JP2001097988A - Ruthenium complex, polymerization catalyst and method for producing cyclic olefin polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metathesis polymerization catalyst exhibiting high polymerization activity at a low temperature and capable of producing a cyclic olefin polymer soluble in an organic solvent. SOLUTION: The novel ruthenium carbene complex represented by the general formula 1 having two imidazole carbene and two chlorines as ligands. (R is independently hydrogen, a methyl group or an ethyl group, X ¹ and X ² are independently hydrogen or a C1-20 alkyl group,
2-20 alkenyl / alkynyl groups or C6-20
And the hydrocarbon group may be substituted with halogen. )

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel ruthenium carbene complex, a polymerization catalyst comprising the complex, and a method for producing a cyclic olefin polymer. More specifically, the present invention relates to a novel ruthenium carbene complex having imidazole carbene as a ligand, a polymerization catalyst comprising the complex, and a method for producing a cyclic olefin polymer having excellent solubility in an organic solvent using the catalyst.

[0002]

2. Description of the Related Art Conventionally, as a catalyst for metathesis polymerization of cyclic olefins, a composite catalyst system mainly comprising a compound containing a transition metal such as tungsten or molybdenum has been mainly used. Also, recently, so-called “metal carbene complexes” in which various carbene are coordinated to osmium or ruthenium have been attracting attention as stable catalysts having low sensitivity to oxygen and moisture.

For example, Grubbs et al. Have reported that a ruthenium carbene complex represented by the following formula 2 in which two phosphines having a bulky alkyl group or an aryl group such as tricyclohexylphosphine is coordinated is norbornene, tetracyclododecene (TCD) Have high metathesis polymerization activity even for cyclic olefins such as dicyclopentadiene (DCPD) (J.A.).
m. Chem. Soc. , 1996, 118, 10
Page 0).

[0004]

Embedded image (In the formula 2, R is a cycloalkyl group or a phenyl group, and Ph is a phenyl group.)

On the other hand, Herrmann et al. Synthesized a ruthenium carbene complex represented by the following formula 3 in which bulky phosphine in the ruthenium carbene complex represented by the above formula 2 was changed to diisopropylimidazole carbene.
It has been reported that this compound is a highly active metathesis catalyst for the polymerization of cyclic olefins as in the case of the above-mentioned Grubbs et al. Catalyst (Angew. Chem. Int. En.
gl. 1996, 35, 2805).

[0006]

Embedded image (In the formula 3, iPr is an isopropyl group, and Ph is a phenyl group.)

The catalyst reported by Grubbs et al. Generally causes metathesis polymerization of cyclic olefins with high activity, but the resulting polymer is known to have a specific trans structure. Therefore, a polymer obtained from a highly symmetric monomer such as DCPD or TCD as a cyclic olefin becomes insoluble in many organic solvents,
This is a problem in industrial production due to precipitation from a solvent during the polymerization process. Also, with the catalyst reported by Herrmann et al., The resulting polymer had a 25% cis structure.
It is soluble in organic solvents due to its content. However, the catalytic activity greatly depends on the polymerization temperature, and there has been a problem that as the temperature is lowered, the polymerization activity is remarkably reduced.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a novel olefin polymer which exhibits high polymerization activity at a low temperature and is soluble in an organic solvent. Another object of the present invention is to provide a novel metathesis polymerization catalyst.

[0009]

Means for Solving the Problems The present inventors have synthesized various ruthenium carbene complexes, evaluated their metathesis polymerization activity at a low temperature, and conducted intensive studies on the solubility of the obtained polymers in organic solvents. As a result, it was found that the use of a ruthenium carbene complex having a specific ligand reduces the temperature dependence of polymerization activity, and that the solubility of the polymer in an organic solvent is improved. It was completed.

Thus, according to the present invention, the following general formula 1

Embedded image

(Wherein, R represents each independently hydrogen, a methyl group or an ethyl group. X ¹ and X ² each independently represent hydrogen or an alkyl group having 1 to 20 carbon atoms, 2 to 20 carbon atoms.
A hydrocarbon group selected from the group consisting of an alkenyl group, an alkynyl group having 2 to 20 carbon atoms and an aryl group having 6 to 20 carbon atoms, and the hydrocarbon group may be substituted with a halogen atom. The present invention provides a ruthenium carbene complex represented by the formula: In the above formula 1, R is independently hydrogen, methyl or ethyl, X ¹ is hydrogen, and X ² is preferably a phenyl group which may be substituted with a halogen atom.

Further, according to the present invention, there is provided a polymerization catalyst comprising a ruthenium carbene complex represented by the aforementioned general formula 1. Further, according to the present invention, there is provided a method for producing a polymer, comprising subjecting a cyclic olefin to metathesis polymerization in the presence of the catalyst represented by the general formula 1. In the above production method, a polymer having a cis content of 30% or more in the main chain structure of the polymer can be produced particularly preferably.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Ruthenium Carbene Complex The ruthenium carbene complex of the present invention is represented by the above general formula 1. Hereinafter, the components of the complex will be specifically described. The central metal is ruthenium, and chlorine, an imidazole carbene having a substituent R, and a methylene carbene to which the substituents X ¹ and X ² are bonded are coordinated to the ruthenium as a ligand (ligand).

The substituents R of the imidazole carbene are each independently selected from hydrogen, methyl and ethyl. Of these, an ethyl group is preferred. Specific examples of imidazole carbene include imidazole, N-methylimidazole, N-ethylimidazole, N, N'-
Dimethylimidazole and N, N'-diethylimidazole are mentioned. Among these, N, N'-dimethylimidazole, N-ethyl-N'-methylimidazole,
N, N'-diethylimidazole is preferred, and N, N '
-Diethylimidazole is particularly preferred. The two imidazolecarbenes coordinated to ruthenium may have the same structure or different structures, but preferably have the same structure.

The substituents X ¹ and X ² of methylenecarbene each independently represent hydrogen or an alkyl group having 1 to 20 carbon atoms, an alkenyl group and an alkynyl group having 2 to 20 carbon atoms, and 6 to 20 carbon atoms. A hydrocarbon group selected from the group consisting of aryl groups. The hydrocarbon group may be substituted with a halogen atom. 1-20 carbon atoms
Specific examples of the alkyl group of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl,
Hexyl, octyl, cyclopentyl, cyclohexyl and the like can be mentioned. Preferred are methyl, ethyl, propyl and isopropyl. More preferably, they are methyl and ethyl.

Specific examples of the alkenyl group having 2 to 20 carbon atoms include vinyl, propenyl, butenyl, pentenyl and the like. Preferred are vinyl, propenyl and butenyl. More preferred are vinyl and propenyl. Specific examples of the alkynyl group having 2 to 20 carbon atoms include:
Ethynyl, propynyl, butynyl, pentynyl, hexynyl and the like. Preferred are ethynyl, propynyl and butynyl. More preferred are ethynyl and propynyl. Specific examples of the aryl group having 6 to 20 carbon atoms include phenyl, tolyl, xylyl, mesityl, naphthyl, indenyl, fluorenyl, pyrenyl, anthracenyl, phenanthryl, anthryl and the like.
Preferred are phenyl, tolyl, xylyl, mesityl, and more preferred is phenyl.

The above-mentioned hydrocarbon group may be substituted by a halogen atom. The halogen atom is not particularly limited,
Chloro is preferred. Specific examples of the hydrocarbon group substituted with a halogen atom include chloromethyl, α-chloroethyl, β-chloroethyl, α-chlorovinyl, γ-chloropropenyl, 2-ethynyl, α-chloropropynyl,
-Chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2,4-dichlorophenyl, 3,5-dichlorophenyl, 2-fluorophenyl, 4-bromophenyl and the like. Among these, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2,4
-Dichlorophenyl and 3,5-dichlorophenyl are preferred.

Preferred specific examples of the ruthenium carbene complex represented by the general formula 1 include bis (N, N'-diethylimidazoleylidene) benzylideneruthenium dichloride and bis (N, N'-methylimidazoleylidene) benzylideneruthenium dichloride. , Bis (imidazoleylidene) benzylidene ruthenium dichloride, (N, N'-diethylimidazoleylidene)
(N, N′-dimethylimidazoleylidene) benzylidene ruthenium dichloride, (N, N′-diethylimidazoleylidene) (imidazoleylidene) benzylideneruthenium dichloride, (N, N′-dimethylimidazoleylidene) (imidazoleylidene) ) Benzylidene ruthenium dichloride, bis (N, N'-diethylimidazoleylidene) (4-chlorobenzylidene) ruthenium dichloride, bis (N, N'-dimethylimidazoleylidene) (4-chlorobenzylidene)
Examples include ruthenium dichloride and bis (imidazoleylidene) (4-chlorobenzylidene) ruthenium dichloride. Of these, bis (N, N′-diethylimidazoleylidene) benzylidene ruthenium dichloride is most preferred.

The ruthenium carbene complex of the present invention can be produced by using the ruthenium complex represented by the above formula 2 as a raw material by an exchange reaction between phosphine and imidazole carbene. As the phosphine represented by the formula 2,
There is no particular limitation as long as the exchange reaction can be performed with imidazole carbene, and examples thereof include triphenylphosphine, triisopropylphosphine, tributylphosphine, tricyclopentylphosphine, and tricyclohexylphosphine. As a method for synthesizing the imidazole carbene, R-amine (R is hydrogen,
Methyl and ethyl) and paraformaldehyde and glyoxal by dehydration and condensation in the presence of hydrochloric acid to give imidazole hydrochloride, and then to carbene in the presence of liquid ammonia in the presence of sodium or potassium-tert-butoxide catalyst. As long as the imidazole carbene can be synthesized, the method is not particularly limited to these methods.

Method for Producing Cyclic Olefin Polymer The ruthenium carbene complex of the present invention is used as a polymerization catalyst for metathesis-polymerizing a cyclic olefin. Examples of the cyclic olefin to be polymerized include (1) polycyclic olefins having a norbornene ring such as norbornenes, dicyclopentadienes, and tetracyclododecenes; and (2) monocyclic olefins. Can be used. These cyclic olefins are
It may have a substituent such as an alkyl group, an alkenyl group, or an alkylidene group, may have a polar group, and may further have a double bond other than the double bond of the norbornene ring. .

Among these cyclic olefins, it is preferable to use tricyclic to hexacyclic cyclic olefins having a norbornene ring in order to obtain a ring-opened polymer having excellent heat resistance and solubility. Among them, tricyclic cyclic olefins such as dicyclopentadiene and tetracyclic cyclic olefins such as tetracyclododecene are more preferable. Tricyclic cyclic olefins such as dicyclopentadiene are particularly preferred. Specific examples of dicyclopentadienes, that is, tricyclic cyclic olefins having a norbornene ring include dicyclopentadiene and methyldicyclopentadiene, and include a double bond in the 5-membered ring portion of dicyclopentadiene. Saturated tricyclo [4.3.1 ^2,5 . 0] -dec-3-ene and the like.

The tetracyclododecenes include those represented by the following general formula 4.

Embedded image

(Wherein R _{5 to} R ₁₂ are hydrogen, and have 1 to 3 carbon atoms)
R _{13 to} R ₁₆ represent hydrogen, a hydrocarbon group having 1 to 20 carbon atoms or a substituent containing halogen, silicon, oxygen or nitrogen, and R ₁₃ and R ₁₆
May combine with each other to form a ring. )

Specific examples of tetracyclododecenes include (a) tetracyclododecene, 8-methyltetracyclododecene, and 8-ethyltetracyclododecene having no double bond other than the norbornene ring. , 8-
Tetracyclododecene such as cyclohexyltetracyclododecene and 8-cyclopentyltetracyclododecene, and those having a substituent on the above tetracyclododecenes; and (b) a double bond other than a norbornene ring. As those having, 8-methylidenetetracyclododecene, 8-ethylidenetetracyclododecene, 8
Tetracyclododecenes having a double bond outside the ring, such as -vinyltetracyclododecene, 8-propenyltetracyclododecene, 8-cyclohexenyltetracyclododecene, and 8-cyclopentenyltetracyclododecene; (C) having an aromatic ring,
Phenyltetracyclododecene and the like; (d)
Examples of the compound having a polar group include 8-methoxycarbonyltetracyclododecene, 8-hydroxymethyltetracyclododecene, 8-carboxytetracyclododecene, tetracyclododecene-8,9-dicarboxylic acid and anhydrides thereof. Tetracyclododecenes having an oxygen-containing substituent; tetracyclododecenes having a nitrogen-containing substituent such as 8-cyanotetracyclododecene, tetracyclododecene-8,9-dicarboxylic imide; 8-chlorotetrade Tetracyclododecenes having a halogen-containing substituent such as cyclododecene; and tetracyclododecenes having a silicon-containing substituent such as 8-trimethoxysilyltetracyclododecene.

As specific examples of other cyclic olefins having a norbornene ring, bicyclic ones having one norbornene ring include norbornene, 5-methylnorbornene, 5-ethylnorbornene, 5-butylnorbornene, Norbornenes such as -hexylnorbornene, 5-cyclohexylnorbornene and 5-cyclopentylnorbornene, and corresponding oxanorbornenes; norbornenes having an extracyclic double bond such as 5-ethylidene norbornene, 5-vinyl norbornene and 5-propenyl norbornene And the corresponding oxanorbornenes.

Examples of one having one norbornene ring and one six-membered ring include hexacycloheptadecene, 12-methylhexacycloheptadecene, 12-hexylhexacycloheptadecene, 12-cyclohexylhexacycloheptadecene, and 12-cyclopentyl. Hexacycloheptadecenes such as hexacycloheptadecene, 12-ethylidenehexacycloheptadecene, 12-vinylhexacycloheptadecene, 12-cyclohexenylhexacycloheptadecene, and 12-cyclopentenylhexacycloheptadecene. Examples of those having a norbornene ring and an aromatic ring include 5-phenylnorbornene, 5-phenyloxanorbornene, 1,4-methano-1,4,4a, 9a-tetrahydrofluorene,
1,4-methano-1,4,4a, 5,10,10a-hexahydroanthracene and the like.

Examples of those having a polar group include 5-methoxycarbonylnorbornene, norbornenyl-2-methylpropionate, norbornene-5,6-dicarboxylic anhydride, 5-hydroxymethylnorbornene,
Norbornenes having an oxygen-containing polar group such as-or 5,6-di (hydroxymethyl) norbornene, 5,6-dicarboxynorbornene, 5-methoxycarbonyl-6-carboxynorbornene; 5-methoxycarbonyloxanorbornene, Methyl-5-methoxycarbonyloxanorbornene, oxanorbornenyl-
2-methylpropionate, oxanorbornene-5
6-dicarboxylic anhydride, 5-hydroxymethyloxanorbornene, 5,5- or 5,6-di (hydroxymethyl) oxanorbornene, 5-hydroxy-6-propyloxanorbornene, 5,6-dicarboxyoxanorbornene and the like Oxanorbornenes having an oxygen-containing polar group: norbornenes having a nitrogen-containing polar group such as 5-cyanonorbornene and norbornene-5,6-dicarboxylic imide; 5-cyanooxanorbornene, oxanorbornene-5,6-dicarboxylic acid Oxanorbornenes having a nitrogen-containing polar group such as acid imide are exemplified.

Among the other cyclic olefins having a norbornene ring, from the viewpoints of heat resistance and solubility,
Those having a norbornene ring and an aromatic ring are preferable, and may be copolymerized with the above-mentioned cyclopentadiene, tetracyclododecene or the like. The monocyclic olefins or diolefins have 4 to 20 carbon atoms, and preferably 4 to 20 carbon atoms.
10 cyclic olefins or diolefins and their derivatives. Specific examples thereof include JP-A-64-6621 such as cyclobutene, cyclopentene, methylcyclopentene, cyclohexene and cyclooctene.
6, monocyclic cycloolefin monomers; cyclohexadiene, methylcyclohexadiene,
Examples thereof include cyclic olefin monomers such as cyclooctadiene and phenylcyclooctadiene described in JP-A-7-258318.

The above-mentioned cyclic olefins can be used alone or in combination of two or more. It is also preferable to copolymerize dicyclopentadienes or tetracyclododecenes with a cyclic olefin copolymerizable therewith. In this case, it is preferable to use 10% by weight or more of dicyclopentadiene or tetracyclododecene based on the total monomer polymerization. The ratio of the polymerization catalyst of the present invention to the cyclic olefin is usually from 1: 100 to 1: 2,000,000 (mol / mol) as (metal ruthenium in the polymerization catalyst: cyclic olefin).
Preferably 1: 500 to 1,000,000 (mol / mol), more preferably 1: 1,000 to 1: 500,0.
00 (mol / mol). If the amount of the catalyst is too large, it becomes difficult to remove the catalyst from the polymer, and if the amount is too small, sufficient polymerization activity cannot be obtained. The polymerization reaction can be performed in the presence or absence of a solvent. However, since the cyclic olefin polymer obtained by polymerization using the catalyst of the present invention is soluble in a solvent, a polymerization reaction using a solvent can be advantageously performed.

The polymerization solvent is not particularly limited, and is selected from aliphatic hydrocarbons, aromatic hydrocarbons, heteroatom-containing hydrocarbons and the like. Aliphatic hydrocarbons include butane, pentane, cyclopentane, hexane,
Examples thereof include cyclohexane, methylcyclohexane, octane, and cyclooctane. Examples of the aromatic hydrocarbon include benzene, toluene, xylenes, cumene, and naphthalene. Examples of the hetero atom-containing hydrocarbon include ether compounds such as diethyl ether, dipropyl ether, and tetrahydrofuran (THF), acetone, methyl ethyl ketone, and methyl isobutyl ketone (M
Examples include ketone compounds such as IBK), cyclopentanone and cyclohexanone, esters such as ethyl acetate and butyl acetate, and halogen compounds such as methylene chloride, chloroform, carbon tetrachloride, and chlorobenzene. From the viewpoint of toxicity, hexane, cyclohexane, methylcyclohexane, octane, toluene, and xylenes are preferred.

The reaction temperature may be any temperature which is generally used industrially for the polymerization of cyclic olefins.
A range of from 0C to 200C is recommended. More preferably 20
C. to 150C. Since the ruthenium carbene complex catalyst of the present invention exhibits high catalytic activity even at low temperatures,
Polymerization can be advantageously performed even in a low temperature range of -60 ° C. The reaction time may be within the range usually used industrially,
For example, 30 minutes to 24 hours are recommended. Preferably 1
The time is from 12 hours to 12 hours.

As described above, a polymer obtained by subjecting a cyclic olefin to metathesis polymerization using the ruthenium carbene complex of the present invention as a polymerization catalyst has a high cis content of 30% or more, and exhibits cyclohexane, methylcyclohexane, It is soluble in various organic solvents of medium polarity or low polarity such as octane, toluene, xylene, THF, methylene chloride, chloroform, carbon tetrachloride, and chlorobenzene. Therefore, when polymerization is performed using an organic solvent, the polymer is not insolubilized during the polymerization and does not precipitate.

Here, “cis content” indicates the ratio of the cis structure of the main chain double bond of the metathesis polymer. The cis structure when norbornadiene undergoes ring-opening metathesis polymerization is shown in the following formula 5. The method for measuring the “cis content” is well known in the art and can be measured by any method.
Infrared spectroscopy, ¹³ C-NMR analysis, ¹ H-NMR analysis and the like are recommended.

[0034]

Embedded image

Hereinafter, a synthesis example of the ruthenium carbene complex of the present invention and an application example as a polymerization catalyst will be specifically described. In Examples 1 and 2, the compounds to be synthesized were identified by ¹ H-NMR analysis, and the obtained chemical shifts were shown.

[0036]

EXAMPLES Example 1 Synthesis of bis (N, N'-diethylimidazoleylidene) benzylidene ruthenium dichloride Paraformaldehyde (0.15 mol, 4.5 g) was suspended in toluene (25 ml), and the temperature was adjusted to 5-7. Ethylamine (70% aqueous solution, 0.3 mol, 1.9)
3g) was added dropwise over 50 minutes. After completion of the dropwise addition, the mixture was further stirred for 5 minutes. This was added at 10 ° C with 6N hydrochloric acid (25
ml, 0.15 mol) was added over 20 minutes. 1
Warm to 5 ° C and add 40% -glyoxal (2
(1.8 g, 0.15 mol) was added over 10 minutes. After stirring for 1 hour (the solution was pale yellow), 25 ml of toluene was added. Water was removed by azeotropic distillation (the solution was reddish brown). The solvent was removed from the reaction solution by an evaporator to obtain a reddish brown viscous liquid N, N'-diethylimidazolium chloride (Et salt). [CH ₃ ^* CH _2- : δ = 1.5 ppm, CH ₃ CH ₂ ^* -:
δ = 4.25 ppm CH ^* = CH: δ = 7.5 ppm, CH ^* = N: δ = 8.
8 ppm] THF dehydrated from Et salt (0.94 g, 5 mmol)
(20 ml), and sodium hydride (18 ml) was added thereto.
(0 mg, 7.5 mmol). This was cooled to -60 ° C and ammonia (50 ml) was added for about 10 minutes.
Was introduced into the reaction system. The reaction temperature was kept at -40 ° C and the mixture was stirred for 2 hours. The Et salt disappeared with the progress of the reaction. After the reaction, the system was returned to room temperature to remove ammonia. The reaction was filtered under reduced pressure using celite and washed with toluene. The filtrate was evaporated to remove THF. Toluene was further added thereto to adjust the total amount to 40 ml, thereby preparing a 0.125 mmol / ml carbene solution.

Bis (tricyclohexylphosphine) benzylidene ruthenium dichloride (0.5 mmol)
Was dissolved in 15 ml of toluene. To this, the carbene solution (0.125 mmol / ml, 1.1 mmol) was added dropwise over 10 minutes. After reacting at room temperature for 45 minutes, the solvent was removed with an evaporator. The residue was dissolved in 1 ml of methylene chloride and precipitated as a solid with 20 ml of pentane. This was filtered under reduced pressure and collected by filtration. This operation 2
Repeat to obtain the desired product. [CH ₃ ^* N: δ = 4.1 ppm, CH ^* = CH ^* : δ =
7.8 ppm, NCH ^* N: δ = 10.0 ppm]

Example 2 Synthesis of bis (N, N'-dimethylimidazoleylidene) benzylidene ruthenium dichloride N-methylimidazole (0.10 mol, 8.2 g)
Was dissolved in isopropanol (50 ml), iodomethane (0.12 mol, 17.0 g) was added at room temperature, and after completion of the addition, the mixture was heated and reacted under reflux for 8 hours. After completion of the reaction, the solution was cooled to room temperature, and N, N'-dimethylimidazolium iodide (Me salt) was precipitated as white crystals. This was collected by filtration, washed with ether and THF, and dried under vacuum to obtain 20.2 g of Me salt. The yield was 90%. _{^{[CH * 3 N: δ =}} 4.1ppm, CH * = CH *: δ =
7.8 ppm, NCH ^* N: δ = 10.0 ppm]

The above Me salt (1.12 g, 5 mmol)
Was suspended in dehydrated THF (20 ml), sodium hydride (180 mg, 7.5 mmol) was added thereto, and the mixture was cooled to -60 ° C, and ammonia (50 m
l) was introduced into the reaction system. As a result of stirring for 2 hours while maintaining the reaction temperature at −40 ° C., the Me salt disappeared with the progress of the reaction. After completion of the reaction, the reaction solution was returned to room temperature to remove ammonia, and the reaction product was filtered under reduced pressure using celite,
Further washing with toluene.

After the filtrate was removed by an evaporator to remove THF, toluene was added to make the total weight 40 ml, thereby preparing a 0.125 mmol / ml carbene solution.
Bis (tricyclohexylphosphine) benzylidene ruthenium dichloride (0.5 mmol) was added to toluene 1
5 ml and add the carbene solution (0.12
(5 mmol / ml, 1.1 mmol) was added dropwise in 10 minutes, and the mixture was reacted at room temperature for 45 minutes, and then the solvent was removed by an evaporator.

The residue obtained after removing the solvent was dissolved in 1 ml of methylene chloride, and 20 ml of pentane was added to precipitate a solid, which was then collected by filtration under reduced pressure. This operation was repeated twice to obtain a target substance, bis (N, N'-dimethylimidazoleylidene) benzylidene ruthenium dichloride. _{^{[CH * 3 N: δ =}} 4.1ppm, CH * = CH: δ = 1
0.0 ppm, CH ^* = CH ^* Ph: δ = 20.5 pp
m]

Example 3 Metathesis Polymerization of Dicyclopentadiene (DCPD) Using Bis (N, N'-diethylimidazoleylidene) benzylidene Ruthenium Dichloride Catalyst A 30-ml ampoule was charged with a magnetic stirrer, and the reactor was stoppered and replaced with nitrogen. There, DCPD (2 g, 15.1 mmol),
1-Hexene (19.1 mg, 0.23 mmol) and cyclohexane [solids concentration (Ts) = 20%] were added. After heating to a predetermined temperature, a toluene solution of a bis (N, N'-diethylimidazoleylidene) benzylidene ruthenium dichloride catalyst prepared in Example 1 was added to initiate polymerization. After a predetermined time, the mixture was allowed to cool and solidified with isopropanol to obtain a polymer. ¹³ C cis content of polymer
-NMR and the solubility of the organic solvent at 24 ° C. was measured. The polymerization temperature, the polymer yield, and the cis content of the polymer are shown in Table 1, and the solubility in the organic solvent is shown in Table 2.

Comparative Example 1 Metathesis Polymerization of DCPD Using Bis (tricyclohexylphosphine) benzylideneruthenium Dichloride Catalyst A 30 ml ampoule was charged with a magnetic stirrer, and the flask was stoppered and replaced with nitrogen. There, DCPD (2 g, 15.1 mmol),
1-Hexene (19.1 mg, 0.23 mmol) and cyclohexane (Ts = 20%) were added. After heating to a predetermined temperature, a toluene solution of the catalyst was added to initiate polymerization. After a predetermined time, the mixture was allowed to cool and solidified with isopropanol to obtain a polymer. Tables 1 and 2 show the polymerization conditions and the properties of the polymer.

Comparative Example 2 Metathesis Polymerization of DCPD Using Bis (N, N'-diisopropylimidazoleylidene) benzylidene Ruthenium Dichloride Catalyst A 30 ml ampoule was charged with a magnetic stirrer, and the reactor was stoppered and replaced with nitrogen. There, DCPD (2 g, 15.1 mmol),
1-Hexene (19.1 mg, 0.23 mmol) and cyclohexane (Ts = 20%) were added. After heating to a predetermined temperature, a toluene solution of the catalyst was added to initiate polymerization. After a predetermined time, the mixture was allowed to cool and solidified with isopropanol to obtain a polymer. Tables 1 and 2 show the polymerization conditions and the properties of the polymer.

[0045]

[Table 1]

[0046]

[Table 2]

[0047]

The novel ruthenium carbene complex of the present invention is useful as a polymerization catalyst for cyclic olefins. When used as a catalyst in the polymerization of cyclic olefins, it exhibits extremely high polymerization activity even at low temperatures. Also, the resulting cyclic olefin polymer has a high cis content in the main chain structure,
It has good solubility in organic solvents and can prevent the precipitation of a polymer in the polymerization process.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazunori Taguchi 2-1-1, Yakko, Kawasaki-ku, Kawasaki-shi, Kanagawa F-term in the Zeon Corporation General Development Center (reference) 4H050 AA01 AA03 AA05 AB40 WB11 WB17 WB21 4J032 CA32 CA34 CA35 CA36 CA38 CA45 CD02 CE03

Claims (5)

[Claims] 1. A ruthenium carbene complex represented by the following general formula 1. Embedded image In the formula, Rs independently represent hydrogen, a methyl group or an ethyl group. X ¹ and X ² are each independently hydrogen or an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, and 6 to 2 carbon atoms.
0 is a hydrocarbon group selected from the group consisting of an aryl group, and the hydrocarbon group may be substituted with a halogen atom. 2. In the formula 1, R is independently hydrogen, methyl or ethyl, X ¹ is hydrogen, and X ² is a phenyl group which may be substituted with a halogen atom. Item 7. The ruthenium carbene complex according to Item 1. 3. A polymerization catalyst comprising the ruthenium carbene complex according to claim 1 or 2. 4. A method for producing a polymer, comprising subjecting a cyclic olefin to metathesis polymerization in the presence of the catalyst according to claim 3. 5. The cis content in the main chain structure of the polymer is 30.
%.