JPH0662642B2 - Bis (2-substituted cyclopentadienyl) zirconium dihalide - Google Patents

Description

TECHNICAL FIELD The present invention relates to bis (2-substituted cyclopentadienyl) zirconium dihalide. The compound of the present invention is useful as a highly active catalyst component for olefin polymerization.

[Prior Art and Problems Thereof] Since it was found that a catalyst composed of bis (cyclopentadienyl) zirconium dichloride and methylaluminoxane polymerizes olefins with high activity (JP-A-58).
-19309, Makromol. Chem. Rapid Commun., 4
Vol. 417 (1983)), various zirconium compounds have been investigated as catalyst components for olefin polymerization.

Such zirconium compounds having a substituent on the cyclopentadienyl ring include bis (methylcyclopentadienyl) zirconium dichloride (J.
Chem.Soc. Dalton Trans., P. 805 (1981), bis (pentamethylcyclopentadienyl) zirconium dichloride (J. Amer. Chem. Soc., 100, 3078 (1978)), (pentamethylcyclopenta Dienyl) (cyclopentadienyl) zirconium dichloride (J. Amer. Chem. Soc., 106
Vol., Page 6355 (1984)). However, a zirconium compound having two disubstituted cyclopentadienyl groups as two ligands has not been synthesized so far.

Further, JP-A-60-35006 and JP-A-60-3
No. 5007, JP-A-60-3508, and JP-A-61-296008 disclose the general formula (C
₅ R ′ _m )) _p R ″ _s (C ₅ R ′ _m ) MeQ _3-p and R ″ _s (C ₅ R ′ _m ) ₂ MeQ ′ are described as catalysts. There is no description about the synthesis method and the physical properties.

[Object of the Invention] The present inventors have conducted research to synthesize a zirconium compound having two disubstituted cyclopentadienyl groups as two ligands as a novel compound useful as a catalyst component for olefin polymerization. It was also confirmed by polymerization experiments that the novel compound was successfully obtained by the synthetic routes of the formulas (1) and (2) described below, and that the compound was useful as a catalyst component for olefin polymerization.

As is clear from the above description, an object of the present invention is to provide a novel and useful compound as described above and its use.

[Structure of the Invention] The compound of the general concept of the zirconium compound of the present invention is represented by the following general formula [III].

(However, R ¹ is a substituent on the cyclopentadienyl ring and is an alkyl group having 1 to 5 carbon atoms, ▲ R ¹ ₂ ▼ -C ₅ H
₃ represents a 2-substituted cyclopentadienyl group, and X represents a halogen atom. The compound [II] of the present invention has a disubstituted cyclopentadienyl group as a ligand and has the following structure [I].

(However, ^{R 1,} ▲ figures previous R ¹ ₂ ▼ _-C 5 _{H 3} and X have the same meanings as defined above. The ^{R 1} defines the position of the cyclopentadienyl ring of ^{R 1.)} As the zirconium compound of the present invention, in the general formula [II], R ¹ is a hydrocarbon group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group and a pentyl group. And preferably a methyl group or an ethyl group. X is fluorine, chlorine,
It is a halogen atom such as bromine or iodine, preferably chlorine.

The synthetic route of the compound [II] of the present invention can be abbreviated as follows.

▲ R ¹ ₂ ▼ -C ₅ H ₄ + n-BuLi → (▲ R ¹ ₂ ▼ -C ₅ H ₃ ) + n-Butane ...
^{(1) 2Li (▲ R 1} 2 ▼ -C 5 H 3) + ZrX 4 → (▲ R 1 2 ▼ -C 5 H 3) 2 ZrX 2 + 2LiX ...
(2) (However, R ¹ , ▲ R ¹ ₂ ▼ -C ₅ H ₃ and X have the same meanings as described above.) The 2-substituted cyclopentadiene includes 1,2- ▲ R ¹ ₂ ▼ -C.
₅ H ₄ And / or And / or And 1,3- ▲ R ¹ ₂ ▼ -C ₅ H ₄ And / or And / or There are two types, the present invention is the latter, that is, 1,3-
▲ is of _{^{R 1 2 ▼ -C 5 H 4}} .

The production method of this type of compound is known as follows.
Bull.Soc.Chim.Fr., p. 2981 (1970), J. Chem.S.
oc., p. 1127 (1952), Tetrahedron, vol. 19, p. 1939 (1963),
ibid, 21, pp. 2313 (1985) and J. Org. Chem., 38, 397.
See page 9 (1971).

Such a 2-substituted cyclopentadiene can be lithiated with alkyl lithium and used as a 2-substituted cyclopentadienyl lithium in the next reaction. It can also be used as 2-substituted cyclopentadienyl potassium or 2-substituted cyclopentadienyl sodium.

The reaction between ZrX ₄ and Li (∇R ¹ ₂ ▼ -C ₅ H ₃ ) can be carried out using ethers, preferably tetrahydrofuran (THF) or 1,2-dimethoxyethane as a reaction solvent.

The reaction is preferably carried out at a Li (▲ R ¹ ₂ ▼ -C ₅ H ₃ ) / ZrX ₄ molar ratio of 1.9 to 3.0, especially 2.0 to 2.4. The reaction temperature is -20 ° C to 1
The range of 00 ° C, especially 0 to 30 ° C is preferable. The reaction is completed within 3 days if it is carried out at room temperature, but the reaction can be completed in a short time by heating.
The produced compound [II] can be purified by recrystallization or sublimation.

The zirconium compound [II] according to the present invention exhibits excellent olefin polymerization activity in the presence of aluminoxane and is a useful compound as a polymerization catalyst component. The aluminoxane used in the polymerization is generally (However, n is a number of 4 to 20, and R ² is a methyl group, an ethyl group, a propyl group, or a butyl group, preferably a methyl group.) And a linear aluminoxane represented by the general formula (However, n and R ² have the same meanings as described above.). Methods for producing compounds of this type are known. It is important that the linear and cyclic aluminoxanes have a degree of polymerization of at least 6, especially preferably 10 or more.

As the olefin used in the polymerization reaction, ethylene,
Propylene, 1-butene, 4-methyl-1-pentene,
[Alpha] -Olefin such as 1-hexene and 1-octene can be used, and two or more kinds of these components can be mixed and used for polymerization. The zirconium compound according to the present invention is a diene such as butadiene, 1,7-octadiene and 1,4-hexadiene, or norbornene, in addition to the above-mentioned α-olefin used for the polymerization of α-olefin. It is also effective for copolymerization with cyclic olefins such as dicyclopentadiene.

As the polymerization method, any of suspension polymerization, solution polymerization and gas phase polymerization is possible. The polymerization solvent for liquid phase polymerization, pentane, hexane, octane, decane, aliphatic hydrocarbons such as dodecane, cyclopentane, methylcyclopentane, cyclohexane, cycloaliphatic hydrocarbons such as cyclooctane, benzene, toluene, Aromatic hydrocarbons such as xylene, petroleum fractions such as gasoline, kerosene, and light oil are used. Of these, aromatic hydrocarbons are preferable.

The olefin pressure of the reaction system is normal pressure -50 kg / cm ² G, and the polymerization temperature is -50 ° C to 230 ° C, preferably -20.
It is in the range of ℃ to 200 ℃. The molecular weight at the time of polymerization can be controlled by known means, for example, selection of temperature or introduction of hydrogen.

There are no particular restrictions on the concentration and molar ratio of both the zirconium compound and the aluminoxane component according to the present invention in the above-mentioned polymerization system, but a Zr concentration of 10 ⁻⁴ to 10 is preferable.
^-9 mol / range, Al / Zr molar ratio is 10
A range of 0 or more, particularly 1000 or more is preferably used.

[Effect of the Invention] According to the method of the present invention, a novel zirconium compound having two disubstituted cyclopentadienyl groups as ligands can be obtained. If these zirconium compounds are used for olefin polymerization as a catalyst component for olefin polymerization, excellent polymerization performance can be obtained.

[Examples] Next, the present invention will be specifically described with reference examples and examples.

Reference Example 1 [Bis (1,2-dimethylcyclopentadienyl) zirconium dichloride] All reactions were carried out in an inert gas atmosphere. The reaction solvent used was previously dried. 2.0 g (21 mmol) of 1,2-dimethylcyclopentadiene in a 500 ml glass reaction vessel
Was diluted with 150 ml of tetrahydrofuran, and n-
16 ml of 15% butyllithium / hexane solution was added dropwise. After stirring at room temperature for 1 hour, the resulting solution of 1,2-dimethylcyclopentadienyllithium was cooled to 0 ° C., and 2.4 g (10 mmol) of zirconium tetrachloride was added to 5 g.
Added in portions.

The reaction solution was slowly warmed to room temperature and stirred for 12 hours. The solvent was distilled off under reduced pressure from the yellow solution containing white precipitate (LiCl), and then the product was sublimated (120 to 140 ° C./1 m).
mHg) to give the desired product as white crystals (0.25 g, yield 7%). The physical properties of this compound are shown below. The IR spectrum is obtained by the KBr method, ¹ H-NM
The R spectrum was based on the CDCl ₃ method (100 MHz).

Melting point: 252 to 254 ° C. Elemental analysis value: (C ₁₄ H ₁₈ Cl ₂ Zr) Calculated value (%): C; 48.26, H; 5.21 Measured value (%): C; 48.10, H 5.06 IR spectrum: shown in FIG.

NMR spectrum: shown in FIG.

Reference Example 2 [Polymerization] 450 ml of purified toluene and Toyo Stoufer
Chemical Co., Ltd. methylaluminoxane (molecular weight 90
9) 6.3 mmol and bis (1,2-dimethylcyclopentadienyl) zirconium dichloride 0.02 mmol were sequentially added, and the temperature was raised to 50 ° C. Then, propylene was continuously introduced into this so that the total pressure was maintained at 8 kg / cm ² G, and polymerization was carried out for 4 hours. As a result, 300 g of atactic polypropylene was obtained. The catalytic activity was 164 kg / gZr.

Example 1 [Bis (1,3-dimethylcyclopentadienyl) zirconium dichloride] All reactions were carried out under an inert gas atmosphere. The reaction solvent used was previously dried. 500 ml
In a glass reaction vessel, 3.4 g (36 mmol) of 1,3-dimethylcyclopentadiene was diluted with 150 ml of tetrahydrofuran, and 24 ml of a 15% butyllithium / hexane solution was added dropwise. After stirring at room temperature for 1 hour, the resulting solution of 1,3-dimethylcyclopentadienyl lithium was cooled to 0 ° C., and zirconium tetrachloride 3.
5 g (15 mmol) was added in 5 portions.

The reaction solution was slowly warmed to room temperature and stirred for 48 hours. The solvent was distilled off under reduced pressure from the yellow solution containing white precipitate (LiCl), and the mixture was extracted with 300 ml of methylene chloride and filtered. The yellow filtrate was concentrated, pentane was added, and the mixture was cooled to -30 ° C to obtain 1.7 g of white crystals. Sublimate the crystals (1
After purification at 30 to 140 ° C./1 mmHg), 1.1 g (yield 22%) of the desired product was obtained. The physical properties of this compound are shown below. The IR spectrum was based on the KBr method, and the ¹ H-NMR spectrum was based on the CDCl ₃ method (100 MHz).

Melting point: 175 to 176 ° C. Elemental analysis value: (C ₁₄ H ₁₈ Cl ₂ Zr) Calculated value (%): C; 48.28, H; 5.21 Measured value (%): C; 48.45, H 5.09 IR spectrum: shown in FIG.

NMR spectrum: shown in FIG.

Example 2 [Polymerization] 450 ml of purified toluene, Toyo Stoufer.RTM.
Chemical Co., Ltd. methylaluminoxane (molecular weight 90
9) 6.3 mmol and bis (1,3-dimethylcyclopentadienyl) zirconium dichloride 0.02 mmol were sequentially added, and the temperature was raised to 50 ° C. Then, propylene was continuously introduced into this so that the total pressure was maintained at 8 kg / cm ² G, and polymerization was carried out for 4 hours. As a result, 450 g of atactic polypropylene was obtained. The catalytic activity was 246 kg / gZr.

[Brief description of drawings]

1 and 3 show IR spectra of the following compounds, and FIGS. 2 and 4 show NMR spectra of the following compounds. FIGS. 1 and 2: bis (1,2-dimethylcyclopentadienyl). Zirconium Dichloride Figures 3 and 4: Bis (1,3-dimethylcyclopentadienyl) Zirconium Dichloride

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takaya Mise 21-11, Suwa Town, Kawagoe City, Saitama Prefecture (72) Inventor Hiroshi Yamazaki 2-41 Matsugaoka, Tokorozawa City, Saitama Prefecture (56) References 60-35006 (JP, A) JP-A-60-35007 (JP, A) Journal of Magnitude Resonance, 37 [3] (1980), 441-448

Claims (1)

[Claims] 1. The following formula [I] (However, R ¹ is a substituent on the cyclopentadienyl ring and is an alkyl group having 1 to 5 carbon atoms, ▲ R ¹ ₂ ▼ -C ₅ H ₃
Represents a 2-substituted cyclopentadienyl group, and X represents a halogen atom. ) Bis (2-substituted cyclopentadienyl) zirconium dihalide