted by alkyl. Unless otherwise stated, preferred C1-C20-hydrocarbyl groups are C1-C20-alkyl, C4-C20-cycloalkyl, C5-C20-cycloalkyl-alkyl groups, C7-C20-alkylaryl groups, C7-C20-arylalkyl groups, and C6-C20- aryl groups, especially C1-C10-alkyl groups, C6-C10-aryl groups, and C7-C12-arylalkyl groups, e.g. C₁-C₈ alkyl groups. Most especially preferred hydrocarbyl groups are methyl, ethyl, propyl, isopropyl, tert-butyl, isobutyl, C₅-C₆-cycloalkyl, cyclohexylmethyl, phenyl, and benzyl. The term “C₁-C₁₀-hydrocarbyl” includes C₁-C₁₀-alkyl, C₂-C_10-alkenyl, C₂-C₁₀-alkynyl, C₃-C_10- cycloalkyl, C₃-C₁₀-cycloalkenyl, C₆-C₁₀-aryl, C₇-C_10-alkylaryl, and C₇-C_10-arylalkyl groups or of course mixtures of these groups such as cycloalkyl substituted by alkyl. Unless otherwise stated, preferred C₁-C_10-hydrocarbyl groups are C₁-C_10-alkyl, C₄-C_10-cycloalkyl, C₅-C_10-cycloalkyl-alkyl groups, C₇-C_10-alkylaryl groups, C₇-C_10-arylalkyl groups, and C₆-C_10- aryl groups, especially C₁-C₆-alkyl groups, C₆-aryl groups, and C₇-C₁₀-arylalkyl groups, e.g. C₁-C₆-alkyl groups. Most especially preferred hydrocarbyl groups are methyl, ethyl, propyl, isopropyl, tert-butyl, isobutyl, C₅-C₆-cycloalkyl, cyclohexylmethyl, phenyl, and benzyl. It is to be noted that linear and branched hydrocarbyl groups cannot contain cyclic units. Aliphatic hydrocarbyl groups cannot contain aryl rings. The term “heteroatoms of Group 14-16 of the Periodic Table” includes for example Si, N, O or S. The term “C -C -ring” as used her 1 4 8 ein in connection to -R 2Si-, refers to cyclic groups containing 4 to 8 carbon atoms and a Si atom and includes for example silacycloalkanediyls, such as silacyclobutane, silacyclopentane, or 9-silafluorene. The term “halogen” includes fluoro, chloro, bromo, and iodo groups, especially chloro or fluoro groups, when relating to the complex definition. The oxidation state of the metal ion is governed primarily by the nature of the metal ion in question and the stability of the individual oxidation states of each metal ion. It is appreciated that in the complexes of the invention, the metal ion is coordinated by ligands X to satisfy the valence of the metal ion and to fill its available coordination sites. The nature of these sigma-ligands can vary greatly. The numbering of these rings will be evident from the structures indicated herein. Catalyst activity is defined in this application to be the amount of polymer produced/g catalyst/h. Catalyst metal activity is defined here to be the amount of polymer produced/g Metal/h. The term productivity is also sometimes used to indicate the catalyst activity although herein it designates the amount of polymer produced per unit weight of catalyst. The term “molecular weight” is used herein to refer to weight average molecular weight Mw unless otherwise stated. The term “consisting essentially of” is used herein to refer to that further components may be present namely those not materially affecting the essential characteristics of the compound or composition e.g. minor amounts of impurities. DETAILED DESCRIPTION OF THE DISCLOSURE

The present invention relates to a process for producing a propylene copolymer resin, comprising polymerizing propylene and at least one comonomer selected from ethylene and C4-C10 alpha olefin comonomers, preferably at least two different comonomers selected from ethylene and C4-C10 alpha olefin comonomers, more preferably, ethylene and at least one C4-C10 alpha olefin comonomer, in the presence of a polymerization catalyst comprising a specific metallocene catalyst comprising, preferably essentially consisting of, more preferably consisting of (i) a metallocene complex of formula (I) as discussed herein; (ii) a cocatalyst system comprising a cocatalyst comprising a group 13 element; and (iii) optionally a support. Details of the polymerization catalyst are discussed under section Polymerization catalyst. Polymerization in the process of the invention may be effected in one or more, e.g.1, 2, or 3, step. Preferably, the same polymerization catalyst is used in each step and ideally, it is transferred from pre-polymerization to subsequent polymerization steps in sequence in a well-known manner.

The process of the invention may utilise an in-line pre-polymerization step. The in-line pre- polymerization step takes place just before the first polymerization step (I) and may be effected in the presence of hydrogen although the concentration of hydrogen should be low if it is present. The concentration of hydrogen may be from 0 to 1 mol(hydrogen)/ kmol(propylene), preferably from 0.001 to 0.1 mol(hydrogen)/kmol(propylene). The temperature conditions within the pre-polymerization step are ideally kept low such as 0 to 50°C, preferably 5 to 40°C, more preferably 10 to 30°C. The pre-polymerization stage preferably polymerizes propylene monomer only. The residence time in the pre-polymerization reaction stage is short, typically 5 to 30 min. The pre-polymerization stage preferably generates less than 5 wt% of the total polymer formed, such as 3 wt% or less. Pre-polymerization preferably takes place in its own dedicated reactor, ideally in liquid propylene slurry. The prepolymerized catalyst is then transferred over to the first polymerization step. However, it is also possible, especially in batch processes, that pre- polymerization is carried out in the same reactor as the first polymerization step.

The present invention involves polymerizing propylene and at least one comonomer selected from ethylene and C₄-C₁₀ alpha olefin comonomers, preferably two different comonomers selected from ethylene and C₄-C₁₀ alpha olefin comonomers, more preferably ethylene and at least one C4-C10 alpha olefin comonomer. In one embodiment, propylene is polymerized with ethylene and 1-butene. The polymerization process may comprise one or more polymerization steps, provided that at least one polymerization step involves providing a propylene copolymer fraction, preferably a terpolymer fraction. Polymerization in the process of the invention may be effected in one or more, e.g.1, 2, or 3, polymerization reactors, using conventional polymerization techniques, e.g. gas phase, solution phase, slurry or bulk polymerization, or combinations thereof, like a combination of a slurry and at least one gas phase reactor. In an embodiment the process comprises the step of (I) polymerizing propylene and at least two different comonomers selected from ethylene and C4-C10 alpha olefin comonomers, preferably ethylene and at least one C4-C10 alpha olefin comonomer in a slurry reactor to produce a propylene terpolymer. In said embodiment the process is carried out in at least one slurry reactor. Where a slurry polymerization reactor is employed, this is typically effected in at least one loop reactor. Ideally, the polymerization takes place in bulk, i.e. in a medium of liquid propylene. For slurry reactors in general and in particular for bulk reactors, the reaction temperature will generally be in the range 60 to 100 ^C, preferably 70 to 85°C. The reactor pressure will generally be in the range 5 to 80 bar-g (e.g.20 to 60 bar-g), and the residence time will generally be in the range 0.1 to 5 hours (e.g.0.3 to 2 hours). It is preferred that hydrogen is used in the polymerization step. The amount of hydrogen employed is typically considerably larger than the amount used in the prepolymerization stage.

Preferably, the propylene copolymer (e.g. propylene terpolymer) resin is produced in a multistage process comprising at least two reactors connected in series. In an example, the present process is a multistage polymerization process, said process comprising an optional but preferred pre-polymerization step, followed by a first, and a second polymerization step. At least one of the polymerization steps in the multistage polymerization process may be carried out in a gas phase reactor. One preferred process configuration is based on a Borstar^® type cascade. Accordingly, in a further embodiment the process comprises (I) polymerizing in at least one slurry reactor propylene and at least one comonomer selected from ethylene and C₄-C₁₀ alpha olefin comonomers, preferably at least two different comonomers selected from ethylene and C₄-C₁₀ alpha olefin comonomers, more preferably ethylene and at least one C₄-C₁₀ alpha olefin comonomer, in a slurry reactor to produce a propylene copolymer in 50 to 99 wt% of the total weight of the propylene copolymer resin end product, and the process further comprises the step of (II) transferring the reaction mixture of step (I) into a gas phase reactor for producing propylene copolymer amounting to 1 to 50 wt% of the propylene copolymer resin end product. Preferably, the process comprises (I) polymerizing in at least one slurry reactor propylene and at least two different comonomers selected from ethylene and C4-C10 alpha olefin comonomers, more preferably ethylene and at least one C4-C10 alpha olefin comonomer, in a slurry reactor to produce a propylene terpolymer in 50 to 99 wt% of the total weight of the propylene terpolymer resin end product, and the process further comprises the step of (II) transferring the reaction mixture of step (I) into a gas phase reactor for producing propylene terpolymer amounting to 1 to 50 wt% of the propylene terpolymer resin end product. In an example a) of a multistage process the present process for the preparation of a propylene terpolymer resin, comprises: (I’) in a first polymerization step, preferably in at least one slurry reactor, polymerizing propylene and at least one comonomer selected from ethylene and C4-C10 alpha olefin comonomers, preferably ethylene, in the presence of the polymerization catalyst to produce a propylene copolymer matrix (A); and subsequently (II”) in a second polymerization step, preferably in at least on gas phase reactor, polymerizing propylene and at least one comonomer selected from ethylene and C4-C10 alpha olefin comonomers, preferably at least two different comonomers selected from ethylene and C₄-C₁₀ alpha olefin comonomers, more preferably ethylene and at least one C₄-C₁₀ alpha olefin comonomer, in the presence of the polymerization catalyst and the propylene copolymer matrix (A) from step (I) to produce a propylene copolymer (e.g. propylene terpolymer) phase (B) dispersed in the propylene copolymer matrix (A) e.g. to provide the propylene copolymer, preferably, propylene terpolymer resin. Preferably in said preferred example a) the propylene copolymer matrix (A) produced in step (I’) is produced in an amount of less than or equal to 90 wt %, and b) the propylene terpolymer phase (B) produced in step (II”) is produced in an amount of more than or equal to 10 wt %,of the total weight of the produced propylene terpolymer resin. First polymerization step (I) –propylene copolymer matrix phase production In an embodiment the present invention, the first polymerization step involves polymerizing propylene and at least one C4-C10 alpha olefin comonomer. In this embodiment, the comonomer polymerized with the propylene may be ethylene or a C4-C10 alpha olefin comonomer or a mixture of comonomers might be used such as a mixture of ethylene and a C4-C10 alpha olefin comonomer. As comonomers to propylene are preferably used ethylene, 1-butene, 1-hexene, 1-octene or any mixtures thereof, preferably ethylene. When ethylene comonomer is present in the polymer produced in the first polymerization step (I), its content may be up to 5 mol%, or 3.4 wt%, while when butene comonomer is present, then its content can be up to 5 mol%, or 6.6 wt%, provided that their combined content is at most 5 mol%, relative to the polymer as a whole. The first polymerization step may take place in any suitable reactor or series of reactors. The first polymerization step may take place in a slurry polymerization reactor such as a loop reactor or in a gas phase polymerization reactor, or a combination thereof. Where a slurry polymerization reactor is employed, this is typically effected in at least one loop reactor. Ideally, the polymerization takes place in bulk, i.e. in a medium of liquid propylene. For slurry reactors in general and in particular for bulk reactors, the reaction temperature will generally be in the range 60 to 100 ^C, preferably 70 to 85°C. The reactor pressure will generally be in the range 5 to 80 bar (e.g.20 to 60 bar), and the residence time will generally be in the range 0.1 to 5 hours (e.g.0.3 to 2 hours). When a gas phase reactor is employed, the reaction temperature will generally be in the range 60 to 120°C, preferably 70 to 90°C. The reactor pressure will generally be in the range 10 to 35 bar (e.g. 15 to 30 bar), and the residence time will generally be in the range 0.5 to 5 hours (e.g.1 to 2 hours). In a preferred embodiment, the first polymerization step takes place in a slurry loop reactor connected in cascade to a gas phase reactor. In such scenarios, the polymer produced in the loop reactor is transferred into the first gas phase reactor. It is preferred if hydrogen is used in the first polymerization step. The amount of hydrogen employed is typically considerably larger than the amount used in the prepolymerization stage. Second

The second polymerization step (II) of the process of the invention may be a gas polymerization step in which propylene and, preferably, at least two different comonomers selected from ethylene and C₄-C₁₀ alpha olefin comonomers are polymerized in the presence of the polymerization catalyst and polymer from step (I). This polymerization step takes place in at least one gas phase reactor, optionally in the presence of an inert gas such as propane. Thus, the second polymerization step may take place in a single gas phase reactor or more than one gas phase reactor connected in series or parallel. The C4-C10 alpha olefin comonomer(s) may be, for example, 1-butene, 1-hexene, 1-octene or any mixtures thereof. Preferably, step (II) involves the polymerization of propylene, ethylene and butene. In the process of the invention, the temperature in the gas phase reactor will generally be in the range of 60 to 120°C, preferably in the range of 65 and 110 ^C, more preferably in the range of 65 and 100°C, more preferably in the range of 70 to 90°C. Higher gas phase reactor temperatures will favour e.g. higher levels of productivity and, in some embodiments, comonomer (e.g. ethylene) reactivity. In the process of the invention, the reactor pressure is at least 10 bar, preferably at least 15 bar, more preferably at least 16 bar, typically in the range of 10 to 60 bar, preferably in the range of 15 to 50 bar. The residence time within any gas phase reactor will generally be 0.5 to 8 hours (e.g.0.5 to 4 hours). The gas used will be the monomer mixture optionally as mixture with a non- reactive gas such as propane. The hydrogen content within the gas phase reactor(s) is important for controlling polymer properties but is independent of the hydrogen added to prepolymerization and first polymerization steps. Hydrogen left in the reactor(s) of step I can be partially vented before a transfer to the gas phase reactor(s) of step II is effected, but it can also be transferred together with the polymer/monomer mixture of step I into the gas phase reactor(s) of step II, where more hydrogen can be added to control the molecular weight (Mw) of the copolymer, preferably terpolymer, to the desired value. The production ratio or split (by weight) between the first and second polymerization steps is ideally 55:45 to 90:10. preferably 55:45 to 87:13, preferably 60:40 to 85:15. Note that any small amount of polymer formed in prepolymerization is counted as part of the polymer prepared in the first polymerization step.

The processes of the invention employs a polymerization catalyst comprising, preferably essentially consisting of, more preferably consisting of (i) a metallocene complex of formula (I); (ii) a cocatalyst system comprising a cocatalyst comprising a group 13 element; and (iii) optionally a support. Metallocene

The metallocene catalyst complexes of the invention are asymmetrical. Asymmetrical means simply that the two ligands forming the metallocene are different, that is, each ligand bears a set of substituents that are chemically different. The metallocene complexes of the invention are preferably chiral, racemic, bridged bisindenyl C1-symmetric metallocenes in their anti-configuration. Although the complexes of the invention are formally C1-symmetric, the complexes ideally retain a pseudo-C2- symmetry since they maintain C2-symmetry in close proximity of the metal center although not at the ligand periphery. By nature of their chemistry both anti and syn enantiomer pairs (in case of C1-symmetric complexes) are formed during the synthesis of the complexes. For the purpose of this invention, racemic-anti means that the two indenyl ligands are oriented in opposite directions with respect to the cyclopentadienyl-metal-cyclopentadienyl plane, while racemic-syn means that the two indenyl ligands are oriented in the same direction with respect to the cyclopentadienyl-metal-cyclopentadienyl plane, as shown in the scheme below.

Racemic Anti Racemic Syn Formula (I), and any sub formulae, are intended to cover both syn- and anti-configurations. Preferred metallocene catalyst complexes are in the anti-configuration. The metallocene complexes of the invention are preferably employed as the racemic-anti- isomers. Ideally, therefore at least 95% mol, such as at least 98 %mol, especially at least 99 %mol of the metallocene catalyst complex is in the racemic anti-isomeric form. The present metallocene catalyst complexes require the combination of three distinctive features of the ligand framework: 1: an indenyl, preferably indacenyl, ligand with 4,8-diaryl substitution, 2: a 5-hydrocarbyloxy, preferably 5-alkoxy indenyl, preferably methoxy indene, with 6- tertiary hydrocarbyl, preferably tertiary alkyl, most preferably tert-butyl, substituent, and 3: at least one alkyl substituent larger than methyl on the 2-positions of the ligands The present invention accordingly utilizes metallocene complexes of formula (I)

wherein Mt is Zr or Hf; X is a sigma ligand; R¹ are each independently, same or different from each other, C₁-C₂₀-hydrocarbyl, optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or form together with the Si atom they are attached to a C₄-C₈-ring; R² and R²’ are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H, linear or branched C₁-C₆-alkyl, C₃-C₈-cycloalkyl, or C₆-C₉-aryl, provided that R2 and R²’ are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, C₇-C₂₀-arylalkyl, C₇-C₂₀-alkylaryl, C₆-C₂₀-aryl, or -OR³¹, with R³¹ being C₁-C₁₀- hydrocarbyl_, whereby at least one R³ per phenyl group and at least one R⁴ is not H; R⁵ and R⁶ are each independently, same or different from each other, C₁-C₁₀-hydrocarbyl, or may form together with the C atoms they are attached to a C₅-C₇-carbocycle; R⁵¹’ is C₁-C₁₀-hydrocarbyl; and R⁶’ is C(R⁶¹)3, with R⁶¹ being linear or branched C1-C6-alkyl. For the above-defined metallocene complexes of formula (I), the following represent preferable embodiments, which can be selected alone or in combination: In a complex of formula (I) it is preferred if Mt is Zr or Hf, preferably Zr. Each X is a sigma ligand. Preferably, each X is independently, same or different from each other, H, halogen, C1-C6-alkoxy, or R´ group, where R´ is C1-C6-alkyl, phenyl, or benzyl. More preferably, each X is independently, same or different from each other, Cl, benzyl, or methyl. It is preferred that both X groups are the same. Most preferably both X are Cl, methyl, or benzyl, especially Cl. Preferably R¹ are each independently, same or different from each other, C1-C10- hydrocarbyl, more preferably C1-C10-alkyl, C4-C10-cycloalkyl, C5-C10-cycloalkyl-alkyl, C7- C10-arylalkyl, C6-C10-aryl, or C7-C10-alkylaryl, such as methyl, ethyl, propyl, isopropyl, tert- butyl, isobutyl, C3-C8-cycloalkyl, cyclohexylmethyl, phenyl, or benzyl, even more preferably both are C1-C6-alkyl, C5-C6-cycloalkyl, or C6-aryl. In an embodiment each R¹ is independently, same or different from each other, C1-C10-alkyl or C1-C6-alkyl, optionally substituted with C1-C10-alkoxy. It is preferred that both R¹ groups are the same. Most preferably, both R¹ are methyl. Preferably, R¹ are each independently, same or different from each other, C1-C6 alkyl, more preferably methyl. Preferably R² and R^2’ are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H, linear C₁-C₆-alkyl, branched C₃-C₆-alkyl, or C_3-C₈ cycloalkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, tert-butyl, or cyclohexyl, provided that R² and R²’ are not both methyl, more preferably R²¹ being H, linear C₁-C₃-alkyl, or branched C₃-alkyl, provided that R² and R²’ are not both methyl . It is preferred that R^2’ is not methyl, and preferably is CH₂-R²¹, with R²¹ being linear C₁-C₆-alkyl or branched C₃-C₆- alkyl, more preferably, R²¹ being linear C₁-C₃-alkyl or branched C₃-alkyl, and R² is CH₂- R²¹, with R²¹ being H, linear C₁-C₆-alkyl, or branched C₃-C₆-alkyl, preferably R²¹ being H, linear C₁-C₆-alkyl or branched C₃-alkyl. It is further preferred that R² is methyl or ethyl. Most preferably, R² is methyl or ethyl and R^2’ is ethyl or n-propyl. Advantageously, R² and R²’ are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H or linear or branched C₁-C₆-alkyl; preferably H or linear preferably H or linear C1-C6-alkyl, more preferably H or linear C1-C4 alkyl; preferably H, methyl or ethyl, provided that R² and R²’ are not both methyl. In some embodiments, one of R² and R²’ is methyl, and the other is of the formula CH2- R²¹, with R²¹ being linear or branched C1-C6-alkyl. In such embodiments, R²¹ is preferably linear or branched C1-C4-alkyl; more preferably linear C1-C4-alkyl, even more preferably methyl or ethyl. In some embodiments, R² is methyl, and R²’ is of the formula CH2-R²¹, with R²¹ being linear or branched C1-C6-alkyl. In such embodiments, R²¹ is preferably linear or branched C1- C4-alkyl; more preferably linear C1-C4-alkyl, even more preferably methyl or ethyl. In some embodiments, neither R² nor R²’ is methyl. For example, R² and R^2’ is each independently, same or different from each other, CH2-R²¹, with R²¹ being linear or branched C1-C6-alkyl, more preferably linear or branched C1-C4-alkyl, even more preferably methyl or ethyl, yet more preferably methyl. Preferably R³ and R⁴ are each independently, same or different from each other, H, linear or branched C1-C6-alkyl, or C6-C20 aryl, more preferably H, linear or branched C1-C4-alkyl, or -OR³¹, with R³¹ being a C1-C4-hydrocarbyl. Even more preferably, each R³ and R⁴ are each independently, same or different from each other, H, methyl, ethyl, isopropyl, tert- butyl, or methoxy, especially H, methyl, or tert-butyl, whereby at least one R³ per phenyl group and at least one R⁴ is not H. Furthermore, it is possible that each of the phenyl rings have the same substitution pattern or that the three phenyl rings have different substitution patterns. It is therefore preferred if one or two R³ and/or R⁴ groups is H. If two R³ and/or R⁴ groups are H then the remaining R³ and/or R⁴ group, respectively, is preferably in the para position. If one R³ and/or R⁴ group is H then the remaining R³ and/or R⁴ groups are preferably in the meta positions. Advantageously one or two R³ per phenyl group are not H, more preferably on both phenyl groups the R³ are the same, like 3´,5´-di-methyl or 4´- tert-butyl for both phenyl groups. For the second indenyl moiety preferably one or two R⁴ on the phenyl group are not H, more preferably two R⁴ are not H, and most preferably these two R⁴ are the same like 3´,5´-di-methyl or 3´,5´-di-tert-butyl_. In one embodiment, two R³ per phenyl group are not H and on both phenyl groups the R³ are linear or branched C1-C6-alkyl, preferably methyl, and two R⁴ on the phenyl group are not H and these two R⁴ are linear or branched C1-C6 alkyl, preferably methyl. Preferably R⁵ and R⁶ form together -(R⁵⁶)m-, wherein each R⁵⁶ is independently a -CH2-, - CHR*-, or -C(R*)2- group, with R* being C1-C2-alkyl, preferably methyl, and m being 3 to 5, preferably 3 to 4; more preferably in -(R⁵⁶)m- each R⁵⁶ is -CH2-, with m being 3 to 5, preferably 3 to 4, most preferably 3. Preferably R⁵¹’ is linear or branched C1-C6-alkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, or tert-butyl, C7-C10-arylalkyl, C7-C10-alkylaryl, or C6-C10-aryl, more preferably linear C1-C6-alkyl, branched C3-C6–alkyl, or C6-aryl, even more preferably linear C1-C4-alkyl, yet even more preferably methyl or ethyl, and most preferably methyl. Preferably R⁶’ is C(R⁶¹)3, with R⁶¹ being linear C1-C3-alkyl; more preferably methyl. Thus advantageously, R⁶’ is tert-butyl.

Viewed from another aspect the invention utilizes a metallocene catalyst complex of formula (I-a)

(I-a) wherein Mt is Zr or Hf; X is a sigma ligand; n is 1 to 3, such as 1, 2 or 3, preferably 1; R¹ are each independently, same or different from each other, C1-C20-hydrocarbyl, optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or form together with the Si atom they are attached to a C4-C8-ring; R² and R²’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H, linear or branched C 2 1-C6-alkyl, C3-C8-cycloalkyl, or C6-C9-aryl, provided that R and R²’ are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C1-C6-alkyl, C7-C20-arylalkyl, C7-C20-alkylaryl, C6-C20-aryl, or -OR³¹, with R³¹ being C1-C10- hydrocarbyl, whereby at least one R³ per phenyl group and at least one R⁴ is not H; R⁵¹’ is C1-C10-hydrocarbyl; and R⁶’ is C(R⁶¹)3, with R⁶¹ being linear or branched C1-C6-alkyl. For the above-defined metallocene complexes of formula (I-a), the following represent preferable embodiments, which can be selected alone or in combination: In a complex of formula (I-a) it is preferred if Mt is Zr or Hf, preferably Zr. Each X is a sigma ligand. Preferably, each X is independently, same or different from each other, H, halogen, C₁-C₆-alkoxy, or R´ group, where R´ is C_1-C₆-alkyl, phenyl, or benzyl. More preferably, each X is independently, same or different from each other, Cl, benzyl, or methyl. It is preferred that both X groups are the same. Most preferably both X are Cl, methyl, or benzyl, especially Cl. Preferably R¹ are each independently, same or different from each other, C_1-C₁₀- hydrocarbyl, more preferably C₁-C_10-alkyl, C₄-C_10-cycloalkyl, C₅-C_10-cycloalkyl-alkyl, C₇- C₁₀-arylalkyl, C_6-C₁₀-aryl, or C₇-C_10-alkylaryl, such as methyl, ethyl, propyl, isopropyl, tert- butyl, isobutyl, C₃-C₈-cycloalkyl, cyclohexylmethyl, phenyl, or benzyl, even more preferably both are C_1-C₆-alkyl, C₅-C_6-cycloalkyl, or C₆-aryl. In an embodiment each R¹ is independently, same or different from each other, C₁-C₁₀-alkyl, optionally substituted with C₁-C₁₀-alkoxy. It is preferred that both R¹ groups are the same. Most preferably, both R¹ are methyl. Preferably, R¹ are each independently, same or different from each other, C₁-C₆ alkyl, more preferably methyl. Preferably R² and R^2’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H, linear C1-C6-alkyl, branched C3-C6-alkyl, or C3-C8 cycloalkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, tert-butyl, or cyclohexyl, provided that R² and R²’ are not both methyl l, more preferably R²¹ being H, linear C1-C3-alkyl, or branched C3-alkyl, provided that R² and R²’ are not both methyl. It is preferred that R^2’ is not methyl, and preferably is CH2-R²¹, with R²¹ being linear C1-C6-alkyl or branched C3-C6- alkyl, more preferably, R²¹ being linear C1-C3-alkyl or branched C3-alkyl, and R² is CH2- R²¹, with R²¹ being H, linear C1-C6-alkyl, or branched C3-C6-alkyl, preferably R²¹ being H, linear C1-C3-alkyl, or branched C3-alkyl. It is further preferred that R² is methyl or ethyl. Most preferably, R² is methyl or ethyl and R^2’ is ethyl or n-propyl. Advantageously, R² and R²’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H or linear or branched C1-C6-alkyl; preferably H or linear preferably H or linear C1-C6-alkyl, more preferably H or linear C1-C4 alkyl; preferably H, methyl or ethyl, provided that R² and R²’ are not both methyl. In some embodiments, one of R² and R²’ is methyl, and the other is of the formula CH2- R²¹, with R²¹ being linear or branched C1-C6-alkyl. In such embodiments, R²¹ is preferably linear or branched C₁-C₄-alkyl; more preferably linear C₁-C₄-alkyl, even more preferably methyl or ethyl. In some embodiments, R² is methyl, and R²’ is of the formula CH2-R²¹, with R²¹ being linear or branched C₁-C₆-alkyl. In such embodiments, R²¹ is preferably linear or branched C₁- C₄-alkyl; more preferably linear C₁-C₄-alkyl, even more preferably methyl or ethyl. In some embodiments, neither R² nor R²’ is methyl. For example, R² and R^2’ is each independently, same or different from each other, CH₂-R²¹, with R²¹ being linear or branched C₁-C₆-alkyl, more preferably linear or branched C₁-C₄-alkyl, even more preferably methyl or ethyl, yet more preferably methyl. Preferably R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, or C₆-C₂₀ aryl, more preferably H, linear or branched C₁-C₄-alkyl, or -OR³¹, with R³¹ being a C₁-C₄-hydrocarbyl. Even more preferably, each R³ and R⁴ are each independently, same or different from each other, H, methyl, ethyl, isopropyl, tert- butyl, or methoxy, especially H, methyl, or tert-butyl, whereby at least one R³ per phenyl group and at least one R⁴ is not H. Furthermore, it is possible that each of the phenyl rings have the same substitution pattern or that the three phenyl rings have different substitution patterns. It is therefore preferred if one or two R³ and/or R⁴ groups is H. If two R³ and/or R⁴ groups are H then the remaining R³ and/or R⁴ group, respectively, is preferably in the para position. If one R³ and/or R⁴ group is H then the remaining R³ and/or R⁴ groups are preferably in the meta positions. Advantageously one or two R³ per phenyl group are not H, more preferably on both phenyl groups the R³ are the same, like 3´,5´-di-methyl or 4´- tert-butyl for both phenyl groups. For the indenyl moiety preferably one or two R⁴ on the phenyl group are not H, more preferably two R⁴ are not H, and most preferably these two R⁴ are the same like 3´,5´-di- methyl or 3´,5´-di-tert-butyl. In one embodiment, two R³ per phenyl group are not H and on both phenyl groups the R³ are linear or branched C1-C6-alkyl, preferably methyl, and two R⁴ on the phenyl group are not H and these two R⁴ are linear or branched C1-C6 alkyl, preferably methyl. Preferably R⁵¹’ is linear or branched C1-C6-alkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, or tert-butyl, C7-C10-arylalkyl, C7-C10-alkylaryl, or C6-C10-aryl, more preferably linear C₁-C₆-alkyl, branched C₃-C₆–alkyl, or C₆-aryl, even more preferably linear C₁-C₄-alkyl, yet even more preferably methyl or ethyl, and most preferably methyl. Preferably R⁶’ is C(R⁶¹)₃, with R⁶¹ being linear C₁-C₃-alkyl; more preferably methyl. Thus advantageously, R⁶’ is tert-butyl. Viewed from another aspect the invention utilizes a metallocene catalyst complex of formula (I-b)

wherein Mt is Zr or Hf; X is a sigma ligand; R¹ are each independently, same or different from each other, C₁-C₂₀-hydrocarbyl, optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or form together with the Si atom they are attached to a C₄-C₈-ring; R² and R²’ are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H or linear or branched C₁-C₆-alkyl, provided that R² and R²’ are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, C₇-C₂₀-arylalkyl, C₇-C₂₀-alkylaryl, C₆-C₂₀-aryl, or –OR³¹, with R³¹ being C₁-C₁₀- hydrocarby, whereby at least one R³ per phenyl group and at least one R⁴ is not H. For the above-defined metallocene complexes of formula (I-b), the following represent preferable embodiments, which can be selected alone or in combination: In a complex of formula (I-b) it is preferred if Mt is Zr or Hf, preferably Zr. Each X is a sigma ligand. Preferably, each X is independently, same or different from each other, H, halogen, C₁-C₆-alkoxy, or R´ group, where R´ is C_1-C₆-alkyl, phenyl, or benzyl. More preferably, each X is independently, same or different from each other, Cl, benzyl, or methyl. It is preferred that both X groups are the same. Most preferably both X are Cl, methyl, or benzyl, especially Cl. Preferably R¹ are each independently, same or different from each other, C_1-C₁₀- hydrocarbyl, more preferably C₁-C_10-alkyl, C₄-C_10-cycloalkyl, C₅-C_10-cycloalkyl-alkyl, C₇- C₁₀-arylalkyl, C_6-C₁₀-aryl, or C₇-C_10-alkylaryl, such as methyl, ethyl, propyl, isopropyl, tert- butyl, isobutyl, C₃-C₈-cycloalkyl, cyclohexylmethyl, phenyl, or benzyl, even more preferably both are C_1-C₆-alkyl, C₅-C_6-cycloalkyl, or C₆-aryl. In an embodiment each R¹ is independently, same or different from each other, C₁-C₁₀-alkyl, optionally substituted with C₁-C₁₀-alkoxy. It is preferred that both R¹ groups are the same. Most preferably, both R¹ are methyl. Preferably, R¹ are each independently, same or different from each other, C₁-C₆ alkyl, more preferably methyl. Preferably R² and R^2’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H, linear C1-C3-alkyl or branched C3-alkyl, such as methyl, ethyl, n-propyl, i- propyl, provided that R² and R²’ are not both methyl. It is preferred that R^2’ is not methyl, and preferably is CH2-R²¹, with R²¹ being linear C1-C3-alkyl or branched C3-alkyl, and R² is CH2-R²¹, with R²¹ being H, linear C1-C3-alkyl or branched C3-alkyl. It is further preferred that R² is methyl or ethyl. Most preferably, R² is methyl or ethyl and R^2’ is ethyl or n-propyl. Advantageously, R² and R²’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H or linear or branched C1-C6-alkyl; preferably H or linear preferably H or linear C1-C6-alkyl, more preferably H or linear C1-C4 alkyl; preferably H, methyl or ethyl, provided that R² and R²’ are not both methyl. In some embodiments, one of R² and R²’ is methyl, and the other is of the formula CH2- R²¹, with R²¹ being linear or branched C1-C6-alkyl. In such embodiments, R²¹ is preferably linear or branched C1-C4-alkyl; more preferably linear C1-C4-alkyl, even more preferably methyl or ethyl. In some embodiments, R² is methyl, and R²’ is of the formula CH2-R²¹, with R²¹ being linear or branched C1-C6-alkyl. In such embodiments, R²¹ is preferably linear or branched C1- C₄-alkyl; more preferably linear C₁-C₄-alkyl, even more preferably methyl or ethyl. In some embodiments, neither R² nor R²’ is methyl. For example, R² and R^2’ is each independently, same or different from each other, CH₂-R²¹, with R²¹ being linear or branched C₁-C₆-alkyl, more preferably linear or branched C₁-C₄-alkyl, even more preferably methyl or ethyl, yet more preferably methyl. Preferably R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, or C₆-C₂₀ aryl, more preferably H, linear or branched C₁-C₄-alkyl, or -OR³¹, with R³¹ being C₁-C₄-hydrocarbyl. Even more preferably, each R³ and R⁴ are each independently, same or different from each other, H, methyl, ethyl, isopropyl, tert- butyl, or methoxy, especially H, methyl, or tert-butyl, whereby at least one R³ per phenyl group and at least one R⁴ is not H. Furthermore, it is possible that each of the phenyl rings have the same substitution pattern or that the three phenyl rings have different substitution patterns. It is therefore preferred if one or two R³ and/or R⁴ groups is H. If two R³ and/or R⁴ groups are H then the remaining R³ and/or R⁴ group, respectively, is preferably in the para position. If one R³ and/or R⁴ group is H then the remaining R³ and/or R⁴ groups are preferably in the meta positions. Advantageously one or two R³ per phenyl group are not H, more preferably on both phenyl groups the R³ are the same, like 3´,5´-di-methyl or 4´- tert-butyl for both phenyl groups. For the indenyl moiety preferably one or two R⁴ on the phenyl group are not H, more preferably two R⁴ are not H, and most preferably these two R⁴ are the same like 3´,5´-di- methyl or 3´,5´-di-tert-butyl. In one embodiment, two R³ per phenyl group are not H and on both phenyl groups the R³ are linear or branched C1-C6-alkyl, preferably methyl, and two R⁴ on the phenyl group are not H and these two R⁴ are linear or branched C1-C6 alkyl, preferably methyl. Preferred metallocene catalysts complexes are MC-I1, MC-I2 and MC-I3 as described in the examples below. Cocatalyst To form active catalytic species it is normally necessary to employ a cocatalyst as is well known in the art. Cocatalysts comprising one or more compounds of Group 13 metals, like organoaluminium, organoboron, and/or borate compounds used to activate metallocene catalysts are suitable for use in this invention. In some examples, organoboron and/or borate compounds are not used. According to the present invention a cocatalyst system comprising an aluminoxane cocatalyst and optionally a boron containing cocatalyst is advantageously used in combination with the above defined metallocene catalyst complex. Preferably only cocatalysts comprising aluminium, like organoaluminium compounds used to activate metallocene catalysts, are utilized in this invention. In a preferred aspect of the present invention a cocatalyst system essentially consisting of, preferably consisting of, an aluminoxane cocatalyst is advantageously used in combination with the above defined metallocene catalyst complex. Thus, preferably no further cocatalysts comprising one or more compounds of Group 13 metals other than aluminium, like organoboron and/or borate compounds, used to activate metallocene catalysts are comprised in the polymerization catalyst. Suitable amounts of cocatalyst will be well known to the person skilled in the art. Preferably, the amount of cocatalyst is chosen to reach below defined molar ratios. The molar ratio of Al from the aluminoxane to the metal ion (Mt) (preferably zirconium) of the metallocene Al/Mt may be in the range 10:1 to 2000:1 mol/mol, preferably 50:1 to 1000:1, and more preferably 100:1 to 600:1 mol/mol. When a boron cocatalyst is used, the molar ratio of boron (B) to the metal ion (Mt) (preferably zirconium) of the metallocene B/Mt may be in the range 0.1:1 to 10:1 mol/mol, preferably 0.3:1 to 7:1, especially 0.5:1 to 3:1 mol/mol. Even more preferably, the molar ratio of feed amounts of boron (B) to metal ion (Mt), preferably zirconium, of the metallocene B/Mt is from 0.5:1 to 2:1 Aluminoxane cocatalyst The aluminoxane cocatalyst can be one of formula (A):

where n is usually from 6 to 20 and R has the meaning below. Aluminoxanes are formed on partial hydrolysis of organoaluminum compounds, for example those of the formula AlR₃, AlR₂Y and Al₂R₃Y₃ where R can be, for example, C₁- C₁₀-alkyl, preferably C₁-C₅-alkyl, or C₃-C₁₀-cycloalkyl, C₇-C₁₂-arylalkyl or -alkylaryl and/or phenyl or naphthyl, and where Y can be hydrogen, halogen, preferably chlorine or bromine, or C₁-C₁₀-alkoxy, preferably methoxy or ethoxy. The resulting oxygen-containing aluminoxanes are not in general pure compounds but mixtures of oligomers of the formula (A). The preferred aluminoxane is methylaluminoxane (MAO). Since the aluminoxanes used according to the invention as cocatalysts are not, owing to their mode of preparation, pure compounds, the molarity of aluminoxane solutions hereinafter is based on their aluminium content. Boron containing cocatalyst According to the present invention, the aluminoxane cocatalyst can be used in combination with a boron containing cocatalyst. It will be appreciated by the person skilled in the art that where boron based cocatalysts are employed, it is normal to pre-alkylate the complex by reaction thereof with an aluminium alkyl compound, such as TIBA. This procedure is well known and any suitable aluminium alkyl, e.g. Al(C1-C6 alkyl)3 can be used. Preferred aluminium alkyl compounds are triethylaluminium, tri-isobutylaluminium, tri-isohexylaluminium, tri-n-octylaluminium and tri-isooctylaluminium. Alternatively, when a borate cocatalyst is used, the metallocene complex is in its alkylated version, that is for example a dimethyl or dibenzyl metallocene complex can be used. Boron containing cocatalysts of interest include those of formula (B) BY3 (B) wherein Y is the same or different and is hydrogen, C1-C10-haloalkyl, or C6-C20-haloaryl, or fluorine, chlorine, bromine or iodine. Preferred examples for Y are fluorine, trifluoromethyl, unsaturated groups such as haloaryl like p-fluorophenyl, 3,5-difluorophenyl, pentachlorophenyl, pentafluorophenyl, 3,4,5-trifluorophenyl and 3,5-di(trifluoromethyl)phenyl. Most preferably, Y are fluorine, trifluoromethyl, aromatic fluorinated groups such as p- fluorophenyl, 3,5-difluorophenyl, pentafluorophenyl, 3,4,5-trifluorophenyl and 3,5- di(trifluoromethyl)phenyl. Preferred boron containing cocatalysts of formula (B) are trifluoroborane, tris(4- fluorophenyl)borane, tris(3,5-difluorophenyl)borane, tris(2,4,6-trifluorophenyl)borane, tris(penta-fluorophenyl)borane, and/or tris(3,4,5-trifluorophenyl)borane. Particular preference is given to tris(pentafluorophenyl)borane. However it is preferred that borates are used, i.e. compounds containing a borate anion. These compounds have formula (C): Z₄B^–-W⁺ (C) wherein Z is a substituted phenyl derivative, said substituent being halo-C_1-C₆-alkyl or halogen; and W⁺ is a cationic counterion. Preferably the substituents of Z are are fluoro or trifluoromethyl. Most preferably, the phenyl group is perfluorinated. The borate anion Z₄B^– is preferably a weakly-coordinating anion such as tetrakis(pentafluorophenyl)borate. Suitable cationic counterions W⁺ are triarylcarbenium such as triphenylcarbenium or protonated amine or aniline derivatives such as methylammonium, anilinium, dimethylammonium, diethylammonium, N- methylanilinium, diphenylammonium, N,N-dimethylanilinium, trimethylammonium, triethylammonium, tri-n- butylammonium, methyldiphenylammonium, pyridinium, p-bromo-N,N- dimethylanilinium or p-nitro-N,N-dimethylanilinium. Preferred ionic compounds which can be used according to the present invention include: tributylammoniumtetra(pentafluorophenyl)borate, tributylammoniumtetra(trifluoromethylphenyl)borate, tributylammoniumtetra(4-fluorophenyl)borate, N,N-dimethylcyclohexylammoniumtetrakis(pentafluorophenyl)borate, N,N-dimethylbenzylammoniumtetrakis(pentafluorophenyl)borate, N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, N,N-di(propyl)ammoniumtetrakis(pentafluorophenyl)borate, di(cyclohexyl)ammoniumtetrakist(pentafluorophenyl)borate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, or ferroceniumtetrakis(pentafluorophenyl)borate. Preference is given to triphenylcarbeniumtetrakis(pentafluorophenyl) borate, N,N- dimethylcyclohexylammoniumtetrakis(pentafluorophenyl)borate or N,N- dimethylbenzylammoniumtetrakis(pentafluorophenyl)borate. Mostly preferred are triphenylcarbeniumtetrakis(pentafluorophenyl) borate, N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, N,N- dimethylcyclohexylammoniumtetrakis(pentafluorophenyl)borate, or N,N- dimethylbenzylammoniumtetrakis(pentafluorophenyl)borate. Catalyst Manufacture The metallocene catalysts can be used in supported or unsupported form. The particulate support material used is preferably an organic or inorganic material, such as silica, alumina or zirconia or a mixed oxide such as silica-alumina, in particular silica, alumina or silica- alumina. The use of a silica support is preferred. The skilled person is aware of the procedures required to support a metallocene catalyst. Especially preferably the support is a porous material so that the complex may be loaded into the pores of the support, e.g. using a process analogous to those described in WO94/14856, WO95/12622 and WO2006/097497. The particle size is not critical but is preferably in the range 5 to 200 μm, more preferably 20 to 80 μm. The use of these supports is routine in the art. Especially preferred procedures for producing such supported catalysts are those described in WO2020/239598, and WO2020/239603. In another embodiment, no external carrier is used but the catalyst is still presented in solid particulate form. Thus, no external support material, such as inert organic or inorganic carrier, for example silica as described above is employed. Such catalysts can be prepared as described for example in WO2003/051934, WO2014/060540, and WO2019/179959 The particulate support material used is an inorganic porous support such as a silica, alumina or a mixed oxide such as silica-alumina, in particular silica. The use of a silica support is preferred. The complex may be loaded into the pores of the particulate support, e.g. using a process analogous to those described in W094/14856, W095/12622, W02006/097497, and EP18282666. The average particle size of the support such as silica support can be typically from 10 to 100 µm. However, it has turned out that special advantages can be obtained, if the support has an average particle size from 15 to 80 µm, preferably from 18 to 50 µm. The average pore size of the inorganic porous support such as silica support can be in the range from 10 to 100 nm and the pore volume from 1 to 3 mL/g. The pore diameter of the inorganic porous support such as silica support can be in the range from 20 to 40 nm. The surface area of the inorganic porous support such as silica support can be typically in the range from 100 to 400 m²/g. Examples of suitable support materials are, for instance, ES757 produced and marketed by PQ Corporation, Sylopol 948 produced and marketed by Grace or SUNSPERA DM-L- 303 silica produced by AGC Si-Tech Co. Supports can be optionally calcined prior to the use in catalyst preparation in order to reach optimal silanol group content. The use of these supports is routine in the art. The catalyst can contain from 5 to 500 µmol, such as 10 to 100 µmol of transition metal of the metallocene per gram of support such as silica, and 3 to 15 mmol of Al per gram of support such as silica. The present polymerization catalyst may be produced by e.g. as described in WO2020/239603 or WO2020/239598. A polymerization catalyst containing such metallocenes may be produced by a process including the steps of P1-a) combining the porous inorganic support with a first portion of the aluminoxane cocatalyst in a hydrocarbon solvent to obtain aluminoxane cocatalyst treated support, optionally followed by thermal treatment of the aluminoxane treated support; P1-b) dissolving the metallocene complex in a hydrocarbon solvent, preferably an aromatic solvent, more preferably toluene, optionally adding a second portion of the aluminoxane cocatalyst in the hydrocarbon solvent optionally the boron containing cocatalyst wherein the amount of the first portion of the aluminoxane cocatalyst added in step a) is 75.0 to 100.0 wt% of the total amount of aluminoxane cocatalyst and the amount the second portion of the aluminoxane cocatalyst added in step b) is 0.0 to 25.0 wt% of the total amount of aluminoxane cocatalyst and the boron containing cocatalyst, when present, is added in an amount that a boron/M molar ratio of feed amounts in the range of 0.1 :1 to 10:1 is reached;; P1-c) adding the solution obtained in step b) to the aluminoxane cocatalyst treated support obtained in step a) and optionally P1-d) drying the so obtained supported catalyst system. In step P1-b) of the process, the components can be mixed in any order. The optional boron containing cocatalyst can be mixed with the metallocene complex dissolved in the hydrocarbon solvent and followed by addition the optional aluminoxane, or the metallocene complex dissolved in the hydrocarbon solvent can be mixed with the optional aluminoxane and a hydrocarbon followed by addition of boron containing cocatalyst and so on. In some embodiments, all components might be combined simultaneously. Only one impregnation step is used, i.e. the treated support of step a) is loaded only in one step with the metallocene. In a preferred aspect of the present invention the process comprises P2-a) combining the porous inorganic support with aluminoxane cocatalyst in a hydrocarbon solvent to obtain aluminoxane cocatalyst treated support, optionally followed by thermal treatment of the aluminoxane treated support, filtering off the hydrocarbon solvent, optionally washing with an aromatic solvent, repeating the filtration and washing steps to remove unreacted aluminium compounds; drying the final aluminoxane cocatalyst treated support; P2-b) dissolving the metallocene in a hydrocarbon solvent optionally adding a methylaluminoxane cocatalyst in a hydrocarbon solvent, wherein the amount of methylaluminoxane cocatalyst added in step a) is 75.0 to 100.0 wt% of the total amount of methylaluminoxane cocatalyst and the amount of aluminoxane cocatalyst added in step b) is 0.0 to 25.0 wt% of the total amount of methylaluminoxane cocatalyst, to obtain a metallocene solution optionally comprising aluminoxane cocatalyst; P2-c) adding the metallocene solution to the aluminoxane cocatalyst treated support obtained in step a) and optionally P2-d) drying the so obtained supported catalyst system. If desired, the obtained supported catalyst system may be provided as an oil slurry with a desired solid content. The solid catalyst content in the slurry may be e.g. up to 30 wt%, like up to 25 wt%. The amounts of support, aluminoxane, preferably MAO, boron containing cocatalyst and metallocene depend on the desired herein defined ratios (boron/M, Al/M, Al/SiO2, M/SiO2). It is a feature of the invention that the claimed process enables the formation of polypropylene with very high melting point. These features can be achieved at commercially interesting polymerization temperatures, e.g.60 °C or more, such as from 60 °C to 90 °C. The polydispersity index (Mw/Mn) of the polymers depend on the polymerization conditions in each reactor, and can be between 2.0 and 7.0. In a particular embodiment, the propylene polymers obtained using the catalysts of the invention have a narrow polydispersity index (Mw/Mn), between 2.0 and 4.0.

Propylene copolymers with ethylene or with C₄-C₁₀ alpha olefin comonomers, preferably propylene terpolymers with ethylene and with C₄-C₁₀ alpha olefin comonomers, more preferably propylene-ethylene-butene terpolymers, made by the process of the invention can be made with high productivity. The productivity of the polymerization process may be at least 13 kg of polymer per gram of catalyst, preferably at least 14 kg of polymer per gram of catalyst, more preferably at least 14.5 kg polymer per gram of catalyst. The polymerization temperature may be above 60°C, preferably above 65°C. The process of the invention may be used to produce propylene copolymers, preferably propylene terpolymers, having relatively low MFR2. For example, the MFR2 may below 15, preferably below 10 and, for example, below 8. When such copolymers are produced in liquid monomers, the MFR2 may be below 10, preferably below 8. The propylene copolymers may have a total comonomer content of 0.5 to 10 weight %, preferably 1 to 8 weight %, for example, 2 to 7 weight %. For example, the propylene copolymer may be a terpolymer having an ethylene content of 0.5 to 2 weight %, and a C4-C10 alpha olefin comonomer content of 4 to 8 weight %. The propylene copolymer may be a terpolymer having an ethylene content of 0.8 to 1.8 weight %, and a C4-C10 alpha olefin comonomer content of 4.5 to 7 weight %. The propylene copolymer may be a terpolymer having an ethylene content of 0.9 to 1.5 weight %, and a C4-C10 alpha olefin comonomer content of 4.8 to 6.5 weight %. The propylene copolymer may be a terpolymer having an ethylene content of 1.0 to 1.3 weight %, and a C4-C10 alpha olefin comonomer content of 5.0 to 6.0 weight %. In one embodiment, the propylene copolymer may be a terpolymer having an ethylene content of 0.8 to 1.8 weight %, and a C4 alpha olefin comonomer content of 4.5 to 7 weight %. The propylene copolymer may be a terpolymer having an ethylene content of 0.9 to 1.5 weight %, and a C4 alpha olefin comonomer content of 4.8 to 6.5 weight %. The propylene copolymer may be a terpolymer having an ethylene content of 1.0 to 1.3 weight %, and a C4 alpha olefin comonomer content of 5.0 to 6.0 weight %. In some examples, the propylene copolymer is a terpolymer having an ethylene content and C₄-C₁₀ alpha olefin comonomer (e.g. C₄ alpha olefin comonomer) content as described above in combination with an MFR₂ may below 15, preferably below 10 and, for example, below 8. An advantage of certain embodiments of the present disclosure is that propylene copolymers having such MFR₂ properties may be produced at desirable levels of productivity. Preferably, such propylene copolymers may be produced at relatively high levels of productivity, for example, of at least 13 kg of polymer per gram of catalyst, preferably at least 14 kg of polymer per gram of catalyst, more preferably at least 14.5 kg polymer per gram of catalyst. The polymers made by the catalysts of the description are useful in all kinds of end articles such as pipes, films (cast, blown or BOPP films, such as for example BOPP for capacitor film), fibers (such as spun-bond and melt-blown fibers), moulded articles (e.g. injection moulded, blow moulded, rotomoulded articles), extrusion coatings and so on. The invention will now be illustrated by reference to the following non-limiting Examples. EXPERIMENTAL Measurement methods Al, B and Zr determination (ICP-method) In a glovebox, an aliquot of the catalyst (ca.40 mg) was weighed into glass weighting boat using analytical balance. The sample was then allowed to be exposed to air overnight while being placed in a steel secondary container equipped with an air intake. Then 5 mL of concentrated (65 %) nitric acid was used to rinse the content of the boat into the Xpress microwave oven vessel (20 mL). A sample was then subjected to a microwave-assisted digestion using MARS 6 laboratory microwave unit over 35 minutes at 150 °C. The digested sample was allowed to cool down for at least 4 h and then was transferred into a glass volumetric glass flask of 100 mL volume. Standard solutions containing 1000 mg/L Y and Rh (0.4 mL) were added. The flask was then filled up with distilled water and shaken well. The solution was filtered through 0.45 µm Nylon syringe filters and then subjected to analysis using Thermo iCAP 6300 ICP-OES and iTEVA software. The instrument was calibrated for Al, B, Hf, Mg, Ti and Zr using a blank (a solution of 5 % HNO3) and six standards of 0.005 mg/L, 0.01 mg/L, 0.1 mg/L, 1 mg/L, 10 mg/L and 100 mg/L of Al, B, Hf, Mg, Ti and Zr in solutions of 5 % HNO3 distilled water. However, not every calibration point was used for each wavelength. Each calibration solution contained 4 mg/L of Y and Rh standards. Al 394.401 nm was calibrated using the following calibration points: blank, 0.1 mg/L, 1 mg/L, 10 mg/L and 100 mg/L. Al 167.079 nm was calibrated as Al 394.401 nm excluding 100 mg/L and Zr 339.198 nm using the standards of blank, 0.01 mg/L, 0.1 mg/L, 1 mg/L, 10 mg/L and 100 mg/L. Curvilinear fitting and 1/concentration weighting was used for the calibration curves. Immediately before analysis the calibration was verified and adjusted (instrument reslope function) using the blank and a 10 mg/L Al, B, Hf, Mg, Ti and Zr standard which had 4 mg/L Y and Rh. A quality control sample (QC: 1 mg/L Al, Au, Be, Hg & Se; 2 mg/L Hf & Zr, 2.5 mg/L As, B, Cd, Co, Cr, Mo, Ni, P, Sb, Sn & V; 4 mg/L Rh & Y; 5 mg/L Ca, K, Mg, Mn, Na & Ti; 10 mg/L Cu, Pb and Zn; 25 mg/L Fe and 37.5 mg/L Ca in a solution of 5 % HNO3 in distilled water) was run to confirm the reslope for Al, B, Hf, Mg, Ti and Zr. The QC sample was also run at the end of a scheduled analysis set. The content for Zr was monitored using Zr 339.198 nm {99} line. The content of aluminium was monitored via the 167.079 nm {502} line, when Al concentration in test portion was under 2 wt % and via the 394.401 nm {85} line for Al concentrations above 2 wt%. Y 371.030 nm {91} was used as internal standard for Zr 339.198 nm and Al 394.401 nm and Y 224.306 nm {450} for Al 167.079 nm. The content for B was monitored using B 249 nm line. The reported values were back calculated to the original catalyst sample using the original mass of the catalyst aliquot and the dilution volume. Catalyst Activity The catalyst activity was calculated on the basis of the following formula: amount of polymer produced (kg) Catalyst Activity (kg-PP/g-Cat/h) = catalyst loading (g) × polymerization time (h) The catalyst productivity was calculated on the basis of the following formula: amount of polymer produced (kg) Catalyst productivity (kg-PP/g-Cat) = catalyst loading (g) Polymer powder bulk density Instruments: Electronic balance: Range from 0,1g-11000g Graduated glass cylinder: Volume = max.250ml Plastic spoon: Volume=125ml Plastic funnel: D=105mm Execution: A glass cylinder was filled up to a volume of 250 ml by pouring in the unstabilised polymer powder, using a plastic spoon and a plastic funnel. Calculation: Mass of polymer (g)/measured volume (ml) XS The xylene soluble fraction (XS) as defined and described in the present invention was determined in line with ISO 16152 as follows: 2.5±0.1 g of the polymer were dissolved in 250 ml o-xylene under reflux conditions and continuous stirring, under nitrogen atmosphere. After 30 minutes, the solution was allowed to cool, first for 15 minutes at ambient temperature and then maintained for 4 hours under controlled conditions at 25 ± 0.5 °C. The solution was filtered through filter paper. For determination of the xylene soluble content, an aliquot (100 ml) of the filtrate was taken. This aliquot was evaporated in nitrogen flow and the residue dried under vacuum at 100 °C until constant weight is reached. The xylene soluble fraction (weight percent) can then be determined as follows: XS% = (100 x m¹ x v⁰)/(m⁰ x v¹), wherein m⁰ designates the initial polymer amount (grams), m¹ defines the weight of residue (grams), v⁰ defines the initial volume (milliliter) and v¹ defines the volume of the analyzed sample (milliliter). To obtain the amorphous copolymer fraction for further characterization with GPC and NMR, the remaining xylene soluble filtrate was precipitated with acetone. The precipitated polymer was filtered and dried in the vacuum oven at 100 °C to constant weight. GPC: Molecular weight averages, molecular weight distribution, and polydispersity index (Mn, Mw, Mw/Mn) The MWD and the corresponded molecular weight averages Mn, Mw, Mv and Mz of the polymer sample were determined by using Gel Permeation Chromatography (GPC) at 160°C. All samples were integrated at the low M_w end up to the 3^rd last calibration point of the calibration curve (PS = 1820 g/mol ~ 1340 g/mol PP equivalent). A high temperature GPC equipped with a suitable concentration detector (like IR5 or IR4 from PolymerChar (Valencia, Spain), an online four capillary bridge viscometer (PL-BV 400-HT), and a dual light scattering detector (PL-LS 15/90 light scattering detector) with a 15° and 90° angle was used. 3x Olexis and 1x Olexis Guard columns from Agilent as stationary phase and 1,2,4-trichlorobenzene (TCB, stabilized with 250 mg/L 2,6-Di tert butyl-4-methyl-phenol) as mobile phase at 160 °C and at a constant flow rate of 1 mL/min was applied. 200 μL of sample solution were injected per analysis. All samples were prepared by dissolving 8.0 – 10.0 mg of polymer in 10 mL (at 160 °C) of stabilized TCB (same as mobile phase) for 2,5 hours at 160°C under continuous gentle shaking. The injected concentration of the polymer solution at 160 °C (c_160°C) was determined in the following way. 0,8772

With: w₂₅ (polymer weight) and V₂₅ (Volume of TCB at 25°C). The column set was calibrated using universal calibration (according to ISO 16014-2:2019) with 19 narrow MWD polystyrene (PS) standards in the range of 0.5 kg/mol to 11500 kg/mol. The PS standards were dissolved at 160°C for 15 min or alternatively at room temperatures at a concentration of 0.2 mg/ml for molecular weight higher and equal 899 kg/mol and at a concentration of 1 mg/ml for molecular weight below 899 kg/mol. The conversion of the polystyrene peak molecular weight to polypropylene molecular weights is accomplished by using the Mark Houwink equation and the following Mark Houwink constants: K_PS = 19 x 10^-5 ml/g, α_PS = 0.655 K_PP = 39 x 10^-5 ml/g, α_PP = 0.725 A third order polynomial fit was used to fit the calibration data. All samples were prepared in the concentration range of 0.5 -1 mg/ml and dissolved at 160 °C for 3 hours under continuous gentle shaking Molecular weight averages (M_n, M_w, M_v and M_z), Molecular weight distribution (MWD) and its broadness, described by the polydispersity index PD= M_w/M_n (wherein M_n is the number average molecular weight and M_w is the weight average molecular weight) were determined using the following formulas:

DSC The DSC curves and data were produced on a DSC Q200 TA Instrument, by placing a 5- 7 mg sample cut from the polymer MFR string, into a closed DSC aluminum pan, heating the sample from -10 °C to 225 °C at 10 °C/min, holding for 10 min at 225 °C, cooling from 225 °C to –30 °C, holding for 5 min at –30 °C, heating from –30 °C to 225 °C at 10 °C/min. The reported T_m values are those of the peak of the endothermic heat flow determined from the second heating scan. The SIT was calculated from the DSC curve as described in US2021309774. Melt Flow Rate The melt flow rate (MFR) was determined according to ISO 1133 and is indicated in g/10 min. The MFR is an indication of the flowability, and hence the processability, of the polymer. The higher the melt flow rate, the lower the molecular weight of the polymer. The MFR is determined at 230°C and may be determined at different loadings such as 2.16 kg (MFR2) or 21.6 kg (MFR21). NMR Quantitative nuclear-magnetic resonance (NMR) spectroscopy was used to quantify the comonomer content of the polymers. Quantitative ¹³C{¹H} NMR spectra recorded in the molten-state using a Bruker Avance III 500 NMR spectrometer operating at 500.13 and 125.76 MHz for ¹H and ¹³C respectively. All spectra were recorded using a ¹³C optimised 7 mm magic-angle spinning (MAS) probe head at 180°C using nitrogen gas for all pneumatics. Approximately 200 mg of material was packed into a 7 mm outer diameter zirconia MAS rotor and spun at 4 kHz. This setup was chosen primarily for the high sensitivity needed for rapid identification and accurate quantification {as described in Klimke, K., Parkinson, M., Piel, C., Kaminsky, W., Spiess, H.W., Wilhelm, M., Macromol. Chem. Phys. 2006;207:382; Parkinson, M., Klimke, K., Spiess, H.W., Wilhelm, M., Macromol. Chem. Phys.2007;208:2128; Castignolles, P., Graf, R., Parkinson, M., Wilhelm, M., Gaborieau, M., Polymer 50 (2009) 2373}. Standard single- pulse excitation was employed utilising the NOE at short recycle delays of 3 s {as described in Pollard, M., Klimke, K., Graf, R., Spiess, H.W., Wilhelm, M., Sperber, O., Piel, C., Kaminsky, W., Macromolecules 2004;37:813; Klimke, K., Parkinson, M., Piel, C., Kaminsky, W., Spiess, H.W., Wilhelm, M., Macromol. Chem. Phys.2006;207:382} and the RS-HEPT decoupling scheme {Filip, X., Tripon, C., Filip, C., J. Mag. Resn.2005, 176, 239, Griffin, J.M., Tripon, C., Samoson, A., Filip, C., and Brown, S.P., Mag. Res. in Chem.2007 45, S1, S198}. A total of 16384 (16k) transients were acquired per spectra. Quantitative ¹³C{¹H} NMR spectra were processed, integrated and relevant quantitative properties determined from the integrals. All chemical shifts were internally referenced to the methyl isotactic pentad (mmmm) at 21.85 ppm. Characteristic signals corresponding to the incorporation of 1-butene were observed {A.J. Brandolini, D.D. Hills, “NMR spectra of polymers and polymer additives”, Marcel Deker Inc., 2000} and the comonomer content quantified. The amount of isolated 1-butene incorporated in PBP sequences was quantified using the integral of the ^B2 sites at 43.6 ppm accounting for the number of reporting sites per comonomer: B = I ^B2 / 2 The amount of consecutively incorporated 1-butene in PBBP sequences was quantified using the integral of the ^ ^B2B2 site at 40.5 ppm accounting for the number of reporting sites per comonomer: BB = 2 * I _{^ ^B2B2} In presence of BB the value of B was corrected for the influence of the ^B2 sites resulting from BB: B = (I ^B2 / 2) – BB/2 The total 1-butene content was calculated based on the sum of isolated and consecutively incorporated 1-butene: B_total = B + BB Characteristic signals corresponding to the incorporation of ethylene were observed {A.J. Brandolini, D.D. Hills, “NMR spectra of polymers and polymer additives”, Marcel Deker Inc., 2000} and the comonomer content quantified. The amount of isolated ethylene incorporated in PEP sequences was quantified using the integral of the Sββ sites at 24.3 ppm accounting for the number of reporting sites per comonomer: E = I_Sββ If characteristic signals corresponding to consecutive incorporation of ethylene in PEE sequence was observed the Sβδ site at 27.0 ppm was used for quantification: EE = I_Sβδ Characteristic signals corresponding to regio defects were observed. The presence of isolated 2,1-erythro regio defects was indicated by the presence of the two methyl sites at 17.7 and 17.2 ppm, by the methylene site at 42.4 ppm and confirmed by other characteristic sites. The presence of 2,1 regio defect adjacent an ethylene unit was indicated by the two inequivalent Sαβ signals at 34.8 ppm and 34.4 ppm respectively and the Tγγ at 33.7 ppm. The amount of isolated 2,1-erythro regio defects (P_{21e isolated}) was quantified using the integral of the methylene site at 42.4 ppm (I_e9): P_{21e isolated} = I_e9 If present the amount of 2,1 regio defect adjacent to ethylene (P_E21) was quantified using the methine site at 33.7 ppm (I_Tγγ): P_E21 = I_Tγγ The total ethylene content was then calculated based on the sum of ethylene from isolated, consecutively incorporated and adjacent to 2,1 regio defects: E_total = E + EE + P_E21 The amount of propene was quantified based on the S ^ ^ methylene sites at 46.7 ppm including all additional propene units not covered by S ^ ^ e.g. the factor 3*P_{21e isolated} accounts for the three missing propene units from isolated 2,1-erythro regio defects: P_total = I_{S ^ ^} + 3*P_{21e isolated} + B + 0.5*BB + E + 0.5*EE + 2*P_E21 The total mole fraction of 1-butene and ethylene in the polymer was then calculated as: fB = Btotal / ( Etotal + Ptotal + Btotal ) fE = Etotal / ( Etotal + Ptotal + Btotal ) The mole percent comonomer incorporation was calculated from the mole fractions: B [mol%] = 100 * fB E [mol%] = 100 * fE The weight percent comonomer incorporation was calculated from the mole fractions: B [wt%] = 100 * ( fB * 56.11 ) / ( (fE * 28.05) + (fB * 56.11) + ((1-(fE+fB)) * 42.08) ) E [wt%] = 100 * ( fE * 28.05 ) / ( (fE * 28.05) + (fB * 56.11) + ((1-(fE+fB)) * 42.08) ) The mole percent of isolated 2,1-erythro regio defects was quantified with respect to all propene: [21e] mol% = 100 * P_{21e isolated} / P_total The mole percent of 2,1 regio defects adjacent to ethylene was quantified with respect to all propene: [E21] mol% = 100 * P_E21 / P_total The total amount of 2,1 defects was quantified as following: [21] mol% = [21e] + [E21] Characteristic signals corresponding to other types of regio defects (2,1-threo, 3,1 insertion) were not observed {Resconi, L., Cavallo, L., Fait, A., Piemontesi, F., Chem. Rev. 2000, 100, 1253}. Metallocene synthesis Synthesis of MC-C1 Synthesis of this metallocene has been carried out as described in WO2019179959, MC- 2. Synthesis of MC-C2 Isopropylmalonic acid

A solution of 125 g of potassium hydroxide in 1000 cm³ of water was added to a solution of 110.0 g (544 mmol) of diethyl isopropylmalonate in 500 ml of methanol. The resulting mixture was refluxed for 5 h, then ethanol and methanol were distilled off. Then 1000 cm³ of water was added, and the obtained mixture was acidified by 12 M HCl to pH 1.0. Isopropylmalonic acid was extracted with 4 ^500 ml of ether. The combined extract was evaporated to dryness, and the residue was dried in vacuum. This procedure gave 76.4 g (96.1%) of isopropylmalonic acid as white solid. ¹H NMR (CDCl3): δ 9.72 (br.s, 2H), 3.24 (d, J = 8.3 Hz, 1H), 2.48-2.34 (m, 1H), 1.07 (d, J = 6.8 Hz, 6H). 2-Isopropylacrylic acid

Diethylamine (62.4 ml, 44.3 g, 0.606 mol) was added dropwise at 5 °C to a solution of isopropylmalonic acid (76.4 g, 523 mmol) in 750 ml of ethyl acetate. Paraform (22.1 g, 0.736 mol) was added to the obtained suspension. The resulting mixture was refluxed for 5 h, then cooled to 5 °C, and 350 ml of ether and 1000 cm³ of 2 M HCl were added. After mixing, the organic layer was separated, the aqueous layer was additionally extracted with 2 ^500 ml of ether. The combined organic phase was dried over Na2SO4 and then evaporated to dryness. The residue was purified by vacuum distillation to give 2- isopropylacrylic acid, bp 65 °C/4 mm Hg. Yield 57.0 g (95.5%) of a colorless liquid. ¹H NMR (CDCl3): δ 12.45 (br.s, 1H), 6.30 (s, 1H), 5.65 (t, 1H), 2.81 (septd, J = 6.9 Hz, J = 0.9 Hz, 1H), 1.11 (d, J = 6.9 Hz, 6H).¹³C NMR (CDCl3): δ 173.30, 146.47, 124.31, 28.94, 21.76. 6-tert-Butyl-5-methoxy-2-isopropylindan-1-one

114.1 g (1.0 mol) of 2-isopropylacrylic acid was added to Eaton's reagent obtained from 220 g of P₄O₁₀ and 1120 ml of MeSO₃H at 50 °C. 131.2 g (0.8 mol) of 1-tert-butyl-2- methoxybenzene was added dropwise to this mixture with vigorous stirring for ca.1 h at 50-53 °C (water bath temperature). The resulting mixture was stirred for 1 h at this temperature, then cooled to room temperature, and poured on a mixture of 1.5 liter of cold water and 3 kg of ice. The crude product was extracted with 3 ^600 ml of dichloromethane. The combined organic phase was washed by aqueous K₂CO₃, dried over K₂CO₃, filtered through a short pad of silica gel 60 (40-63 µm) and then evaporated to dryness. The residue was purified by vacuum distillation to give 193.8 g (93.0 %, ca.95% purity) of 6- tert-butyl-5-methoxy-2-isopropylindan-1-one as a yellowish oil (bp 150-190^oC /4 mm Hg). ¹H NMR (CDCl₃): δ 7.66 (s, 1H), 6.89 (s, 1H), 3.93 (s, 3H), 3.04 (dd, J = 17.4 Hz, J = 8.0 Hz, 1H), 2.84 (dd, J = 17.4 Hz, J = 3.8 Hz, 1H), 2.67-2.60 (m, 1H), 2.48-2.34 (m, 1H), 1.37 (s, 9H), 1.05 (d, J = 6.9 Hz, 3H), 0.77 (d, J = 6.9 Hz, 3H). ¹³C NMR (CDCl₃): δ 207.45, 164.44, 155.10, 138.54, 130.07, 121.69, 107.64, 55.14, 53.20, 35.00, 29.54, 28.87, 27.65, 20.96, 17.00. 4-Bromo-6-tert-butyl-2-isopropyl-5-methoxyindan-1-one

Bromine (20.8 ml, 64.9 g, 405.9 mmol) was added dropwise over 5 min to a mixture of 97.0 g (0.372 mol) of 6-tert-butyl-2-isopropyl-5-methoxyindan-1-one, 113.2 g of sodium acetate, 3.0 g of ⁿBu₄NI, 310 ml of dichloromethane, and 645 ml of water with vigorous stirring at 5 °C. This mixture was stirred at 5 °C for 2 h, then a solution of 52.2 g of sodium acetate in 290 ml of water was added followed by addition of 10.8 ml (33.7 g, 210.8 mmol) of bromine. The resulting mixture was additionally stirred for 1 h at this temperature and then washed by aqueous Na₂SO₃ to remove excess bromine. The crude product was extracted by 3 ^250 ml of dichloromethane. The combined organic extract was dried over K₂CO₃, evaporated to dryness, and the residue was dried in vacuum. This procedure gave 124.84 g (98.9%, ca. 95% purity) of a yellowish oil which was used without further purification. ¹H NMR (CDCl₃): δ 7.68 (s, 1H), 4.04 (s, 3H), 3.04 (dd, J = 17.9 Hz, J = 8.1 Hz, 1H), 2.80 (dd, J = 17.9 Hz, J = 3.9 Hz, 1H), 2.71-2.64 (m, 1H), 2.49-2.35 (m, 1H), 1.40 (s, 9H), 1.08 (d, J = 6.9 Hz, 3H), 0.80 (d, J = 6.8 Hz, 3H).¹³C NMR (CDCl₃): δ 207.21, 162.59, 154.47, 145.24, 133.82, 121.03, 116.56, 61.54, 53.32, 35.56, 30.54, 29.41, 28.94, 20.78, 17.17. 6-tert-Butyl-2-isopropyl-5-methoxy-4-(3,5-dimethylphenyl)-indan-1-one

A mixture of 124.84 g (368.0 mmol) of 4-bromo-6-tert-butyl-2-isopropyl-5-methoxyindan- 1-one, 69.7 g (464.7 mmol, 1.26 equiv.) of 3,5-Me2C6H3B(OH)2, 1.9 g (3.72 mmol, 1 mol. %) of Pd(P^tBu3)2, 118.3 g of Na2CO3, 600 ml of 2-methyltetrahydrofurane and 540 ml of water was refluxed for 6 h. Then, 500 ml of water was added, the organic layer was separated, and the aqueous layer was extracted with 300 ml of dichloromethane. The combined organic extract was dried over K₂CO₃ and then evaporated to dryness to give slightly yellowish solid mass. The product was isolated by flash-chromatography on silica gel 60 (40-63 µm, eluent: hexanes-dichloromethane = 1:1 and then 1:5, vol.). Yield 121.55 g (90.6%, purity ca.95%) of a yellowish crystalline material. ¹H NMR (CDCl₃): δ 7.71 (s, 1H), 7.04 (s, 1H), 7.03 (s, 2H), 3.31 (s, 3H), 2.87 (dd, J = 18.5 Hz, J = 8.8 Hz, 1H), 2.65-2.54 (dd and m, 2H), 2.43-2.34 (s and m, 7H), 1.42 (s, 9H), 0.99 (d, J = 6.9 Hz, 3H), 0.77 (d, J = 6.8 Hz, 3H).¹³C NMR (CDCl₃): δ 208.19, 163.34, 153.44, 143.11, 138.08, 136.33, 132.64, 132.12, 129.08, 127.20, 120.93, 77.00, 60.46, 53.37, 35.33, 30.50, 28.88, 27.38, 21.39, 20.90, 17.25. 5-tert-Butyl-2-isopropyl-6-methoxy-7-(3,5-dimethylphenyl)-1H-indene

NaBH4 (18.9 g, 0.5 mol, 1.5 equiv.) was added to a solution of 121.55 g (333.45 mmol) of 6-tert-butyl-2-isopropyl-5-methoxy-4-(3,5-dimethylphenyl)-indan-1-one in 600 ml of THF cooled to 5 °C. MeOH (300 ml) was added dropwise to this mixture over ca.5 h at 5 °C, and the resulting mixture was stirred overnight at room temperature. Then, this mixture was evaporated to dryness, 1000 ml of dichloromethane and 1000 ml water were added to the residue, and the so obtained mixture was acidified with 2 M HCl to pH~6.5. The organic layer was separated, the aqueous layer was additionally extracted with 100 ml of dichloromethane. The combined organic phase was passed through a pad (~30 ml) of silica gel 60 (40-63 µm; eluent: dichloromethane) to get rid of most of the palladium black. The obtained elute was evaporated to dryness to give a grey solid mass. To a solution of this mass in 1000 ml of toluene 1.0 g of TsOH was added. This mixture was refluxed with Dean-Stark head for 10 min and then cooled to room temperature using water bath. The formed solution was washed with 10% Na₂CO₃, the organic layer was separated, the aqueous layer was extracted with 300 ml of dichloromethane. The combined organic phase was dried over K₂CO₃ and then evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 µm, hexanes-dichloromethane = 5:1) followed by recrystallization from n-hexane (hot→ –30 °C). This procedure gave 96.93 g (83.4%) of pure 5-tert-butyl-7-(3,5-dimethylphenyl)-2-isopropyl-6-methoxy-1H-indene. ¹H NMR (CDCl₃): δ 7.24 (s, 1H), 7.09 (s, 2H), 6.99 (s, 1H), 6.46 (m, 1H), 3.24 (s, 3H), 3.15 (m, 2H), 2.68 (sept, J = 6.8 Hz, 1H), 2.37 (s, 6H), 1.43 (s, 9H), 1.14 (d, J = 6.8 Hz, 6H). ¹³C NMR (CDCl₃): δ 156.43, 154.33, 141.34, 140.95, 140.23, 138.29, 137.69, 131.99, 128.49, 127.22, 123.86, 117.32, 60.67, 39.15, 35.13, 31.00, 30.04, 22.64, 21.44. [6-tert-butyl-4-(3,5-dimethylphenyl)-2-isopropyl-5-methoxy-1H-inden-1-yl] chlorodimethylsilane

ⁿBuLi in hexanes (2.5 M, 8.0 ml, 20.0 mmol) was added in one portion to a solution of 5- tert-butyl-7-(3,5-dimethylphenyl)-2-isopropyl-6-methoxy-1H-indene (6.97 g, 20.0 mmol) in 200 ml of ether cooled to –50 °C. This mixture was stirred overnight at room temperature, then the resulting yellow suspension was cooled to –50 °C, then dichlorodimethylsilane (12.1 ml, 12.95 g, 100.3 mmol, 5.02 equiv.) was added in one portion followed by 5 ml of THF. The resulting mixture was stirred overnight at room temperature, then filtered through a glass frit (G3), and the filter cake was washed with 2 ^50 ml of toluene. The combined filtrate was evaporated to dryness to give [6-tert-butyl-4-(3,5-dimethylphenyl)-2-isopropyl- 5-methoxy-1H-inden-1-yl]chlorodimethylsilane as a yellowish thick oil which was used without further purification. ¹H NMR (CDCl3): δ 7.40 (s, 1H), 7.10 (br.s, 2H), 7.00 (m, 1H), 6.44 (s, 1H), 3.76 (s, 1H), 3.23 (s, 3H), 2.89 (sept.d, J = 6.8 Hz, J = 1.3 Hz, 1H), 2.39 (s, 6H), 1.43 (s, 9H), 1.20 (d, J = 6.7 Hz, 3H), 1.12 (d, J = 6.9 Hz, 3H), 0.43 (s, 3H), 0.12 (s, 3H). ¹³C NMR (CDCl3): δ 157.53, 155.85, 143.40, 137.91, 137.60, 136.43, 128.33, 127.92, 127.89, 122.52, 121.06, 60.45, 47.72, 35.16, 31.16, 29.45, 24.43, 21.45, 21.17, 1.35, -0.77.

[4,8-Bis(3,5-dimethylphenyl)-2-methyl-1,5,6,7-tetrahydro-s-indacen-1-yl][6-tert-butyl-4- (3,5-dimethylphenyl)-5-methoxy-2-isopropyl-1H-inden-1-yl]dimethylsilane

ⁿBuLi in hexanes (2.5 M, 8.0 ml, 20.0 mmol) was added in one portion to a suspension of 4,8-di(3,5-dimethylphenyl)-6-methyl-1,2,3,5-tetrahydro-s-indacene (7.57 g, 20.0 mmol) in a mixture of 120 ml of ether and 25 ml of THF, cooled to –50 °C. The resulting mixture was stirred overnight at room temperature, then the so obtained light-orange solution containing a large amount of orange precipitate was cooled to –50 °C, and 200 mg of CuCN was added. The obtained mixture was stirred for 0.5 h at –25 °C, then a solution of ca. 20.0 mmol of [6-tert-butyl-4-(3,5-dimethylphenyl)-2-isopropyl-5-methoxy-1H-inden-1- yl]chlorodimethylsilane (prepared above) in 200 ml of Et2O was added in one portion. This mixture was stirred overnight at room temperature, then filtered through a pad of silica gel 60 (40-63 µm), which was additionally washed with 2 ^50 ml of Et₂O. The combined organic elute was evaporated to dryness, and the residue was dried under vacuum at elevated temperature to give 15.58 g (99.5% of ca.85% purity) of the title product (ca.63:37 mixture of the stereoisomers) as a slightly yellowish solid glass which was used without further purification. Anti-dimethylsilanediyl[2-methyl-4,8-di(3,5-dimethylphenyl)-1,5,6,7-tetrahydro-s-indacen- 1-yl][2-isopropyl-4-(3,5-dimethylphenyl)-5-methoxy-6-tert-butylinden-1-yl] zirconium dichloride (MC-C2)

ⁿBuLi in hexanes (2.5 M, 14.8 ml, 37.0 mmol) was added in one portion at room temperature to a yellowish solution of [4,8-bis(3,5-dimethylphenyl)-2-methyl-1,5,6,7- tetrahydro-s-indacen-1-yl][6-tert-butyl-4-(3,5-dimethylphenyl)-5-methoxy-2-isopropyl-1H- inden-1-yl]dimethylsilane (14.46 g, ca.18.46 mmol) in 95 ml of ⁿBu₂O. This mixture was stirred overnight at room temperature, then the resulting red solution was cooled to 0 °C in an ice-bath, then ZrCl₄ (4.3 g, 18.45 mmol) was added. The reaction mixture was stirred for 24 h at room temperature to give orange-red solution with precipitate of LiCl. This mixture was evaporated to dryness (to the state of red foam), and the residue was treated with 100 ml of warm toluene. The obtained suspension was filtered through glass frit (G4), the filter cake was washed with 2 ^20 ml of warm toluene. The filtrate was evaporated to ca.20 ml, then 30 ml of n-hexane was added to this solution. The yellow solid precipitated from this solution overnight at room temperature was collected and dried under vacuum. This procedure gave 3.3 g of anti-complex. The mother liquor was evaporated to the state of oil, and the residue was dissolved in 30 ml of n-hexane. The yellow powder precipitated from this solution overnight at room temperature was collected and dried under vacuum. This procedure gave 3.4 g of anti-complex. The mother liquor was evaporated to dryness, and the residue was dissolved in 30 ml of n-hexane. Yellow powder precipitated from this solution overnight at –25 °C was collected and dried under vacuum. This procedure gave 1.55 g of anti-complex. The mother liquor was again evaporated to dryness, and the residue was dissolved in 20 ml of n-pentane. Yellow powder precipitated from this solution overnight at –25 °C was collected and dried under vacuum. This procedure gave 0.85 g of anti-complex. Thus, the total yield of anti-dimethylsilanediyl[2-methyl-4,8-di(3,5- dimethylphenyl)-1,5,6,7-tetrahydro-s-indacen-1-yl][2-isopropyl-4-(3,5-dimethylphenyl)-5- methoxy-6-tert-butylinden-1-yl]zirconium dichloride isolated in this synthesis was 9.1 g (52.3%). Anal. calc. for C₅₆H₆₄Cl₂OSiZr: C, 71.30; H, 6.84. Found: C, 71.38; H, 7.00. ¹H NMR (CDCl₃): δ 7.42 (s, 1H), 7.11 (s, 1H), 6.99 (s, 2H), 6.97 (s, 1H), 6.93 (s, 1H), 6.88 (s, 1H), 6.61 (s, 1H), 7.8-6.7 (very br.s, 4H), 3.36 (s, 3H), 3.21-3.04 (m, 2H), 3.04-2.84 (m, 2H), 2.54-2.40 (m, 1H), 2.43, 2.36, 2.35 and 2.28 (4s, sum 21H), 2.05-1.92 (m, 1H), 1.80- 1.64 (m, 1H), 1.34 (s, 9H), 1.16 (s, 3H), 1.08 (d, J = 6.4 Hz, 3H), 0.84 (d, J = 6.6 Hz, 3H), -0.14 (s, 3H).¹³C NMR (CDCl₃): δ 159.89, 146.50, 144.76, 144.43, 142.85, 141.58, 138.34, 138.15, 137.32, 136.84, 135.47, 132.74, 132.31, 132.19, 131.26, 129.38, 129.16, 128.97, 128.81, 128.74, 127.60, 126.90, 125.09, 121.69, 121.25, 116.29, 83.13, 81.42, 62.40, 35.67, 33.93, 32.61, 30.43, 29.57, 28.91, 26.04, 21.52, 21.41, 21.25, 20.41, 20.05, 4.07, 3.05. Synthesis of MC-I1 Ethylmalonic acid

A solution of 196.4 g (3.5 mol) of potassium hydroxide in 1000 cm³ of water was added to a solution of 188.2 g (1.0 mol) of diethyl ethylmalonate in 500 ml of methanol. The resulting mixture was refluxed for 5 h, then ethanol and methanol were distilled off. Then, 1000 cm³ of water was added and the obtained mixture was acidified with 12 M HCl to pH 1.0. Ethylmalonic acid was extracted with 5 ^300 ml of ether. The combined extract was evaporated to dryness and the residue was dried under vacuum. This procedure gave 120.2 g (91.0%) of ethylmalonic acid as white solid. ¹H NMR (DMSO-d₆): δ 4.28 (br.s, 2H), 3.12 (d, J = 7.4 Hz, 1H), 1.71 (quin, J = 7.40 Hz, 2H), 0.86 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl₃): δ 171.12, 53.36, 22.01, 11.95. 2-Ethylacrylic acid

Diethylamine (108.2 ml, 76.82 g, 1.05 mol) was added dropwise at 5 °C to a solution of ethylmalonic acid (118.8 g, 899.2 mmol) in 1300 ml of ethyl acetate. Paraform (38.4 g, 1.28 mol) was added to the obtained suspension. The resulting mixture was refluxed for 5 h, then cooled to 5 °C, then 600 ml of ether and 1700 cm³ of 2 M HCl were added. After mixing, the organic layer was separated, the aqueous layer was additionally extracted with 2 ^700 ml of ether. The combined organic extract was dried over Na2SO4 and then carefully evaporated to dryness. The residue was purified by vacuum distillation to give 2- ethylacrylic acid, bp 75-77^oC/6 mm Hg. Yield 79.8 g (88.6%) of a colorless liquid. ¹H NMR (CDCl₃): δ 12.55 (br.s, 1H), 6.28 (m, 1H), 5.64 (m, 1H), 2.32 (qm, J = 7.5 Hz, 2H), 1.08 (t, J = 7.5 Hz, 3H). 6-tert-Butyl-5-methoxy-2-ethylindan-1-one

2-ethylacrylic acid (47.6 g, 475.5 mmol, 1.27 equiv.) was added to Eaton's reagent obtained from 103.5 g of P4O10 and 520 ml of MeSO3H at 50 °C. To this rapidly stirred mixture, 1-tert-butyl-2-methoxybenzene (61.7 g, 375.7 mmol) was added dropwise over ca. 1 h at 50-53 °C (hot water bath). The resulting mixture was stirred for 1 h at this temperature, then cooled to room temperature, and poured on a mixture of 1.0 liter of cold water and 1 kg of ice. The crude product was extracted with 3 ^400 ml of dichloromethane. The combined organic extract was washed with aqueous K2CO3, dried over K2CO3, filtered through a short pad of silica gel 60 (40-63 µm) and then evaporated to dryness. The residue was purified by vacuum distillation to give 81.18 g (87.7 %, ca.90% purity) of 6- tert-butyl-5-methoxy-2-ethylindan-1-one as a yellowish oil (bp 150-170^oC/5 mm Hg). ¹H NMR (CDCl3): δ 7.65 (s, 1H), 6.85 (s, 1H), 3.90 (s, 3H), 3.20 (dd, J = 17.2 Hz, J = 7.7 Hz, 1H), 2.71 (dd, J = 17.2 Hz, J = 3.6 Hz, 1H), 2.59-2.51 (m, 1H), 1.99-1.87 (m, 1H), 1.54- 1.41 (m, 1H), 1.35 (s, 9H), 0.97 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl3): δ 207.59, 164.52, 154.75, 138.65, 129.31, 121.87, 107.72, 55.15, 48.86, 35.00, 31.93, 29.54, 24.61, 11.56. 4-Bromo-6-tert-butyl-2-ethyl-5-methoxyindan-1-one

Bromine (18.5 ml, 57.4 g, 359.1 mmol) was added dropwise over 5 min at 5 °C to a mixture of 6-tert-butyl-2-ethyl-5-methoxyindan-1-one (81.18 g, 329.5 mmol), 100.4 g of sodium acetate, 3.0 g of ⁿBu₄NI, 280 ml of dichloromethane, and 570 ml of water. This mixture was stirred for 2 h at 5 °C, then a solution of 46.3 g of sodium acetate in 260 ml of water was added followed by addition of 9.7 ml (30.1 g, 188.3 mmol) of bromine. The resulting mixture was additionally stirred for 1 h at this temperature and then washed by aqueous Na₂SO₃ to remove excess bromine. The crude product was extracted with 3 ^250 ml of dichloromethane. The combined organic extract was dried over K₂CO₃, evaporated to dryness, and the residue was dried under vacuum. This procedure gave 105.3 g (98.1%, ca. 90% purity) of 4-bromo-6-tert-butyl-2-ethyl-5-methoxyindan-1-one as a yellowish oil which was used without further purification. ¹H NMR (CDCl₃): δ 7.69 (s, 1H), 4.03 (s, 3H), 3.21 (dd, J = 17.6 Hz, J = 7.8 Hz, 1H), 2.70 (dd, J = 17.6 Hz, J = 3.7 Hz, 1H), 2.66-2.58 (m, 1H), 2.03-1.91 (m, 1H), 1.60-1.47 (m, 1H), 1.40 (s, 9H), 1.03 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl₃): δ 207.14, 162.57, 154.07, 145.20, 133.07, 121.13, 116.50, 61.45, 48.79, 35.46, 33.36, 30.45, 24.34, 11.43. 6-tert-Butyl-2-ethyl-5-methoxy-4-(3,5-dimethylphenyl)-indan-1-one

A mixture of 64.08 g (197.0 mmol) of 4-bromo-6-tert-butyl-2-ethyl-5-methoxyindan-1-one, 37.32 g (248.8 mmol, 1.26 equiv.) of 3,5-dimethylphenylboronic acid, 1.02 g (2.0 mmol, 1 mol.%) of Pd(P^tBu₃)₂, 63.4 g of Na₂CO₃, 325 ml of 2-methyltetrahydrofurane, and 290 ml of water was refluxed for 6 h. Then 500 ml of water was added, the organic layer was separated, and the aqueous layer was extracted with 200 ml of dichloromethane. The combined organic extract was dried over K₂CO₃ and then evaporated to dryness to give slightly yellowish oil. The product was isolated by flash-chromatography on silica gel 60 (40-63 µm, eluent: hexanes-dichloromethane = 1:1 and then 1:5, vol.). Yield 62.95 g (91.2%, purity ca.95%) of a slightly yellowish oil. ¹H NMR (CDCl3): δ 7.73 (s, 1H), 7.03 (s, 1H), 7.02 (s, 2H), 3.32 (s, 3H), 3.06 (dd, J = 18.3 Hz, J = 8.6 Hz, 1H), 2.57-2.47 (m, 2H), 2.39 (s, 6H), 2.00-1.87 (m, 1H), 1.54-1.40 (m, 1H), 1.42 (s, 9H), 0.95 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl3): δ 208.30, 163.42, 153.15, 143.21, 138.06, 136.27, 132.68, 131.42, 129.07, 127.17, 121.11, 60.47, 49.00, 35.33, 31.69, 30.49, 24.48, 21.36, 11.67. 5-tert-Butyl-2-ethyl-6-methoxy-7-(3,5-dimethylphenyl)-1H-indene

NaBH₄ (10.2 g, 269.6 mmol, 1.5 equiv.) was added to a solution of 62.95 g (179.6 mmol) of 6-tert-butyl-2-ethyl-5-methoxy-4-(3,5-dimethylphenyl)-indan-1-one in 300 ml of THF cooled to 5 °C. To this mixture 150 ml of MeOH was added dropwise over ca.5 h at 5 °C, and the resulting mixture was stirred overnight at room temperature. Then, this mixture was evaporated to dryness, 700 ml of dichloromethane and 700 ml water were added to the residue, and the so obtained mixture was acidified with 2 M HCl to pH~6.5. The organic layer was separated, the aqueous layer was additionally extracted with 100 ml of dichloromethane. The combined organic extract was passed through a pad (~30 ml) of silica gel 60 (40-63 µm; eluent: dichloromethane) to get rid of most of the palladium black. The obtained elute was evaporated to dryness to give a grey oil. This oil was dissolved in 300 ml of toluene and TsOH (0.3 g) was added to it. This mixture was refluxed with Dean- Stark head for 10 min and then cooled to room temperature using a water bath. The formed solution was washed with 10% Na₂CO₃, the organic layer was separated, the aqueous layer was extracted with 150 ml of dichloromethane. The combined organic extract was dried over K2CO3 and then evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 µm, hexanes-dichloromethane = 10:1) followed by vacuum distillation to give 53.14 g (88.5%) of 5-tert-butyl-2-ethyl-6-methoxy-7-(3,5- dimethylphenyl)-1H-indene as a yellowish oil (bp 175-195^oC/2 mm Hg). ¹H NMR (CDCl3): δ 7.22 (s, 1H), 7.09 (s, 2H), 6.99 (s, 1H), 6.45 (t, J = 1.4 Hz, 1H), 3.25 (s, 3H), 3.13 (s, 2H), 2.41 (q, J = 7.4 Hz, 2H), 2.37 (s, 6H), 1.44 (s, 9H), 1.14 (d, J = 7.4 Hz, 3H). ¹³C NMR (CDCl3): δ 154.25, 151.76, 141.51, 140.88, 140.43, 138.31, 137.66, 131.91, 128.46, 127.20, 124.97, 117.17, 60.66, 41.00, 35.13, 31.01, 24.25, 21.43, 13.47. [6-tert-Butyl-4-(3,5-dimethylphenyl)-2-ethyl-5-methoxy-1H-inden-1-yl]chloro dimethylsilane

ⁿBuLi in hexanes (2.5 M, 10.9 ml, 27.25 mmol) was added in one portion to a solution of of 5-tert-butyl-7-(3,5-dimethylphenyl)-2-ethyl-6-methoxy-1H-indene (9.05 g, 27.06 mmol) in 200 ml of ether cooled to –50 °C. This mixture was stirred overnight at room temperature, then the resulting orange-yellow solution was cooled to –50 °C, then dichlorodimethylsilane (16.3 ml, 17.44 g, 135.1 mmol, 5.0 equiv.) was added to it in one portion. The resulting mixture was stirred overnight at room temperature, then filtered through a glass frit (G3), and the filter cake was washed with 2 ^50 ml of toluene. The combined filtrate was evaporated to dryness to give the title compound as a yellowish thick oil that was used without further purification. ¹H NMR (CDCl₃): δ 7.39 (s, 1H), 7.09 (s, 2H), 6.99 (s, 1H), 6.45 (s, 1H), 3.65 (s, 1H), 3.24 (s, 3H), 2.67-2.46 (m, 2H), 2.38 (s, 6H), 1.43 (s, 9H), 1.15 (t, J = 7.5 Hz, 3H), 0.43 (s, 3H), 0.15 (s, 3H).¹³C NMR (CDCl₃): δ 155.83, 152.58, 143.55, 137.96, 137.58, 137.55, 136.53, 128.33, 127.90, 127.74, 124.52, 121.00, 60.46, 48.34, 35.16, 31.17, 24.71, 21.44, 13.76, 1.21, -0.66. [4,8-Bis(3,5-dimethylphenyl)-2-methyl-1,5,6,7-tetrahydro-s-indacen-1-yl][6-tert-butyl-4- (3,5-dimethylphenyl)-5-methoxy-2-ethyl-1H-inden-1-yl]dimethylsilane

2.47 ml (6.17 mmol) of 2.5 M ⁿBuLi in hexanes was added in one portion to a suspension of 2.33 g (6.15 mmol) of 4,8-di(3,5-dimethylphenyl)-6-methyl-1,2,3,5-tetrahydro-s- indacene in a mixture of 27 ml of ether and 8 ml of THF cooled to -50 °C. The resulting mixture was stirred overnight at room temperature, then the so obtained light-orange solution with a large amount of orange precipitate was cooled to -50 °C, and 45 mg of CuCN was added. The reaction mixture temperature was allowed to rise to -17 °C for ca. 0.5 h, and then a solution of 2.65 g (6.2 mmol) of [6-tert-butyl-4-(3,5-dimethylphenyl)-2- ethyl-5-methoxy-1H-inden-1-yl]chlorodimethylsilane in 45 ml of ether was added in one portion to this suspension. This mixture was stirred overnight at room temperature, then evaporated to dryness. The residue was dissolved in a mixture of 90 ml of hexane and 10 ml of dichloromethane, the obtained solution was filtered through a pad of silica gel 60 (40- 63 µm, 15 ml) (which was additionally washed by 2x25 ml of a 10:1 mixture of hexane and dichloromethane), the elute was evaporated to dryness, and the residue was dried in vacuum to give 5.0 g of the title product (a ca.60:40 mixture of the stereoisomers) as a white powder which was used without further purification. Anti-dimethylsilanediyl[2-methyl-4,8-di(3,5-dimethylphenyl)-1,5,6,7-tetrahydro-s-indacen- 1-yl][2-ethyl-4-(3,5-dimethylphenyl)-5-methoxy-6-tert-butylinden-1-yl] zirconium dichloride (MC-I1)

5.0 ml (12.5 mmol) of 2.5 M ⁿBuLi in hexanes was added in one portion to a yellowish solution of 5.0 g (ca. 6.2 mmol) of [4,8-bis(3,5-dimethylphenyl)-2-methyl-1,5,6,7- tetrahydro-s-indacen-1-yl][6-tert-butyl-4-(3,5-dimethylphenyl)-5-methoxy-2-ethyl-1H- inden-1-yl]dimethylsilane in 32 ml of ⁿBu₂O at 0 °C. This mixture was stirred overnight at room temperature, then the resulting red turbid solution was cooled to 0 °C in an ice-bath, and 1.45 g (6.2 mmol) of ZrCl₄ was added. The reaction mixture was stirred for 24 h at room temperature to give an orange-red suspension. This suspension was evaporated to dryness (to the state of an orange powder). To this solid 40 ml of pentane was added. The yellow precipitate fallen from this mixture at room temperature was collected and dried in vacuum. This procedure gave 4.2 g of a 99:1 mixture of anti- and syn-zirconocene dichlorides contaminated with ca.0.52 g of LiCl. Therefore, the title complex was obtained in ca.63% yield. Synthesis of MC-I2 Synthesis of 2-n-propyl-5-tert-butyl-6-methoxy-7-(3,5-dimethylphenyl)-1H-indene Method 1 2-Bromo-6-tert-butyl-4-(3,5-dimethylphenyl)-5-methoxyindan-1-ol

Water (20 ml) was added to a solution of 5-tert-butyl-7-(3,5-dimethylphenyl)-6-methoxy- 1H-indene (61.29 g, 0.2 mol) in a mixture of 550 ml of DMSO and 300 ml of THF. Then, 37.38 g (210 mmol, 1.05 equiv.) of N-bromosuccinimide was added in aliquots over 90 min. After that, the obtained mixture was stirred overnight at room temperature. Then, 1200 ml of water and 600 ml of dichloromethane were added. The organic layer was separated, and the aqueous layer was additionally extracted with 2 ^150 ml of dichloromethane. The combined organic extract was washed with 6 ^1000 ml of water, dried over Na₂SO₄, and evaporated to dryness. The residue was dissolved in 300 ml of hexane and left for crystallization for 30 min at 5 °C. The obtained white crystals were filtered off (G3), washed with n-hexane and dried in vacuum. This procedure gave 64.89 g of the title product. The combined filtrate was evaporated to dryness, and the residue was recrystallized in the same way from 35 ml of n-hexane. This procedure gave additional 8.07 g of the title product. Thus, the total yield of 2-bromo-6-tert-butyl-4-(3,5-dimethylphenyl)-5- methoxyindan-1-ol isolated in this synthesis was 72.96 g (90.4%). ¹H NMR (CDCl₃): δ 7.34 (s, 1H), 6.99-6.94 (2s, sum 3H), 5.29 (dd, J = 6.2 Hz, J = 6.0 Hz, 1H), 4.17 (ddd, J = 7.7 Hz, J = 7.4 Hz, J = 6.0 Hz, 1H), 3.30 (dd, J = 16.4 Hz, J = 7.4 Hz, 1H), 3.24 (s, 3H), 3.06 (dd, J = 16.4 Hz, J = 7.7 Hz, 1H), 2.40 (d, J = 6.2 Hz, 1H), 2.35 (s, 6H), 1.42 (s, 9H). ¹³C NMR (CDCl₃): δ 158.21, 142.68, 137.99, 137.83, 136.83, 135.68, 131.99, 128.82, 127.14, 121.07, 83.74, 60.37, 54.83, 39.88, 35.30, 30.73, 21.38. 2-Bromo-5-tert-butyl-7-(3,5-dimethylphenyl)-6-methoxy-1H-indene

TsOH (2.0 g) was added to a solution of 2-bromo-6-tert-butyl-4-(3,5-dimethylphenyl)-5- methoxyindan-1-ol (72.96 g, 180.88 mmol) in 600 ml of toluene, preheated to ca.60 °C. This mixture was refluxed with Dean-Stark head for 7 min. Then, the reaction mixture was quickly cooled to room temperature using an ice-water bath. The formed solution was washed with 10% Na₂CO₃, the organic layer was separated, and the aqueous layer was extracted with 200 ml of dichloromethane. The combined organic extract was dried over K₂CO₃ and then evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 µm, hexanes-dichloromethane = 2:1) to give 70.51 g (ca. 100%) of 2-bromo-5-tert-butyl-7-(3,5-dimethylphenyl)-6-methoxy-1H-indene as a light-yellow glassy solid. ¹H NMR (CDCl₃): δ 7.24 (s, 1H), 7.05 (s, 2H), 6.99 (s, 1H), 6.87 (t, J = 1.6 Hz, 1H), 3.41 (d, J = 1.6 Hz, 2H), 3.26 (s, 3H), 2.36 (s, 6H), 1.43 (s, 9H).¹³C NMR (CDCl₃): δ 155.18, 141.55, 141.19, 138.79, 137.91, 137.46, 132.79, 131.78, 128.82, 126.95, 123.25, 117.55, 60.65, 45.50, 35.19, 30.88, 21.40. 5/6-tert-Butyl-7/4-(3,5-dimethylphenyl)-6/5-methoxy-2-propyl-1H-indene

[1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene](triphenylphosphine)dichloronickel(II) (NiCl₂(IPr)PPh₃ , 0.45 g, 0.57 mmol, 2.5 mol.%) was added to a mixture of 2-bromo-5-tert- butyl-7-(3,5-dimethylphenyl)-6-methoxy-1H-indene (8.1 g, 21 mmol) and ⁿPrMgBr in THF (1.0 M, 105 ml, 5 equiv.). This solution was refluxed for 30 min. The dark solution formed was poured into a mixture of 200 g of ice and 200 ml of water. Then, 50 ml of 1.0 M HCl was added. The organic layer was separated. The aqueous layer was extracted with 4x100 ml of dichloromethane. The combined organic extract was dried over K2CO3 and then evaporated to dryness. The product was isolated by flash-chromatography on silica gel 60 (40-63 µm, eluent: hexanes-dichloromethane = 10:1, vol). Yield 7.0 g of a slightly yellowish oil. This product was a mixture of two isomeric indenes contaminated with ca.9% of the debromination by-product. To reduce content of the debromination by-product, a mixture of this crude product (7.0 g) with 0.25 g TsOH in 100 ml of toluene was refluxed for 30 min. After the solution was cooled to room temperature 200 ml of an aqueous K₂CO₃ was added, the organic layer was separated, and the aqueous layer was extracted with 2x40 ml of toluene. The combined organic extract was dried over K₂CO₃ and then evaporated to dryness. The obtained material was distilled under reduced pressure to give 5.5 g (75%, purity ca.97%) of a ca.2:3 mixture of two isomers as a colorless oil, b.p.160–210°C/3 mm Hg. Minor isomer: ¹H NMR (CDCl3): δ 7.34 (s, 1H), 7.10 (s, 2H), 6.98 (br. s, 1H), 6.34 (s, 1H), 3.30 (s, 2H), 3.25 (s, 3H), 2.38-2.34 (m, 8H), 1.59-1.50 (m, 2H), 1.44 (s, 9H), 0.91 (t, J = 7.3 Hz, 3H).¹³C NMR (CDCl3): δ 156.08, 151.14, 144.16, 137.87, 137.72, 137.53, 137.43, 131.86128.28, 127.84, 125.40, 120.81, 60.44, 41.13, 35.04, 33.52, 31.11, 22.44, 21.42, 14.01. Major isomer: ¹H NMR (CDCl3): δ 7.23 (s, 1H), 7.09 (s, 2H), 6.98 (br. s, 1H), 6.45 (m, 1H), 3.25 (s, 3H), 3.12 (s, 2H), 2.38-2.34 (m, 8H), 1.59-1.50 (m, 2H), 1.44 (s, 9H), 0.91 (t, J = 7.3 Hz, 3H).¹³C NMR (CDCl3): δ 154.24, 149.97, 141.56, 140.85, 140.44, 138.30, 137.65, 131.87, 128.46, 127.20, 126.05, 117.13, 60.65, 41.04, 35.12, 33.29, 31.00, 22.29, 21.42, 13.94. [6-tert-Butyl-4-(3,5-dimethylphenyl)-5-methoxy-2-propyl-1H-inden-1-yl] chlorodimethylsilane

ⁿBuLi in hexanes (2.5 M, 6.3 ml, 16.0 mmol) was added in one portion to a solution of 5- tert-butyl-7-(3,5-dimethylphenyl)-6-methoxy-2-propyl-1H-indene (5.5 g, 15.78 mmol) in a mixture of 120 ml of ether and 10 ml of THF cooled to –50 °C. This mixture was stirred overnight at room temperature, then the resulting yellow solution was cooled to –50 °C, and dichlorodimethylsilane (9.5 ml, 10.07 g, 78.0 mmol, 5.0 equiv.) was added in one portion. The resulting mixture was stirred overnight at room temperature, then filtered through a glass frit (G3), and the filter cake was washed with 2x50 ml of toluene. The combined filtrate was evaporated to dryness to give the title product which was used without further purification. ¹H NMR (CDCl₃): δ 7.39 (s, 1H), 7.09 (br. s, 2H), 6.99 (s, 1H), 6.45 (s, 1H), 3.64 (s, 1H), 3.25 (s, 3H), 2.54-2.49 (m, 2H), 2.38 (s, 6H), 1.68-1.48 (m, 2H), 1.43 (s, 9H), 0.91 (t, J = 7.3 Hz, 3H), 0.42 (s, 3H), 0.15 (s, 3H).¹³C NMR (CDCl₃): δ 155.79, 150.92, 143.54, 137.95, 137.56, 137.49, 136.54, 128.31, 127.89, 127.65, 125.43, 120.99, 60.46, 48.22, 35.16, 33.72, 31.16, 22.75, 21.44, 14.06, 1.19, -0.64. Method 2 n-Propylmalonic acid

A solution of 99.7 g (1.78 mol) of potassium hydroxide in 500 cm³ of water was added to a solution of 101.1 g (0.5 mol) of diethyl n-propylmalonate in 100 ml of methanol. The resulting mixture was refluxed for 5 h, then ethanol and methanol were distilled off. Then, 500 cm³ of water was added, and the obtained mixture was acidified by 12 M HCl to pH 1.0. Propylmalonic acid was extracted with 4x400 ml of ether. The combined extract was evaporated to dryness, and the residue was dried in vacuum. This procedure gave 76.4 g (ca.100%) of n-propylmalonic acid which was used without further purification. 2-n-Propylacrylic acid

Diethylamine (42.4 g, 0.58 mol) was added dropwise at 5 °C to a solution of ca.0.5 mol of n-propylmalonic acid in 650 ml of ethyl acetate. To the obtained suspension, 21.3 g (0.71 mol) of paraform was added. The resulting mixture was refluxed for 5 h, then cooled to 5^oC, and 350 ml of ether and 1000 cm³ of 2 M HCl were added. After mixing, the organic layer was separated, the aqueous layer was additionally extracted with 2x500 ml of ether. The combined organic extract was dried over Na2SO4 and then evaporated to dryness. The residue was purified by vacuum distillation to give 2-n-propylacrylic acid, bp 67-70^oC/4 mm Hg. Yield 46.1 g (80%) of a colorless liquid. ¹H NMR (CDCl₃): δ 12.54 (br.s, 1H), 6.30 (m, 1H), 5.65 (m, 1H), 2.29 (t, J = 7.3 Hz, 2H), 1.52 (sext, J = 7.4 Hz, 2H), 0.94 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl₃): δ 173.24, 140.02, 127.04, 33.44, 21.48, 13.58. 6-tert-Butyl-5-methoxy-2-n-propylindan-1-one

2-n-propylacrylic acid (46.1 g, 0.4 mol) was added to the Eaton's reagent obtained from 55 g of P4O10 and 280 ml of MeSO3H at 50 °C. To this mixture 52.5 g (0.32 mol) of 1-tert- butyl-2-methoxybenzene was added dropwise by vigorous stirring for ca.1 h at 50-53 °C. The resulting mixture was stirred for 1 h at this temperature, then cooled to room temperature and poured on a mixture of 0.5 liter of cold water and 1 kg of ice. The crude product was extracted with 3x300 ml of dichloromethane. The combined organic extract was washed by aqueous K2CO3, dried over K2CO3, filtered through a short pad of silica gel 60 (40-63 µm), and then evaporated to dryness. The residue was purified by vacuum distillation to give 62.6 g (75 %) of 6-tert-butyl-5-methoxy-2-n-propylindan-1-one as a yellowish oil (bp 155-170^oC /4 mm Hg). ¹H NMR (CDCl₃): δ 7.67 (s, 1H), 6.87 (s, 1H), 3.93 (s, 3H), 3.23 (dd, J = 17.1 Hz, J = 7.6 Hz, 1H), 2.71 (dd, J = 17.1 Hz, J = 3.5 Hz, 1H), 2.66-2.60 (m, 1H), 1.94-1.88 (m, 1H), 1.51- 1.39 (m, 3H), 1.37 (s, 9H), 0.95 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl3): δ 207.76, 164.51, 154.70, 138.64, 129.18, 121.89, 107.70, 55.15, 47.41, 34.99, 33.83, 32.47, 29.53, 20.63, 14.05. 4-Bromo-6-tert-butyl-2-n-propyl-5-methoxyindan-1-one

Bromine (6.2 ml, 19.2 g, 120 mmol) was added dropwise by vigorous stirring over 15 min to a mixture of 31.3 g (0.120 mol) of 6-tert-butyl-2-n-propyl-5-methoxyindan-1-one, 39.45 g of sodium acetate, 1.0 g of ⁿBu₄NI, 100 ml of dichloromethane, and 200 ml of water at 5 °C. This mixture was stirred for 1 h at 5 °C, then a solution of 20 g of sodium acetate in 100 ml of water was added followed by addition of 3.1 ml (60 mmol) of bromine. The resulting mixture was additionally stirred for 1 h at this temperature and then washed by aqueous Na₂SO₃ to remove an excess of bromine. The crude product was extracted with 3x100 ml of dichloromethane. The combined organic extract was dried over K₂CO₃, filtered through a pad of silica gel 60 (40-63 µm) and evaporated to dryness. Crystallization of the residue from ca.50 ml of n-pentane at -15^oC gave 33.2 g of the title product (81.6%). ¹H NMR (CDCl₃): δ 7.69 (s, 1H), 4.03 (s, 3H), 3.22 (dd, J = 18.3 Hz, J = 8.4 Hz, 1H), 2.72- 2.65 (m, 2H), 1.97-1.88 (m, 1H), 1.54-1.43 (m, 3H), 1.40 (s, 9H), 0.97 (t, J = 7.3 Hz, 3H). ¹³C NMR (CDCl₃): δ 207.70, 162.75, 154.24, 145.43, 133.15, 121.38, 116.66, 61.64, 47.52, 35.66, 34.04, 33.64, 30.62, 20.59, 14.03. 6-tert-Butyl-2-n-propyl-5-methoxy-4-(3,5-dimethylphenyl)-indan-1-one

A mixture of 16.6 g (48.9 mmol) of 4-bromo-6-tert-butyl-2-n-propyl-5-methoxyindan-1-one, 9.45 g (63.0 mmol, 1.28 equiv.) of 3,5-Me₂C₆H₃B(OH)₂, 0.26 g (0.5 mmol, 1 mol.%) of Pd(P^tBu₃)₂, 15.8 g of Na₂CO₃, 80 ml of 2-methyltetrahydrofurane, and 75 ml of water was refluxed for 6 h. Further on, 100 ml of water was added, the organic layer was separated, and the aqueous layer was extracted with 2x50 ml of dichloromethane. The combined organic extract was dried over K₂CO₃ and then evaporated to dryness. The product was purified by flash-chromatography on silica gel 60 (40-63 um, eluent: dichloromethane- hexane = 2:1, vol.). The combined elute was evaporated to dryness, the residue was washed by 30 ml of n-pentane and dried in vacuum. This procedure gave 15.7 g (88.0%) of title product. ¹H NMR (CDCl3): δ 7.73 (s, 1H), 7.03 (s, 1H), 7.02 (s, 2H), 3.31 (s, 3H), 3.06 (dd, J = 17.3 Hz, J = 7.6 Hz, 1H), 2.58 (m, 1H), 2.49 (dd, J = 17.3 Hz, J = 3.8 Hz, 1H), 2.39 (s, 6H), 1.94-1.84 (m, 1H), 1.42 (s, 9H), 1.40-1.34 (m, 3H), 0.91 (t, J = 7.3 Hz, 3H). ¹³C NMR (CDCl3): δ 208.45, 163.41, 153.09, 143.21, 138.06, 136.28, 132.67, 131.33, 129.07, 127.17, 121.14, 60.48, 47.51, 35.33, 33.67, 32.20, 30.50, 21.37, 20.62, 14.02. 5-tert-Butyl-2-n-propyl-6-methoxy-7-(3,5-dimethylphenyl)-1H-indene

NaBH₄ (2.44 g, 64.6 mmol) was added to a solution of 6-tert-butyl-2-n-propyl-5-methoxy- 4-(3,5-dimethylphenyl)-indan-1-one (15.7 g, 43 mmol) in 180 ml of THF cooled to 5 °C. To this mixture, 70 ml of MeOH was added dropwise over ca.5 h at 5 °C, and the resulting mixture was stirred overnight at room temperature. Then, this mixture was evaporated to dryness, 200 ml of dichloromethane and 200 ml water were added to the residue, and the so obtained mixture was acidified with 2 M HCl to pH~6.5. The organic layer was separated, the aqueous layer was additionally extracted with 2x50 ml of dichloromethane. The combined organic extract was evaporated to dryness. TsOH (300 mg) was added to a solution of the residue in 300 ml of toluene. This mixture was refluxed with Dean-Stark head for 10 min and then cooled to room temperature using a water bath. The formed solution was washed with 10% Na₂CO₃, the organic layer was separated, the aqueous layer was extracted with 2x50 ml of dichloromethane. The combined organic extract was dried over K₂CO₃ and then evaporated to dryness. The product was purified by flash- chromatography on silica gel 60 (40-63 µm, eluent: dichloromethane-hexane = 1:1, vol.) and dried in vacuum to give 14.0 g (93.4%) of pure product as a mixture of two isomeric indenes. ¹H NMR (CDCl3): δ 7.34 (s), 7.23 (s), 7.10 (s), 7.09 (s), 6.98 (s), 6.45 (m), 6.34 (s), 3.30 (s), 3.25 (s), 3.12 (s), 2.38-2.34 (m), 1.55 (sextet, J = 7.4 Hz), 1.44 (s), 0.91 (t, J = 7.3 Hz). ¹³C NMR (CDCl3): δ 156.08, 154.24, 151.14, 149.97, 144.16, 141.56, 140.85, 140.44, 138.30, 137.87, 137.72, 137.65, 137.53, 137.43, 131.87, 128.46, 128.28, 127.84, 127.20, 126.05, 125.40, 120.81, 117.13, 60.65, 60.44, 41.13, 41.04, 35.12, 35.04, 33.52, 33.29, 31.11, 31.00, 22.44, 22.29, 21.42, 14.01, 13.94. [4,8-Bis(3,5-dimethylphenyl)-2-methyl-1,5,6,7-tetrahydro-s-indacen-1-yl][6-tert-butyl-4- (3,5-dimethylphenyl)-5-methoxy-2-propyl-1H-inden-1-yl]dimethylsilane

ⁿBuLi in hexanes (2.5 M, 3.17 ml, 7.92 mmol) was added in one portion to a suspension of 4,8-di(3,5-dimethylphenyl)-6-methyl-1,2,3,5-tetrahydro-s-indacene (3.0 g, 7.92 mmol) in a mixture of 40 ml of ether and 35 ml of THF cooled to -50 °C. The resulting mixture was stirred overnight at room temperature, then the so obtained light-orange solution with a large amount of orange precipitate was cooled to -50 °C, and 75 mg of CuCN was added. The obtained mixture was stirred for 0.5 h at -25 °C, then a solution of [6-tert-butyl-4-(3,5- dimethylphenyl)-2-propyl-5-methoxy-1H-inden-1-yl]chlorodimethylsilane (3.5 g, 7.93 mmol) in 50 ml of THF was added in one portion. This mixture was stirred overnight at room temperature, then filtered through a pad of silica gel 60 (40-63 µm), which was additionally washed by 2x50 ml of ether. The combined organic elute was evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 µm, 600 ml, eluent: hexanes: dichloromethane = 5:1, vol.). This procedure gave 4.7 g (76%, purity ca.98%) of the title product (as a ca.2:3 mixture of two stereoisomers) as a colorless glassy solid. Anti-dimethylsilanediyl[2-methyl-4,8-di(3,5-dimethylphenyl)-1,5,6,7-tetrahydro-s-indacen- 1-yl][2-propyl-4-(3,5-dimethylphenyl)-5-methoxy-6-tert-butyl-inden-1-yl] zirconium dichloride (MC-I2)

ⁿBuLi in hexanes (2.5 M, 4.8 ml, 12.0 mmol) was added in one portion to a solution of 4.7 g (6.0 mmol) of [4,8-bis(3,5-dimethylphenyl)-2-methyl-1,5,6,7-tetrahydro-s-indacen-1- yl][6-tert-butyl-4-(3,5-dimethylphenyl)-5-methoxy-2-propyl-1H-inden-1-yl]dimethylsilane in 50 ml of di-n-butyl ether t room temperature. This mixture was stirred overnight at room temperature, then the resulting red solution was cooled to 0^oC in an ice-bath, and 1.4 g (6.0 mmol) of ZrCl₄ was added. The reaction mixture was stirred for 24 h at room temperature to give an orange-red suspension. This mixture was evaporated to dryness. This solid was extracted with 50 ml of hot toluene. On the evidence of NMR spectroscopy, the obtained extract included a ca.4:1 mixture of anti- and syn-zirconocene dichlorides. This extract was evaporated to dryness, and 30 ml of hexane was added. The yellow precipitate fallen from the obtained solution at room temperature was collected and dried in vacuum. This procedure gave 3.1 g of anti-zirconocene dichloride contaminated with di- n-butyl ether which was further recrystallized from a mixture of ca.5 ml of toluene and 15 ml of hexane to give 1.45 g of yellow powder of anti-zirconocene dichloride containing 0.5 mol of toluene per mol of the complex, so the adjusted net weight of the isolated anti- complex was 1.38 g (24%). Anal. calc. for C₅₆H₆₄Cl₂OSiZr*0.5(C₇H₈): C, 72.23; H, 6.93. Found: C, 72.15; H, 7.21.¹H NMR (CDCl₃): δ 7.42 (s, 1H), 7.25 (very br. s, 4H), 7.14 (s, 1H), 7.03 (s, 1H), 6.99 (s, 1H), 6.96 (s, 1H), 6.94 (s, 1H), 6.81 (s, 1H), 6.59 (s, 1H), 3.39 (s, 3H), 3.13-3.03 (m, 2H), 2.97-2.90 (m, 1H), 2.57-2.43 (m, 2H), 2.41 (s, 3H), 2.37 (s, 3H), 2.34 (12H), 2.29 (s, 3H), 2.18-2.11 (m, 1H), 2.05-1.97 (m, 1H), 1.81-1.70 (m, 1H), 1.35 (s, 9H), 1.30-1.18 (m, 2H), 1.14 (s, 3H), 0.82 (t, J = 7.3 Hz, 3H), -0.13 (s, 3H). ¹³C NMR (CDCl3): δ 159.90, 144.63, 144.17, 143.25, 141.39, 139.87, 138.39, 138.06, 137.74 (br. s), 137.22, 136.84, 134.70, 134.44, 132.03, 131.99, 131.72, 130.56, 129.02, 128.81, 128.69, 127.90, 127.52, 126.91, 123.55, 123.38, 121.17, 120.33, 81.89, 81.61, 62.65, 35.68, 34.06, 33.94, 32.39, 30.40, 26.97, 26.04, 21.56, 21.47, 21.41, 21.25, 19.86, 13.87, 3.83, 2.31. Synthesis of MC-I3 Synthesis of the second indene pre-ligand: 4,8-Bis(3,5-dimethylphenyl)-6-ethyl-1,2,3,5- tetrahydro-s-indacene 2-Ethylacryloyl chloride

One drop of DMF was added to a solution of 77.1 g (0.77 mol) of 2-ethylacrylic acid in 600 ml of dichloromethane cooled in an ice bath. Then, to the resulting solution, 108 g (0.85 mol) of oxalyl chloride was added dropwise over 1 h, and the reaction mixture was stirred overnight at room temperature. The formed mixture was concentrated, and the residue was distilled in vacuum to give 65 g (71.2%) of 2-ethylacryloyl chloride as a colorless liquid, b.p.55-75^oC/100 mbar. ¹H NMR (CDCl₃): δ 6.55 (s, 1H), 6.02 (s, 1H), 2.39 (q, J = 7.4 Hz, 2H), 1.12 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl₃): δ 168.73, 146.60, 132.03, 25.33, 12.55. 4,8-Bis(3,5-dimethylphenyl)-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one, method A 2-Ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

A mixture of 65.0 g (548 mmol) of 2-ethylacryloyl chloride and 65.0 g (548 mmol) of indane was added dropwise over 15 min to a suspension of 182 g (1.37 mol) of AlCl3 in 1000 ml of dichloromethane cooled to 0 °C. The cooling bath was then removed, and this solution was stirred overnight at room temperature. The reaction mixture was poured onto 2 kg of crushed ice, the organic phase was separated, and the aqueous phase was extracted with 3x200 ml of dichloromethane. The combined organic extract was washed by aqueous K2CO3, dried over K2CO3, passed through a short pad of silica gel 60 (40-63 µm). The elute was evaporated to dryness. The formed oil was distilled under vacuum to give 80.92 g (ca.74%, purity ca.70%) of a slightly yellowish oil, b.p. 130-145^oC/3 mm Hg. The so obtained 2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one was used without further purification. ¹H NMR (CDCl3): δ 7.52 (s, 1H), 7.24 (s, 1H), 3.20 (dd, J¹ = 7.8 Hz, J² = 17.1 Hz, 1H), 2.94-2.86 (m, 4H), 2.71 (dd, J¹ = 3.6 Hz, J² = 17.0 Hz, 1H), 2.59-2.54 (m, 1H), 2.13-2.05 (m, 2H), 1.96-1.90 (m, 1H), 1.56-1.45 (m, 1H), 0.98 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl3): δ 208.05, 152.68, 152.60, 143.74, 135.46, 121.77, 118.67, 48.89, 32.79, 31.74, 25.52, 24.31, 11.30. 4,8-Dibromo-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

A solution of 80.9 g (ca.404 mmol) of 2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one (as prepared above, ca.70% purity) in 200 ml of dichloromethane was added dropwise over 15 min to a suspension of 134.7 g (1.01 mol, 2.5 equiv.) of AlCl3 in 400 ml of dichloromethane at –10 °C. The reaction mixture was stirred for 10 min at this temperature, then 41.7 ml (129.4 g, 809 mmol, 2.0 equiv.) of bromine was added dropwise over 1 h. The resulting mixture was stirred overnight at room temperature and then poured onto 1000 cm³ of crushed ice. The organic layer was separated, the aqueous layer was extracted with 3x300 ml of dichloromethane. The combined organic extract was washed with aqueous K₂CO₃, dried over K₂CO₃, passed through a short pad of silica gel 60 (40-63 µm), and the obtained elute was evaporated to dryness. The crude product was roughly purified by crystallization from 500 ml of n-hexane to give 89.5 g of crude product. The following crystallization of this crude product from 500 ml of n-hexane gave analytically pure product. The mother liquor from the last crystallization was evaporated to ca.200 ml to give a white suspension of the product in hexane. This suspension was heated to the boiling point (~65-70 °C) and then filtered (while hot) through glass frit (G3). The so obtained precipitate was dried under vacuum to give one more crop of the title product. The overall yield was 59.9 g (41%).¹H NMR (CDCl₃): δ 3.17-3.05 (m, 5H), 2.70-2.60 (m, 2H), 2.17 (quin, J = 7.7 Hz, 2H), 2.03-1.93 (m, 1H), 1.59-1.48 (m, 1H), 1.02 (t, J = 7.4 Hz, 3H).¹³C NMR (CDCl₃): δ 204.94, 154.85, 152.52, 146.90, 134.22, 117.80, 115.17, 49.83, 35.64, 34.60, 32.30, 24.53, 23.18, 11.47. 4,8-Bis(3,5-dimethylphenyl)-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

A mixture of 59.9 g (167 mmol) of 4,8-dibromo-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)- one, 56.4 g (376 mmol, 2.25 equiv.) of 3,5-dimethylphenylboronic acid, 1.34 g of Pd(P^tBu3)2, 95.8 g of Na2CO3, 600 ml of 2-methyltetrahydrofurane, and 420 ml of water was refluxed for 7 h. Then, 600 ml of water was added, the organic layer was separated, and the aqueous layer was extracted with 300 ml of dichloromethane. The combined organic extract was dried over K2CO3 and then evaporated to dryness to give a brown solid mass. The product was isolated by column chromatography on silica gel 60 (40-63 µm, d 50 mm, l 400 mm, eluent: hexanes-dichloromethane = 1:3, vol.). The elute was evaporated to dryness followed by trituration of the residue with 300 ml of n-hexane. The obtained suspension was filter through glass frit (G3), and thus obtained white precipitate was washed with 2x30 ml of n-hexane and then dried under vacuum. Yield 61.47 g (90%).¹H NMR (CDCl3): δ 7.03 (s, 1H), 6.99 (s, 1H), 6.95 (s, 2H), 6.92 (s, 2H), 3.08 (dd, J¹ = 8.7 Hz, J² = 18.0 Hz, 1H), 2.88-2.68 (m, 4H), 2.57-2.49(m, 2H), 2.39 (s, 6H), 2.36 (s, 6H), 2.04- 1.84 (m, 3H), 1.47-1.36 (m, 1H), 0.91 (t, J = 7.4 Hz, 3H). ¹³C NMR (CDCl₃): δ 207.37, 151.81, 149.90, 143.55, 138.22, 137.93, 137.23, 136.88, 135.89, 135.43, 132.40, 128.93, 126.74, 126.49, 49.72, 33.03, 31.96, 31.06, 25.64, 24.30, 21.46, 21.41, 11.66. 4,8-Bis(3,5-dimethylphenyl)-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one, method B 2-Ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

4.76 g (47.5 mmol, 1.27 equiv.) of 2-ethylacrylic acid was added to the Eaton's reagent obtained from 8.28 g of P₄O₁₀ and 52 ml of MeSO₃H at 50^oC. To this rapidly stirred mixture 4.43 g (37.5 mmol) of indane (~95% purity) was added dropwise for ca.45 min at 48-50^oC. The resulting mixture was stirred for 1 h at this temperature, then cooled to room temperature, and poured on a mixture of 0.4 liter of cold water and 0.1 kg of ice. The crude product was extracted with 3 x 50 ml of dichloromethane, and 75 ml of hexane was added. The combined organic extract was filtered through a pad of silica gel 60 (40-63 um, 20 ml), which was additionally washed by 2 x 40 ml of a 1:2 mixture of hexane and dichloromethane. The elute was evaporated to dryness. The crude product was dissolved in 100 ml of dichloromethane; the formed solution was washed by aqueous K2CO3, dried over K2CO3, and then evaporated to dryness to give 7.15 g (95%, ca.60% purity) of 2- ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one as a yellow oil. 4,8-Dibromo-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

A solution of 7.0 g (ca. 35 mmol) of 2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one (as prepared above, ca.60% purity) in 10 ml of dichloromethane was added dropwise over 15 min to a suspension of 11.6 g (87 mmol) of AlCl₃ in 40 ml of dichloromethane at –10 °C. The reaction mixture was stirred for 10 min at this temperature, then 4.0 ml (12.4 g, 77.5 mmol, 2.2 equiv.) of bromine was added dropwise over 1 h at –10 °C. The resulting mixture was stirred overnight at room temperature and then poured onto 100 cm³ of crushed ice. The organic layer was separated, the aqueous layer was extracted with 3x30 ml of dichloromethane. The combined organic extract was passed through a short pad of silica gel 60 (40-63 µm, 40 ml), the silica gel layer was additionally washed with 2x30 ml of dichloromethane, and the obtained elute was evaporated to dryness. The obtained oil was dissolved with 50 ml of hexane. After 5 min, a black precipitate formed was filtered off. Crystallization of the filtrate at –15 °C overnight gave 6.4 g of crude solid product. This crude product was dissolved in a mixture of 25 ml of n-hexane and 6 ml toluene at reflux. The following crystallization (from the boiling point to RT) gave 4 g of the desired product slightly contaminated with polymeric by-products. The mother liquor from the last crystallization was evaporated to dryness. Crystallization of the residue from a mixture of 10 ml of hexane and 1 ml of toluene gave one more crop (0.9 g) of the product. Thus obtained 4.9 g of the solid product was dissolved in 20 ml of a 1:1 mixture of hexane and dichloromethane, and this solution was passed through a short pad of silica gel 60 (40-63 µm, 15 ml). The silica gel layer was additionally washed with 2x20 ml of a 1:1 mixture of hexane and dichloromethane. The combined elute was evaporated to dryness to give 4.6 g (37%) of the title product as a yellowish solid. 4,8-Bis(3,5-dimethylphenyl)-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one

A mixture of 4.3 g (12 mmol) of 4,8-dibromo-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)- one, 4.14 g (27.6 mmol, 2.3 equiv.) of 3,5-dimethylphenylboronic acid, 0.1 g of Pd(P^tBu3)2, 6.9 g of Na2CO3, 43 ml of 2-methyltetrahydrofurane, and 30 ml of water was refluxed for 7 h. Then, 50 ml of dichloromethane was added, the organic layer was separated, and the aqueous layer was extracted with 2x30 ml of dichloromethane. The combined organic extract was dried over K2CO3 and then evaporated to dryness. The solid mass was dissolved in 30 ml of a 2:3 mixture of hexane and dichloromethane, and the formed solution was passed through a short pad of silica gel 60 (40-63 µm, 20 ml). The silica gel layer was washed with 3x20 ml of a 1:1 mixture of hexane and dichloromethane, and the obtained elute was evaporated to dryness. The solid residue was treated with 20 ml of pentane, the formed suspension was filtered through glass frit (G3), the precipitate was dried in vacuum to give 3.8 g of the title product. The mother filtrate was evaporated to ca.10 ml. to form a suspension that was filtered through glass frit (G3). The residue was dried under vacuum to give one more crop (0.95 g) of the title product. The overall yield 4.75 g (97%, purity 98%). 4,8-Bis(3,5-dimethylphenyl)-6-ethyl-1,2,3,5-tetrahydro-s-indacene

Methanol (100 ml) was added dropwise over 5 h to a mixture of 20.0 g (49 mmol) of 4,8- bis(3,5-dimethylphenyl)-2-ethyl-3,5,6,7-tetrahydro-s-indacen-1(2H)-one and 4.28 g (109 mmol) of NaBH4 in 300 ml of THF at 0-5 °C. The obtained mixture was stirred overnight at room temperature and then evaporated to dryness.400 ml of dichloromethane and 1000 ml of water were added to the residue, and the so obtained mixture was acidified by 2 M HCl to pH~6.5. The organic layer was separated, the aqueous layer was additionally extracted with 2x200 ml of dichloromethane. The combined organic extract was dried over Na2SO4 and evaporated to dryness to give a white solid mass. TsOH (1.0 g) was added to a solution of this solid mass in 350 ml of toluene, preheated to ca.60 °C. This mixture was refluxed with Dean-Stark head for 12 min. Then, the reaction mixture was quickly cooled to room temperature using an ice-water bath. The formed solution was washed with 10% Na2CO3, the organic layer was separated, the aqueous layer was extracted with 100 ml of dichloromethane. The combined organic extract was dried over K2CO3 and then evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 µm, d 50 mm, l 30 mm, hexanes-dichloromethane = 10:1, vol). This procedure gave 19.4 g (100%) of the title product as a white solid.¹H NMR (CDCl3): δ 7.05 (s, 2H), 7.03 (s, 2H), 6.98 (s, 2H), 6.44 (m, 1H), 3.25 (s, 2H), 2.89 (t, J =7.3 Hz, 2H), 2.83 (t, J =7.3 Hz, 2H), 2.42-2.33 (m, 14H), 1.98 (quin, J =7.3 Hz, 2H), 1.10 (t, J =7.4 Hz, 3H). ¹³C NMR (CDCl3): δ 151.79, 142.60, 140.88, 140.24, 140.19, 139.83, 138.42, 137.55, 137.39, 133.53, 129.79, 128.39, 128.18, 127.32, 126.60, 124.41, 40.59, 32.78, 32.51, 26.09, 24.45, 21.42, 13.44. [4,8-Bis(3,5-dimethylphenyl)-2-ethyl-1,5,6,7-tetrahydro-s-indacen-1-yl][6-tert-butyl-4- (3,5-dimethylphenyl)-2-ethyl-5-methoxy-1H-inden-1-yl]dimethylsilane

ⁿBuLi in hexanes (2.5 M, 3.84 ml, 9.6 mmol) was added in one portion to a solution of 4,8- bis(3,5-dimethylphenyl)-6-ethyl-1,2,3,5-tetrahydro-s-indacene (3.77 g, 9.6 mmol) in a mixture of 40 ml of ether and 40 ml of THF at -50 °C. This mixture was stirred overnight at room temperature, then the resulting greenish-yellow suspension was cooled to -50 °C, and 100 mg of CuCN was added. The obtained mixture was stirred for 0.5 h at -20 °C, then a solution of 4.1 g (9.6 mmol) of [6-tert-butyl-4-(3,5-dimethylphenyl)-2-ethyl-5- methoxy-1H-inden-1-yl](chloro)dime-thylsilane in 50 ml of THF was added in one portion. The formed mixture was stirred for 12 h at room temperature, then filtered through a pad of silica gel 60 (40-63 um) which was additionally washed by 2x50 ml of ether. The combined organic elute was evaporated to dryness. The crude product was purified by flash chromatography on silica gel 60 (40-63 µm, 600 ml, eluent: hexanes: dichloromethane = 5:1, vol.). This procedure gave 5.10 g (6.5 mmol, yield ca.67.8%, purity ca.98%) of the title product (as a ca 40:60 mixture of the stereoisomers) as a glassy solid.

Anti-dimethylsilanediyl[η⁵-4,8-bis(3,5-dimethylphenyl)-2-ethyl-1,5,6,7-tetrahydro-s- indacen-1-yl][η⁵-6-tert-butyl-4-(3,5-dimethylphenyl)-2-ethyl-5-methoxyinden-1-yl] zirconium dichloride (MC-I3)

ⁿBuLi in hexanes (2.5 M, 5.1 ml, 12.75 mmol) was added in one portion to a solution of [4,8-bis(3,5-dimethylphenyl)-2-ethyl-1,5,6,7-tetrahydro-s-indacen-1-yl][6-tert-butyl-4-(3,5- dimethylphenyl)-2-ethyl-5-methoxy-1H-inden-1-yl]dimethylsilane (5.00 g, 6.38 mmol) in 50 ml of di-n-butyl ether at room temperature. This mixture was stirred for 5 h at room temperature, then the resulting solution was cooled to 0 °C in an ice bath, and ZrCl4 (1.49 g, 6.39 mmol) was added. The formed mixture was stirred for 24 h at room temperature to give a yellow suspension. This suspension was evaporated to dryness, and the residue was extracted with 50 ml of warm toluene. The precipitate was filtered off (G4). On the evidence of NMR spectroscopy, the resulting filtrate included a ca.95/5 mixture of anti- and syn-zirconocene dichlorides. This filtrate was evaporated to dryness, and 30 ml of hexane was added. The orange precipitate fallen from this solution overnight at room temperature was filtered off (G3), washed with 10 ml of n-hexane, and then dried in vacuum. This procedure gave 4.8 g of anti-zirconocene dichloride (contaminated with ca. 0.6% of syn-isomer) containing ca. 0.02 mol of ether per mol of Zr and 0.08 mol of n- hexane per mol of Zr, so the adjusted net weight of the isolated complex was ca.4.75 g (yield ca.79%). Anal. calc. for C₅₆H₆₄Cl₂OSiZr.: C, 71.30; H, 6.84. Found: C, 71.45; H, 7.02. ¹H NMR (CDCl₃): δ 7.65-6.7 (very br.s, 4H), 7.38 (s, 1H), 7.09 (s, 1H), 7.02 (s, 1H), 6.99 (s, 1H), 6.96 (s, 1H), 6.95 (s, 1H), 6.86 (s, 1H), 6.60 (s, 1H), 3.40 (s, 3H), 3.11-2.86 (m, 4H), 2.60- 2.25 (m, 22H), 1.99 (m, 1H), 1.82-1.70 (m, 1H), 1.35 (s, 9H), 1.14-1.10 (m, 6H), 0.90 (t, J = 7.4 Hz, 3H), -0.16 (s, 3H).¹³C NMR (CDCl3): δ 159.82, 144.81, 144.09, 143.11, 141.75, 141.49, 141.12, 138.40, 138.16, 137.77 (br.s), 137.38, 136.92, 134.52, 132.25, 132.12, 131.74, 130.93, 128.96, 128.85, 128.79, 128.70, 127.89, 127.50 (br.s), 126.85, 122.95, 121.18, 120.77, 119.34, 81.54, 80.54, 62.68, 35.63, 33.91, 32.38, 30.39, 26.52, 26.07, 25.86, 21.46, 21.41, 21.27, 17.00, 16.59, 4.20, 2.38. Catalyst synthesis, used chemicals MAO Axion CA133030 wt-% solution in toluene was purchased from Chemtura/Lanxess and used as received and stored at –20°C for not longer than 6 months. All the chemicals and chemical reactions were handled under an inert gas atmosphere using Schlenk and glovebox techniques, with oven-dried glassware, syringes, needles or cannulas. All catalysts have been prepared using silica Sunspera AGC DM-L-303, calcined at 600 °C. Catalyst preparations The catalysts were prepared by following a two-step preparation method. First step was the preparation of SiO2/MAO (activated carrier), followed by a second step where a toluene solution of the metallocene complex was impregnated on the dry support from the first step. Only in case the metallocene was not enough soluble in toluene, a second aliquot of MAO was added to the metallocene/toluene slurry in order to promote the full dissolution of the metallocene. Preparation of SiO2/MAO activated carrier A steel reactor equipped with a mechanical stirrer and a filter net was flushed with nitrogen. 10 kg of SiO2 carrier was first added from a feeding drum into the reactor, followed by careful pressurizing and depressurizing with nitrogen. Then, toluene (43.5 kg) was added. The SiO2/toluene slurry was stirred for 25 min at 22 °C. Then, 18 kg of 30 wt% MAO in toluene (Axion CA 1330) was added slowly (140 min) through a 12 mm line on the top of the reactor keeping the temperature around 22 °C. After MAO addition, the reactor temperature was quickly increased to 90 °C and the mixture was stirred at this temperature for 120 min. Then the hot toluene was filtered out and the solid cake was washed twice with hot toluene while stirring (43.5 kg, 90 °C, 30 min, 40 rpm). Each time the hot toluene was filtered out. Finally the solid cake was dried with slow stirring (5 rpm) under vacuum for 9 h at 80 °C. Synthesis of SiO2/MAO/MC-C1 = Comparison catalyst 1 (CC1) In a nitrogen filled glovebox, dry toluene (2.1 mL) was added to 41.9 mg of metallocene MC-C1 in a septum bottle. The mixture was stirred for 30 minutes at room temperature. Next, 2.0 g of the silica/MAO carrier was placed in a glass vial. The solution of metallocene in toluene was added dropwise by means of a syringe to the SiO2/MAO carrier over the course of 5 minutes with gentle mixing. The resulting mixture was shaken well and allowed to stay for 1 hour. The resulting solid was dried under vacuum for 1 hour at 60 °C to yield the catalyst as red free flowing powder Synthesis of SiO2/MAO/MC-C2 = Comparison catalyst 2 (CC2) In a nitrogen filled glovebox, dry toluene (2.5 mL) was added to 29.0 mg of metallocene MC-C2 in a septum bottle. The solution was stirred for 30 minutes at room temperature. Next, 2.000 g of SiO2/MAO was placed in a septum bottle. The solution of metallocene in toluene was added dropwise by means of a syringe to the SiO2/MAO carrier over the course of 5 minutes with gentle mixing. The resulting powder was allowed to rest for 1 hour, then it was transferred into a Schlenk flask and dried under vacuum for 1 hour at 60 °C to yield the catalyst as a light red free-flowing powder. Synthesis of SiO2/MAO/MC-I1 = Inventive catalyst 1 (IC1) In a nitrogen filled glovebox, dry toluene (5 mL) was added to 60.2 mg of metallocene MC- I1 in a septum bottle. The solution was stirred for 30 minutes at room temperature. Next, 0.2 mL of a 30 wt% solution of methylalumoxane (MAO) in toluene (Axion CA1330) was added and the solution stirred for additional 30 min. Then, the solution of metallocene and MAO in toluene was added dropwise by means of a syringe to 4.003 g of SiO2/MAO in a septum bottle carrier over the course of 10 minutes with gentle mixing. The resulting powder was allowed to rest for 1 hour, then it was transferred into a Schlenk flask and dried under vacuum for 1 hour and 45 min at 60 °C to yield the catalyst as a light red free- flowing powder. Synthesis of SiO2/MAO/ MC-I2 = Inventive catalyst 2 (IC2) In a nitrogen filled glovebox, dry toluene (2.5 mL) was added to 28.4 mg of metallocene MC-I2 in a septum bottle. The solution was stirred for 30 minutes at room temperature. Next, 2.000 g of SiO2/MAO was placed in a septum bottle. The solution of metallocene in toluene was added dropwise by means of a syringe to the SiO2/MAO carrier over the course of 5 minutes with gentle mixing. The resulting powder was allowed to rest for 1 hour, then it was transferred into a Schlenk flask and dried under vacuum for 1 hour at 60 °C to yield the catalyst as a red free-flowing powder. Synthesis of SiO2/MAO/ MC-I3 = Inventive catalyst 3 (IC3) In a nitrogen filled glovebox, dry toluene (2.5 mL) was added to 28.4 mg of metallocene MC-I3 in a septum bottle. The solution was stirred for 30 minutes at room temperature. Next, 2.000 g of SiO₂/MAO was placed in a septum bottle. The solution of metallocene in toluene was added dropwise by means of a syringe to the SiO₂/MAO carrier over the course of 5 minutes with gentle mixing. The resulting powder was allowed to rest for 1 hour, then it was transferred into a Schlenk flask and dried under vacuum for 1 hour at 60 °C to yield the catalyst as a light red free-flowing powder. The metallocene content in each catalyst is calculated from mass balance. The values are listed in Table 1: Table 1: catalysts tested and their metallocene content Metallocene Catalyst Al MC in catalyst * # wt% wt% MC-C1 CC1 13.2 1.56 MC-C2 CC2 13.8 1.43 MC-I1 IC1 12.0 1.46 MC-I2 IC2 12.3 1.40 MC-I3 IC3 12.6 1.36 * MC=metallocene; metallocene content in the dry catalyst calculated from mass balance Polymerization examples Monomers and gases Hydrogen (quality 6.0) was supplied by Air Liquide and used as received. Propylene, quality 2.3, butene and ethylene have been purified by passing through columns filled with PolyMax301 T-4427B (60°C; Cu/CuO), Molecular sieve MS13X-APG 1/16 and Selexsorb COS 1/8. Propylene/butene/ethylene terpolymerization procedure (20-L reactor, liquid monomers) Polymerization in liquid monomers A stainless-steel reactor equipped with a ribbon stirrer, and a total volume of 21.2 dm³ containing 0.2 bar-g propylene, was filled with additional 4.45 kg propylene from a balance. Triethylaluminium (0.8 ml of 0.62 molar solution in n-heptane) was added using a stream of 250 g propylene. Then the chosen amount of H2 was added via mass flow controller in one minute. The reactor temperature was stabilized at the desired temperature of the prepolymerization step by using a HB-Thermostat. The solution was stirred at 250 rpm for at least 20 min. Then the catalyst was injected as described in the following. The desired amount of catalyst (solid or as oil slurry) was loaded into a stainless steel vial in a glovebox. Then the catalyst vial was mounted on a port on the lid of the reactor. The catalyst was fed into the reactor by flushing 250 g propylene from the balance through the catalyst vial. Stirring speed was kept at 250 rpm and pre-polymerization was run for the set time and temperature. Then the polymerization temperature was increased to the target value. At a defined temperature, ethylene, butene and a second aliquot of H2 (if needed) are added in~ 1-2 min by using MFCs. Afterwards the reactor temperature was kept constant throughout the polymerization. The polymerization time was measured starting when the temperature was 2 °C below the set polymerization temperature. When the set time has lapsed, the reaction was stopped by injecting 5 ml ethanol, cooling the reactor and simultaneously flashing the volatile components. After purging the reactor 3 times with N2 and one vacuum/N2 cycle, the reactor was opened; the polymer powder was taken out and dried overnight in a fume hood.100 g of the polymer was additivated with 0.5 wt% Irganox B225 (dissolved in acetone) and then dried overnight in a fume hood and additionally one hour in a vacuum drying oven at 60°C. Polymerization in gas phase After the bulk step was completed, the stirrer speed was reduced to 50 rpm and the pressure was reduced to 0.4 bar-g by venting the monomers. Then the stirrer speed was set to 180 rpm, the reactor temperature to 70 °C and a given batch amount of ethylene was added to reach the desired comonomer ratio and pressure of 21 bar-g by feeding a C3/C2 gas mixture of composition defined by:

C2/C3 is the weight ratio of the two monomers and R is their reactivity ratio, determined experimentally. In the present experiments, R=0.4. When the pressure reached 20 °C bar-g, hydrogen was added via flow controller in 1 minute. The temperature was held constant by thermostat and the pressure of 21 bar-g was kept constant by feeding via mass flow controller a C2/C3 and C4/C3 gas mixture of composition corresponding to the target polymer composition, until the set duration for this step has lapsed. Then the reactor was cooled down to about 30°C and the volatile components flashed out. After purging the reactor 2 times with N2 and one vacuum/N2 cycle, the product was taken out and dried overnight in a fume hood.100 g of the polymer was additivated with 0.5 wt% Irganox B225 (solution in acetone) and dried overnight in a fume hood, followed by one hour in a vacuum drying oven at 60°C. Polymerization results We have discovered that polymerization processes according to the invention, IE1 to IE8, that employ catalysts, IC1 to IC3, can produce terpolymers with improved MFR/productivity balance compared to comparative processes, CE1 to CE6, that employ comparative catalysts, CC1 and CC2. The polymerization results are listed in Tables 2 and 3 (polymerizations in liquid monomers) and in Tables 4 and 5 (2-step polymerizations in liquid monomers and in gas phase). As can be seen from Tables 2 to 5, processes according to the inventive examples produce terpolymers having relatively high molecular weights/low MFR2 at relatively high rates of catalyst productivity. Although CE1 and CE2 have catalyst productivities of 13.8 and 15.0 kg/gcat, respectively, the molecular weights of the terpolymers produced are relatively low/MFR2, relatively high. Similarly, although CE4 and CE5 provide terpolymers with higher molecular weights/lower MFR2, this is at the expense of productivity. The processes according to the inventive examples, IE1 to IE8, provide an improved balance of MFR2 and productivity.

C C C C C CE E E E E E ^I _E ^I _E ^I _E ^I _E ^I _E ^I _E ^I _E 654321 7654321 Example

^. C C C C C CCCCCCC ^I _C ^I _C ^I _C ^I _C ^I _C ^I _C ^I _C 21 1 1 1 321 1 1 1 1 Catalyst 8 6 6 64 4 5 5 5 Catalyst amount5₄3 60 30 39 69 26 ,₀4 5 44 4 ^{, , , , , , ,} ₀8 ,₀2 ,₀7 ,₀9 ,₀7 ,₀

1 ^, 0 ,₉0 ,₉0 ,₉0 ,₇0 ,₇0 ,₇0 , 0 , 0 , 0 , 0 , 0 , M MC content in dosed

2944776₇6₈5₇6₆7₇2₆9 g pure catalyst 30303030303030303030303030 °C Temperature of

prepolymerization step 1010101010101010101010101 m 0 Duration of the prepolymerization step

0 ^, ₅0 ,₆0 ,₅0 ,₇0 ,₇0 ,₇0 0 0 0 5 ^, ₆0 ^, 0 ^, 0 ^, 0 0 ^, 0 5 ^, 0 5 ^, N H2 fed before00055 _{6 6 5 7 7 7}5 L prepolymerization 552 525255 5 5 65 5 2 525252 g 8333 ^, ₄ ^, ₄ ^, ₄333 ^, ₄ ^, ₄ ^, ₄ ^, ₄ C2 fed in transition 262626262626262622 56 2 22 4554445 564646464 g C4 fed in transition 1 1 1 1 Duration of transition 5555 141314141414141313 from prepolymerization to bulk 70707075706570707070757065 °C Temperature of polymerization step 6 6 6 6 66 6 6 6 6 6 m 00000000000 6660 _n ⁱ Duration of the polymerization step C C C C C C TE E E E E E ^I _E ^I 6 5 4 3 2 1 7 _E ^I 6 _E ^I 5 _E ^{I I I} a 4 _E 3 _E 2 _E 1 b Example ^l _e 6 6 5 7 1 1 1 ₃26 90 58 7 7 4 4 6 4 8 2 8 2 1 0 95 81 9 0 1 ^. _P 0 0 9 9 48 28 0 g 6 yield o l_y 1 1 1 m 7 9 1 2 1 1 1 2 2 2 ^, ₃ 0 ^, ₃ 2 5 3 1 4 6 5 5 8 0 2 1 0 3 5 c g kg e ,₈ ^, ₈ ^, ₀ ^, ₉ ^, ₆ ^, ₈ ^{, , , , ,} at / ^r _iz Catalyst productivity a t 5 1 1 1 1 1 k i 1 _on 1 69 59 82 9 8 5 0 1 0 3 4 16 g s3 5 4 3 61 90 89 58 32 79 81 37 12 M^/ _g C Metallocene productivity i_n l_iq 0 0 0 0 0 u ^, ₃0 ^, ₄8 ^, ₄9 ^, ₄8 ^, ₄ 0 9 ^, ₄ 0 8 ^, ₄ 0 9 ^, ₄ 0 0 9 ^, ₅ ^, ₄ 0 0 ^, ₄ 0 7 ^, ₄ 0 8 ^, ₅ g 0 ^/ _m l bulk density, poured ⁱ _{d m} g o 1 1 1 1 ^/ ₁ n 9 ^, ₁ 2 ,₉ 0 ,₀ 6 2 ,₉ 0 2 ,₁ 1 3 ,₉ ^, ₆ 9 ,₆ 5 ,₀ 4 ,₀ 8 ,₃ 9 ,₀ 9 ,₅ 0 o m m n MFR2 powder i e r_s 0 ^, ₅ 0 ,₂ 0 ,₄ 0 ,₂ 0 ,₃ 0 ,₃ 0 ,₁ 0 ,₄ 0 ,₂ 0 ,₈ 0 ,₅ 0 ,₅ 0 w ^{: ,} ₁ ^t _{r % e} XS (24h-25°C) su lt 9 9 9 9 9 9 9 9 _s 3 ₂ 2 6 3 9 9 9 9 9 ° T ^{, , ,} ₈ 1 ,₄ 2 ,₂ 3 ,₆ 5 ,₈ 4 ,₁ 5 ,₁ 3 ,₆ 3 ,₉ 4 ,₂ 5 ,₆ C c 7 J 7 77 75 77 75 75 79 78 76 74 76 75 76 ^/ _g H c 12 1 1 1 1 1 1 1 1 1 1 9 28 2 2 2 2 3 3 3 3 3 13 13 °C T ^, ₆ ^, ₆ 9 ,₀ 8 ,₁ 8 ,₆ 9 ,₇ 2 ,₀ 0 ,₂ 0 ,₅ 0 ,₇ 0 ,₁ 0 ,₉ 1 ,₀ m H 6 8 8 7 77 77 78 8 J 91 0 7 1 87 79 77 79 78 80 ^/ _g m 11 1 1 1 1 1 1 1 3 10 11 11 13 14 16 0 1 5 1 1 3 1 1 4 1 1 4 1 1 5 1 ° 8 C SIT* from DSC 17 1 7 9 2 1 1 1 2 1 2 2 2 2 2 g 0 09 71 66 61 60 99 3 6 1 0 0 M5 5 0 5 5 0 0 5 70 35 00 90 40 ^/ _m0 0 0 0 00 00 00 0 o w0 0 0 0 0 00 00 00 00 00 l M 2 2 2 2 2 2 2 2 2 2 2 2 2 2 w ^. ₀ ^, ₂ ^, ₃ ^{, , , , , ,} ₂ 2 ,₃ 2 ,₂ 2 ,₂ 2 ,₂ ^/ _M n 1 ^, ₅ 1 2 ^, ₁ 1 8 ^, ₁ 1 8 ^, ₁ 1 7 ^, ₂ 1 2 ^, ₁ 1 1 ^, ₁ 1 0 ^, ₁ 1 2 ^, ₀ 1 9 ^, ₁ 1 6 ^, ₂ 1 1 ^, ₁ 1 5 ^, ₀ w 8 ^t _% C2 (NMR) 2 1 1 1 m ^, ₃0 ^, ₇8 ^, ₇9 ^, ₇ 1 7 ^, ₈ 1 5 ^, ₆ 1 7 ^, ₆ 1 6 ^, ₆ 1 9 ^, ₆ 1 4 ^, ₇ 1 5 ^, ₈ 1 3 ^, ₇ 1 4 ^, ₆ o 4 _% ^l C2 (NMR) 4 ^, ₉ 5 9 ^, ₂ 5 3 ^, ₁ 5 8 ^, ₂ 5 1 ^, ₂ 5 5 5 ^, ₂ ^, ₂ 5 0 ^, ₂ 5 5 ^, ₂ 5 5 5 5 w 9 ^, ₁7 ^, ₂8 ^, ₃4 ^, ₁8 ^t _% C4 (NMR) 3 m ^, ₇ 3 ,₉ 3 ,₉ 3 ,₉ 3 ,₉ 3 ,₉ 3 ,₉ 3 ,₉ 4 ,₀ 3 ,₉ 3 ,₉ 4 ,₀ 3 ,₉ o6 5 2 4 7 3 3 7 0 1 9 4 1 _% ^l C4 (NMR) 0 ^, ₇ 0 9 ^, ₈ 0 3 ^, ₈ 0 3 ^, ₈ 0 3 ^, ₈ 0 0 0 0 0 0 0 0 4 ^, ₈4 ^, ₈1 ^, ₈4 ^, ₈4 ^, ₈2 ^, ₈3 ^, ₈4 ^, ₈3 R(C4/C3)-NMR 0 ^, ₀ 0 ,₆ 0 ,₅ 0 ,₅ 0 ,₅ 0 ,₆ 0 ,₄ 0 , 0 , 0 , 0 , 0 , 0 , % 5 1 8 8 6 2 3 ₅3 ₄8 ₄8 ₄7 ₅4 ₅3 2,1e 0 ^, ₀ 0 3 ^, ₁ 0 6 ^, ₁ 0 0 0 0 0 0 0 0 0 0 % 4 ^, ₁5 ^, ₁6 ^, ₁4 ^, ₀8 ^, ₁2 ^, ₁3 ^, ₁0 ^, ₁2 ^, ₁1 ^, ₁0 E2,1 ^I _E T 8 Example a ^I b _C ^l _e 3 catalyst 5 ₄ 5 m ^{. ,} ₅ g _P Catalyst amount o P ^l _y r m 3 e 0 ° e C p temperature o ^r _iz s^l _y a m ^ti 1 m ^t _ee _on 0 p nⁱ duration rⁱ _z s a i 0 ^t _n ^, ₅ N L H2 fed i_o ^l _i0 n _q before prepoly u 1 m ⁱ _d 4 _n ⁱ Duration of transition _m from prepo o 5 ly to bulk n 2 ^, ₄ g o C2 fed i m4 n transition e 30 °C ^r _s g starting T of C2 feed ^t _ra _a 1 n n 6 ^/ _m C2 feed rate in s d n^{i i} 2 transition ^t _{i g o} a 6 n s 4 g ^, ₂ C4 fed in transition _pha 3 °C s0 e g start T of C4 feed ^: 80 ^/ _{m c} C4 feed rate in o nⁱ n transit d 70 ° ion C Temperature s B ^it _io4 m ^t _eu n0 _n ⁱ p s 70 duration ^l _k 0 b ^, ₄ a r-_g pressure flashed down from bulk to T m r 2 a 1 _n ⁱ _Time- ^g _t ^a _ra ^s _n ^p _s ^h _it ^a _io ^s _n ^e _Bulk- ns 7 GP. ⁱ 3 ^t _io 0 g C n ^, ₇ 3 fed transition 7 (MFC) ^f _ro 5 m 6 ^, ₃ g C2 fed _b 8 u 0 transition(MFC) ^l _k ^, ₃ N t01 L _o H2 added in GP _g ° a C s 20 ^/ _b T and P at which H2 _p a h r is added in GP a N s 3 mm e 00 _n ⁱ L/ H2-dosing rate 70 °C 2 b Temperature 1 a r-_g Pressure G 1 a 2 m s 0 _n ⁱ Duration _p 1 h 6 a 1 g ^f _e C s ^, ₄ d 3 e s 4 ^, ₆ g ^f _e C ^t _e d 2 p 10 ^{f ,} _e C ₃ g d 4 T ^I _E a 8 Example b l_{e 5} 9 ^. 6 _P 2 g yield total o l_ym e 1 ^r 7 ^, ₃ c g k i_z a g a t / ^ti_o Overall productivity ns k i 1 _n 2 g 7 ^/ metallocene overall ^l _iq 5 M_g C productivity u i_{d m} 8 w on 2 ^t _% split bulk om e 1 w ^r _s 8 ^t _% split gas phase _and 0 ₄ g _g ^, 9 ^/ _m a l bulk density, poured s p h g a 3 ^/ ₁ s ^, ₉ 0 e m MFR2 ^: nⁱ _resu 0 w ^lt_s ^, ₂ ^t _% XS (24h-25°C) 71 5 w ^, ₉ ^t _% C4 1 w ^, ₃ ^t _% C2 92 ° T ^, ₄ C c 7 J 6 ^/ _g H c 129 ° T ^, C ₇ m 7 J H 8 ^/ _g m 10 ° 8 C SIT* from DSC

Claims

CLAIMS 1. A process for producing a propylene copolymer resin, comprising polymerizing propylene and at least one comonomer selected from ethylene and C₄-C₁₀ alpha olefin comonomers; wherein the process is carried out in presence of a polymerization catalyst comprising, (i) a metallocene complex of formula (I); (ii) a cocatalyst system comprising a cocatalyst comprising a group 13 element; and (iii) optionally a support. wherein the metallocene complex of formula (I) is

wherein Mt is Zr or Hf; X is a sigma ligand; R¹ are each independently, same or different from each other, C1-C20 hydrocarbyl optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or, form together with the Si atom they are attached to, a C4-C8 ring; R² and R²’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H, linear or branched C1-C6-alkyl, C3-C8-cycloalkyl, or a C6-C9-aryl, provided that R² and R²’ are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C1-C6-alkyl, C7-C20-arylalkyl, C7-C20-alkylaryl, C6-C20 aryl, or -OR³¹, with R³¹ being C1-C10-hydrocarbyl, whereby at least one R³ per phenyl group and at least one R⁴ is not H; R⁵ and R⁶ are each independently, same or different from each other, C₁-C₁₀ hydrocarbyl, or may form, together with the C atoms they are attached to, a C₅-C₇ carbocycle; R⁵¹’ is C₁-C₁₀-hydrocarbyl; and R⁶’ is C(R⁶¹)₃, with R⁶¹ being linear or branched C₁-C₆-alkyl. 2. A process as claimed in claim 1, which a process for producing a propylene terpolymer resin, comprising polymerizing propylene and at least two different comonomers selected from ethylene and C₄-C₁₀ alpha olefin comonomers; preferably comprising polymerizing propylene, ethylene and a comonomer selected from C₄-C₁₀ alpha olefin comonomer; more preferably comprising polymerising propylene ethylene and butene. 3. A process as claimed in any one of the preceding claims, wherein the metallocene complex of formula (I) has formula (I-a)

(I-a) wherein Mt is Zr or Hf; X is a sigma ligand; n is 1 to 3, such as 1, 2 or 3, preferably 1; R¹ are each independently, same or different from each other, C₁-C₂₀ hydrocarbyl, optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or form together with the Si atom they are attached to a C₄-C₈-ring; R² and R²’ are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H, linear or branched C₁-C₆-alkyl, C_3-C₈-cycloalkyl, or a C_6-C₉-aryl, provided that R² and R²’ are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, C_7-20-arylalkyl, C_7-20-alkylaryl, C_6-20 aryl, or -OR³¹, with R³¹ being C₁-C₁₀-hydrocarbyl_, whereby at least one R³ per phenyl group and at least one R⁴ is not H; R⁵¹’ is C₁-C₁₀-hydrocarbyl; and R⁶’ is C(R⁶¹)₃, with R⁶¹ being linear or branched C₁-C₆-alkyl. 4. A process as claimed in any one of the preceding claims, wherein the metallocene complex of formula (I) has formula (I-b)

wherein Mt is Zr or Hf; X is a sigma ligand; R¹ are each independently, same or different from each other, C₁-C₂₀ hydrocarbyl, optionally containing up to two heteroatoms of Group 14-16 of the Periodic Table, or form together with the Si atom they are attached to a C₄-C₈-ring; R² and R²’ are each independently, same or different from each other, CH₂-R²¹, with R²¹ being H or linear or branched C₁-C₆-alkyl, provided that R² and R²’ are not both methyl; R³ and R⁴ are each independently, same or different from each other, H, linear or branched C₁-C₆-alkyl, C_7-20-arylalkyl, C_7-20-alkylaryl, C_6-20 aryl, or -OR³¹, with R³¹ being C₁-C₁₀-hydrocarbyl_, whereby at least one R³ per phenyl group and at least one R⁴ is not H. 5. A process as claimed in any one of the preceding claims, wherein one or two R³ per phenyl group are not H and, on both phenyl groups, the R³ are the same, and two R⁴ on the phenyl group are not H and these two R⁴ are the same_; or, wherein two R³ per phenyl group are not H and, on both phenyl groups, the R³ are linear or branched C₁-C₆-alkyl, preferably methyl, and two R⁴ on the phenyl group are not H and these two R⁴ are linear or branched C₁-C₆ alkyl, preferably methyl. 6. A process as claimed in any one of the preceding claims, wherein R² and R²’ are each independently, same or different from each other, CH2-R²¹, with R²¹ being H or linear C1-C6 alkyl; preferably H or linear C1-C4 alkyl, more preferably H, methyl or ethyl, provided that R² and R²’ are not both methyl. 7. A process as claimed in any one of claims 1 to 5, wherein one of R² and R²’ is methyl, and the other is of the formula CH2-R²¹, with R²¹ being linear or branched C1-C6-alkyl; preferably linear or branched C1-C4-alkyl; more preferably methyl or ethyl. 8. A process as claimed in any one of claims 1 to 5, wherein neither R² nor R²’ are methyl; preferably wherein R² and R^2’ is each independently, same or different from each other, CH2-R²¹, with R²¹ being linear or branched C1-C6-alkyl, more preferably linear or branched C1-C4-alkyl, even more preferably methyl or ethyl, yet more preferably methyl. 9. A process as claimed in any one of the preceding claims, wherein R¹ are each independently, same or different from each other, C1-C6 alkyl, preferably methyl. 10. A process as claimed in any one of the preceding claims, wherein cocatalyst (ii) is an aluminoxane cocatalyst, preferably in the absence of any further cocatalysts; and/or wherein the polymerization catalyst is supported on silica. 11. A process as claimed in any one of the preceding claims, wherein the process comprises the steps of (I) in a first polymerization step, preferably in at least one slurry reactor, polymerizing propylene and at least one comonomer selected from ethylene and C4- C10 alpha olefin comonomers, preferably ethylene, in the presence of the polymerization catalyst to produce a propylene copolymer matrix (A); and subsequently (II) in a second polymerization step, preferably in at least one gas reactor, polymerizing propylene and at least one comonomer selected from ethylene and C₄- C₁₀ alpha olefin comonomers; preferably at least two different comonomers selected from ethylene and C₄-C₁₀ alpha olefin comonomers; more preferably ethylene and at least one C₄-C₁₀ alpha olefin comonomer, in the presence of the polymerization catalyst and the propylene copolymer matrix (A) from step (I) to produce a propylene copolymer phase (B) dispersed in the propylene copolymer matrix (A). 12. A process as claimed in claim 11, wherein, in step (II), propylene is polymerized with at least two different comonomers selected from ethylene and C4-C10 alpha olefin comonomers, preferably ethylene and at least one C4-C10 alpha olefin comonomer, in the presence of the polymerization catalyst and the propylene copolymer matrix (A) from step (I) to produce a propylene terpolymer phase (B) dispersed in the propylene copolymer matrix (A); and, preferably, wherein: a) the propylene copolymer matrix (A) produced in step (I) is produced in an amount of less than or equal to 90 wt %, and b) the propylene terpolymer phase (B) produced in step (II) is produced in an amount of more than or equal to 10 wt %, of the total weight of the produced propylene terpolymer resin. 13. A process as claimed in any one claims 1 to 10, wherein the process is carried out in at least one slurry reactor, comprising the step of (I) polymerizing propylene and at least one comonomer selected from ethylene and C4-C10 alpha olefin comonomers; preferably at least two different comonomers selected from ethylene and C4-C10 alpha olefin comonomers; more preferably ethylene and at least one C4-C10 alpha olefin comonomer, in a slurry reactor to produce a propylene copolymer; and, preferably, (I) polymerising propylene and at least two different comonomers selected from ethylene and C4-C10 alpha olefin comonomers; more preferably polymerising propylene, ethylene and at least one C4- C10 alpha olefin comonomer in the slurry reactor to produce a propylene terpolymer. 14. A process as claimed in claim 13, wherein 50 to 99 wt% of the total weight of the propylene terpolymer resin end product is produced by the end of slurry step (I) and the process further comprises the step of (II) transferring the reaction mixture of step (I) into a gas phase reactor for producing propylene terpolymer amounting to 1 to 50 wt% of the propylene terpolymer resin end product.