DE1568129B - Process for the dimerization of an alpha-olefin for the preparation of a product consisting primarily of straight-chain dimers with an internal double bond - Google Patents

Description

1 ■ 2 -

The invention relates to a process for the preparation. One had to expect, therefore, that the dimerization

one primarily composed of straight-chain dimers. of a «-olefin, for example propene, in the presence internal double bond through a catalyst that contains an activating agent, Dimerization of an α-olefin. . for example an aluminum trialkyl and a com-

Process for the dimerization of -olefins in 5 plex nickel compounds, for example nickel acetyl present of aluminum alkyls either alone as acetonate, lead to the production of a product Catalyst or in combination with a minor one, consisting primarily of branched-chain olefins Share of an activator are known. consists, for example, 2-methylpentene-1, and that

The British patent 713 081 (Ziegler) describes this process at lower temperatures than a process for the polymerization of ethylene, which could be carried out in the ethylene at a temperature of 60 to table patent 742 642.
250 ° C brought into contact with an activator It has now surprisingly been found that

which consists of hydrides of aluminum, gallium, propene using nickel acetyl indium and beryllium and derivatives of such hyacetonate and an organic aluminum compound, in which one or more hydrogen atoms under certain process conditions are converted into an atom by hydrocarbon radicals are replaced, primarily from straight-chain dimers with internal monovalent aromatic hydrocarbon radicals which can dimerize from the group of alkyl radicals and a product consisting of double bonds,
are selected. ■ - ■ - Accordingly, the method of the invention is for

In particular, British Patent 20 relates to making one primarily from straight chain Di-713 081 the polymerization of ethylene to butane-1-mers with an internal double bond and higher straight-chain -olefins by being brought into contact by dimerization of a -olefin of ethylene with aluminum triethyl at 200 indicates that propene is used at a temperature up to 220 ° C at subatmospheric pressure. between -40 and + 200 ° C and under such pressure-

British patent 742 642 (Ziegler) conditions that the reactants in one writes a process for the dimerization of a monoliquid or partially condensed state of geolefin with more than two hydrocarbons in hold, in the presence of a catalytically we-molecule, in which the monoolefin dimerizes at a temperature kenden dispersion or solution that by between 60 and 250 ° C in the presence of an activator introduction of nickel acetylacetonate, expediently with is heated, which consists of hydrides of beryllium, aluminum 30 less than 3 percent by weight moisture, and one miniums, gallium and indium as well as derivatives of organic aluminum compounds, preferably these Hydrides, in which one or more water nem aluminum alkyl alcoholate or one aluminum atom are replaced by hydrocarbon radicals, trialkyl, in a molar ratio of about 1.0: 0.8 to those from a group of alkyl radicals and monovalent about 1: 2 in an inert diluent, pre-aromatic Hydrocarbon residues exist. 35 preferably an aromatic compound or a

In particular, the British patent relates to aromatic halogen compounds 742 642 the dimerization of propene to a pro is.

product, which consists predominantly of 2-methylpentene-oil. The moisture content of the is expedient

in the case of propylene with aluminum triethyl in the case of nickel acetylacetonates down to below 3 Ge temperatures before use Reduced between 180 and 240 ° C at less than 40 percent by weight. The lower the humid atmosphere Pressure is brought into contact. In general, the better it is, the better it is.

British patent 773 536 (Ziegler) specifies a process for the catalytic polymer, preferably aluminum alkyl alcoholates, preferably Alusation of ethylene to form butene, hexenium diethylethylate. Aluminum trialkyls, e.g. B. aluminum or higher liquid or solid paraffin-like 45 miniumtriethyl, are also suitable.
Polymers or mixtures thereof in the presence of aluminum dialkyl alcoholates are preferred because

an aluminum trialkyl of the general formula they mildly with the complex organic compound

react, and catalysts become more consistent

, Ri quality achieved in subsequent preparation processes.

■ Al —R ⁵ ° E ^m 'S ^e other activating agents, e.g. aluminum

\ ² trialkyle, react more violently and make the tempe

re rature control of the catalyst preparation reaction

more difficult. As a result, it is more difficult to

in which R ₁ , R ₂ and R _{3 are} identical or dissimilar alkyls to obtain catalysts of consistent quality, the aluminum trialkyl being activated by nickel, 55 Nonetheless, useful catalysts are cobalt or platinum. gained from such agendas. Preferably will

In particular, the British patent relates to dimerization under pressure in the range of 773 536 the polymerization of ethylene to butene-1 14 to 140 atü carried out.

and higher straight-chain α-olefins, in which ethylene. Suitable diluents are usually

brought hydrogens with aluminum triethyl and a small amount of 60 liquid hydrocarbons and halogenated carbon-nickel acetylacetonate at 100 ⁰ C in contact. The preferred diluents are. aromatic and halogenated aromatic liquid

The advantage of the method of British patents, e.g. B. benzene, toluene, xylene and chlorobenzene, Writing 773 536 £ compared to the older to the state of the latter, the latter acts as a solvent for both catalysis technology belonging process, for example the 65 satellite components, creating a homogeneous catalybritic Patent 713 081, is said to be obtained in the fact sator system, which is from increased reliegen, that this process has a much lower producible activity compared to heterogeneous ones Temperatures can be carried out. Systems is.

The dimerization is carried out in the presence of a catalytic dispersion or solution.
^: The catalyst must be protected from contact with water,! Oxygen, alcohols, ethers, amines, phosphines, sulfur compounds, dienes, acetylenes, carbon monoxide and other complex ligands that displace olefins from transition metal complexes. The presence of substantial amounts of these materials will destroy or reduce the effectiveness of the catalyst.

. The method of the invention is illustrated in the following examples.

Example 1

2.5 g of anhydrous nickel acetylacetonate is slurried in 50 ml of cyclohexane at 0 ⁰ C. 2.5 ml of aluminum triethyl are added dropwise to the mixture, which is magnetically stirred for 30 minutes. The admixture was carried out in a dry, oxygen-free nitrogen atmosphere. The entire mixture was transferred into a 1 liter rocking autoclave made of stainless steel, which was then pressurized ^{with propene at 52.5 atmospheres and 40 ° C.} After a reaction time of 16 ¹ Z ₂ hours the entire reaction products in templates were collected, which were cooled with solid carbon dioxide and acetone. 114 g of residual liquid was recovered. This contained 26 g of cyclohexane solvent, 71 g of hexenes and 17 g of higher polymers. The hexene fraction contained 74 ° / ₀ linear hexenes, as appears from the following table.

Exact hexane analysis

percent

, ■ Hexen-1 ... '. ·: .. 5.0)

. Witches-2; .., 56, ol74

Hexen-3 13.0Y

. 4-methylpentene-1,2.0

4-methylpentene-2 4.0

2-methylpentene-2 12.0 _;

2-methylpentene-l 6.5

2,3-dimethylbutene-l 1.0

2,3-dimethylbutene-2 0.5.

Example 2

2.5 g of anhydrous nickel acetylacetonate were dissolved in 21 g of n-heptane at 0 to 5 ⁰ C to geschlemmt. 2.0 ml of diethyl aluminum ethylate was added dropwise to the mixture, which was magnetically stirred for 30 minutes. The admixture was carried out in an oxygen-free, dry nitrogen atmosphere. The entire mixture was then transferred to a 1 liter stainless steel Schaukelautoklaven which then atm with propene at 42 and 4O ⁰ C was pressurized. After a reaction time of 16 ¹ Z ₂ hours the entire reaction products in templates were collected, which were cooled by solid carbon dioxide and acetone. 70 g of total polymer was obtained. These consisted of 83 ⁰ Z ₀ hexenes. The hexene fraction containing 78 ° / ₀ linear hexenes and 8.3 ° / ₀ 2-methylpentene-2.

Examples 3 to 5

The procedure of Example 2 was repeated. Reaction conditions and product analyzes result from the following table 1:

table

at
game Ni
(AcAc) ₂
(G) AlEt ₂ OEt
cc
(as
lOVoige
Solution) Molver
ratio
Ni: Al 1.35 Solution and
Dilution
medium ADD £
Kata
time
Minutes itz at
ysator
tempera
door
⁰ C 7o what
ser in
Ni
(AcAc) ₂ Reak
ions
time
Stun
the Total-
Poly-
mer
(G) VeC
in the
Poly
mer Hey?
V.nC .ene
7o2MP ₂ Acti
vity
g / g / Ni
(AcAc) ₂
/H 2 2.5 2.0 1.0: 1.35 21g heptane 30th 0 to 5 2.7 17.8 70 85 78.0 8.3 1.6 (1) 3 2.5 2.0 1.0 1.0 26 g of toluene 15th Obis5 2.7 16.8 62 85 78.0 8.5 1.5 (5) 4th 2.5 1.5 1.0 1.35 50 g n-Hep
tan 15th 0 to 5 0.5 19.0 150 81 75.0 8.7 2.9 (8) 5 2.5 2.0 1.0 15 g 1/1 ben
zol n-Hep
tan 30th Obis5 2.7 16.5 115 87 79.0 7.4 2.8 (9)

The polymerization was ^{carried out at 40 °} C. and 42 atm.

Example 6 and

Example 2 was repeated in such a way that the heptane thinner was replaced by a toluene solvent, The reaction conditions and product analyzes result from the following table 2:

table

example

AlEt ₂ OEt Molver Ni cc ratio (AcAc) ₂ (as lO7oige Ni: Al (G) Solution) 1.0: 1.0 2.5 1.5 1.0: 1.0 2.5 1.5

Solution and
Diluents

Addition to
catalyst tempera
door 7o what Reak
ions Total- VoC, time ° C ser in
Ni
(AcAc) ₂ time
Stun Poly-
mer in the
Poly
mer Minutes Obis5 the (G) 15th Obis5 2.7 17.5 109 84 15th 0.5 16.8 113 88

Witches

7 »nC ₅ I% 2MP _S

Activity g / g / Ni (AcAc) ₃

6 2.5 1.5 1.0: 1.0 26 g of toluene

7 2.5 1.5 1.0: 1.0 50 g of toluene

The polymerization was ^{carried out at 40 °} C. and 42 atm.

78.5 77.5

7.4 7.5

Claims (2)

Patent claims: 1. A process for the preparation of a product consisting primarily of straight-chain dimers with an internal double bond by dimerization of an α-olefin, characterized in that propene is added at a temperature between -40 and +200 ⁰ C and under pressure conditions such that the reactants are in a liquid or partially condensed state, dimerized in the presence of a catalytically active dispersion or solution, which by introducing nickel acetylacetonate, advantageously with less than 3 percent by weight of moisture, and an organic aluminum compound, preferably an aluminum alkyl alcoholate or an aluminum trialkyl, in a molar ratio of about 1, 0: 0.8 to about 1: 2 in an inert diluent, preferably an aromatic compound or an aromatic halogen compound ". 2. The method according to claim 1, characterized in that that the dimerization is carried out at a pressure of 14 to 140 atmospheres.