JPH0662644B2 - Bis (4-substituted cyclopentadienyl) zirconium dihalide - Google Patents

Description

TECHNICAL FIELD The present invention relates to bis (4-substituted cyclopentadienyl) zirconium dihaland. The compound of the present invention is useful as a highly active catalyst component for olefin polymerization.

[Conventional technology and its problems]

Since it was found that a catalyst composed of bis (cyclopentadienyl) zirconium dichloride and methylaluminoxane polymerizes olefins with high activity (JP-A-58-1).
9309, Makromol. Chem. Rapid Commun., Volume 4, 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)), (pentamethylcyclo Pentadienyl) (cyclopentadienyl) zirconium dichloride (J. Amer. Chem. Soc., Vol. 106)
6355 (1984)) and the like have been synthesized. However,
A zirconium compound having a 4-substituted cyclopentadienyl group as two ligands has not been synthesized so far.

Further, JP-A-60-35006, JP-A-60-35007,
The JP 60-35008 and JP 61-296008 discloses the general formula _{(C 5 R m ') p} R s "(C 5 R m') M e
Although there is a description that a compound of Q _3-p and R _s ″ (C ₅ R _m ′) _{2 Me} Q ′ is used as a catalyst, there is no description about the synthetic method and physical properties of the compound.

[Object of the Invention]

The present inventors conducted research to synthesize a zirconium compound having the above-mentioned 4-substituted cyclopentadienyl group as two ligands as a novel compound useful as a catalyst component for olefin polymerization. Then, the novel compound is represented by the following formula (1) and
Succeeded in acquisition in the synthetic route of (2), and also
It was also confirmed by polymerization experiments 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 Invention]

The zirconium compound of the present invention is represented by the following general 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 ₄ ▼ -C ₅ H is a 4-substituted cyclopentadienyl group, and X is a halogen atom. .Also,
The number before R ¹ defines the position of R ^{1 on} the cyclopentadienyl ring. As the zirconium compound of the present invention, in the general formula [I], R ¹ is a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group,
A hydrocarbon group such as a pentyl group, preferably a methyl group or an ethyl group. X is a halogen atom such as fluorine, chlorine, bromine and iodine, preferably chlorine.

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

▲ R ¹ ₄ ▼ -C ₅ H ₂ ＋ n-BuLi → Li (▲ R ¹ ₄ ▼ −C ₅ H) ＋ n-Butane… (1) 2Li (▲ R ¹ ₄ ▼ −C ₅ H) ＋ ZrX ₄ → (▲ R ¹ ₄ ▼ -C ₅ H) ₂ ZrX ₂ + 2LiX ... (2) (However, R ¹ , ▲ R ¹ ₄ ▼ -C ₅ H and X have the same meanings as described above.) 4-substituted cyclopentadiene has 1 , 2,3,4- ▲ R ¹ ₄ ▼ −C ₅ H ₂
That is, And / or And / or There is only one type.

Methods for producing compounds of this type are known. That is, (Bull.
Soc.Chim.Fr., p. 2981 (1970), Tetrahedron, vol. 19, p. 1939 (1963), or J.Org.Che.
M., 38, 4071 (1973).

Such 4-substituted cyclopentadiene can be lithiated with alkyllithium and used as 4-substituted cyclopentadienyllithium in the next reaction. It can also be used as 4-substituted cyclopentadienyl potassium or 4-substituted cyclopentadienyl sodium.

The reaction between ZrX ₄ and Li (ΔR ¹ ₄ ▼ -C ₅ H) can be carried out using ethers, preferably tetrahydrofuran (THF) or 1,2-dimethoxyethane as a reaction solvent. The reaction _{^{is, Li (▲ R 1 4 ▼}} -C 5 H) / molar ratio of ZrX ₄ is 1.9 to 3.0,
In particular, it is preferably carried out in the range of 2.0 to 2.4. The reaction temperature is preferably in the range of -20 to 100 ° C, especially 50 to 90 ° C. The reaction is completed within 10 days if it is carried out at room temperature, but the reaction can be completed in a short time by heating. The produced compound [I] can be purified by recrystallization or sublimation.

The zirconium compound [I] 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, R ² is a methyl group, an ethyl group,
It is a propyl group or a butyl group, preferably a methyl group. ) Linear aluminoxane represented by (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 aluminoxane has a degree of polymerization of at least 6, especially 10 or more.

As the olefin used in the polymerization reaction, ethylene,
It is an α-olefin such as propylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene, and two or more kinds of them can be mixed and used for polymerization. The zirconium compound according to the present invention is a diene such as butadiene, 1,7-octadiene, 1,4-hexadiene, or norbornene, in addition to the above-mentioned α-olefin, which is used for the polymerization of α-olefin. It is also effective for copolymerizing cyclic olefins such as dicyclopentadiene and α-olefins.

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

The concentration of both the zirconium compound and the aluminoxane component according to the present invention in the above-mentioned polymerization system, the molar ratio is not particularly limited, but preferably Zr concentration of 10 ⁻⁴ to 10 ⁻⁹ mol /
The Al / Zr molar ratio is preferably 100 or more, particularly 1000 or more.

〔The invention's effect〕

According to the present invention, a novel zirconium compound having two 4-substituted 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.

〔Example〕

 Next, the present invention will be specifically described with reference to examples.

Example 1 [Bis (1,2,3,4-tetramethylcyclopentadienyl)
Zirconium dichloride] All reactions were performed under an inert gas atmosphere. The reaction solvent used was previously dried. In a 500 ml glass reaction vessel, 1,2,3,4-tetramethylcyclopentadiene 2.5 g (20 mmol) 1,2-dimethoxyethane 150 ml
15% solution of n-butyllithium / hexane diluted with
15 ml was added dropwise. After stirring at room temperature for 1 hour, the white suspension of 1,2,3,4-tetramethylcyclopentadienyllithium was cooled to 0 ° C., and 2.3 g (10 mmol) of zirconium tetrachloride was divided into 5 portions. added.

The reaction solution was heated and stirred under reflux for 72 hours. White precipitate (LiC
After distilling off the solvent from the yellow solution containing l) under reduced pressure, methylene chloride
It was extracted with 300 ml and filtered. The yellow filtrate was concentrated, pentane was added, and the mixture was cooled to −30 ° C. to obtain 0.16 g of white crystals. After sublimation (130 to 140 ° C./1 mmHg) purification, 0.13 g (yield 3
%) Of the desired product was obtained. The physical properties of this compound are shown below.
The IR spectrum is the KBr method, and the ^1H-NMR spectrum is CDCl ₃
According to the law (400MHz).

Melting point: 270 to 271 ° C Elemental analysis value: (C ₁₈ H ₂₆ Cl ₂ Zr) Calculated value (%): C; 53.44, H; 6.48 Measured value (%): C; 53.43, H; 6.49 IR spectrum: 1st Shown in the figure.

NMR spectrum: shown in FIG.

Example 2 [Polymerization] Purified toluene (450 ml), methylaluminoxane (molecular weight: 909) 6.3 mmol, and bis (1,2,3,4-, manufactured by Toyo Stoufer Chemical Co., Ltd.) were placed in a sus autoclave having an internal volume of 1.51 which was sufficiently replaced with nitrogen. Tetramethylcyclopentadienyl) zirconium dichloride (0.02 mmol) was 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. The result is atactic polypropylene 52
0 g was obtained. The catalytic activity was 285 Kg / gZr.

[Brief description of drawings]

Figure 1 shows the IR spectra of the following compounds, and Figure 2 shows MN.
The R spectrum is shown. Figures 1 and 2: Bis (1,2,3,4-tetramethylcyclopentadienyl) 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)

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 ₄ ▼ -C ₅ H is a 4-substituted cyclopentadienyl group, and X is Represents a halogen atom)
A bis (4-substituted cyclopentadienyl) zirconium dihalide represented by: