CN103059059B - The preparation method of catalyst of ethylene trimerization and application thereof - Google Patents

Abstract

The invention relates to an ethylene trimerization catalyst, and discloses an indene-titanium metal complex substituted by a pendant aromatic heterocyclic group in a side chain, a preparation method thereof and an application in olefin oligomerization. The indene-titanium metal catalyst (I) described in the present invention has the following characteristics: R ¹ and R ² are the same or different C ₁ -C ₁₂ linear, branched or cyclic alkyl groups, or are formed by connecting the two C ₄ ~ C ₁₂ cyclic alkyl; R ³ ~ R ⁴ is hydrogen; R ⁵ is hydrogen, C ₁ ~ C ₁₂ linear, branched or cyclic alkyl or silyl; X is a halogen atom ; Y is sulfur. The indene-titanium complex catalyst with pendant aromatic heterocyclic group substitution in the side chain designed by the present invention has a good catalytic effect on ethylene oligomerization, and can catalyze ethylene trimerization with high activity in the presence of a co-catalyst, and there is no other catalyst in the trimerization product. The C6 isomer avoids the subsequent separation process, reduces the cost of industrialization, and can meet the needs of the industrial sector.

Description

Preparation method and application of ethylene trimerization catalyst

technical field

The invention relates to an olefin trimerization catalyst, in particular to a synthesis method of an indene-titanium metal catalyst substituted by a pendant aromatic heterocyclic group in the side chain and its application in alpha-olefin oligomerization.

Background technique

The post-processing industry using ethylene as raw material is an important field in the petroleum industry. Ethylene polymer products have been widely used in various fields in daily life; linear α-olefins (LAOs), which are oligomerized products of ethylene, are used in industry They also have important application value, they are widely used in the preparation of detergents, lubricants and plasticizers, especially 1-hexene and 1-octene are used as a comonomer to prepare linear low Density polyethylene (LLDPE) is widely used in chemical and chemical fields. At present, the ethylene oligomerization reaction catalyzed by most transition metal complex catalysts mainly obtains a multi-component olefin, which does not meet the market demand, especially the demand for single-component α-olefin. On the other hand, the activity and selectivity of existing single-component olefin oligomerization catalysts for catalyzing ethylene to 1-hexene are relatively sensitive to temperature. Therefore, it is of great research value and industrial application value to develop ethylene oligomerization catalysts with good temperature resistance and little influence of activity and selectivity on temperature (J.Org.Chem, 2004, 689(23), 3641-3668).

1-Hexene is an important comonomer for the preparation of LLDPE, which can be obtained by selective trimerization of ethylene. Phillips established the first industrial process for the production of 1-hexene in Qatar in 2003, based on a chromium catalyst. Chromium catalysts are currently the most studied and widely developed class of ethylene trimerization catalysts (Coord.Chem.Rev., 2011, 255, 861-880), but in view of the high toxicity of chromium-based catalysts, the use of chromium catalysts inevitably brings When it comes to environmental protection, finding highly active and highly selective catalysts based on other low-toxicity metals has become a research hotspot for scientists from all over the world. Among them, the trichloro-titanocene system with weak coordinating groups in the side chain is the most widely studied. In 2001, Hessen et al. used a cyclopentadienyl titanium trichloride complex with a benzene ring in the side chain to be activated by MAO to catalyze the trimerization of ethylene, and the catalytic activity could reach 131kg/(g-Ti h), of which 1 The -hexene selectivity reaches 86% (Angew. Chem. Int. Ed., 2001, 40, 2516-25). Afterwards, the Hessen research group conducted different substitution studies on the various components in the catalytic system with the general formula [η ⁵ -C ₅ H ₃ R-(B)-Ar)]TiCl ₃ /MAO (Organometallics, 2002, 21, 5122-5135), it was found that when there were trimethylsilyl large steric hindrance substituents on cyclopentadiene, the activity of the complex to catalyze ethylene trimerization was improved, and the most active pendant group was 3,5-dimethyl Benzene and cyclopentadienyl have trimethylsilyl-substituted titanium complexes, the catalytic activity can reach 21kg/(g-Ti h), but the selectivity drops to 84%, and the C ₁₀ product increases, which does not reach the high The selectivity is raised to a new height under the activity. Huang Jiling's research group recently found that indenyl titanium complexes with pendant aryl groups in their side chains are more active than cyclopentadiene systems (CN102161676A, 2011). But what they have in common is that the activity and selectivity are kept high only at low temperature, and then drop rapidly at high temperature. In 2003, Huang Jiling's research group synthesized and reported a group of trichloro-titanocene complexes with thienyl groups on the side chains of the cyclocene ring. This type of catalyst catalyzes ethylene to produce only 1-hexene and a small amount of polyethylene, and other low-carbon olefins Almost none, the catalytic ethylene trimerization results show that the highest activity is 220kg/(mol-Tih), and the 1-hexene selectivity is 86%. When the temperature is lowered and the selectivity is improved, then the decline of activity is accompanied by (Chem.Commun., 2003, 22, 2816-2817). Further modification of this type of complex found that when a large substituent trimethylsilyl is attached to the 4-position of the thiophene ring, the highest catalytic activity is 485 kg/(mol-Ti h), and the selectivity of 1-hexene is 90%. (CN101062961A, 2007), although the selectivity of these compounds is better, the highest activity occurs at 30°C.

With the development of science and technology, people hope to develop metal complex catalysts with higher activity and higher selectivity, which can still maintain high activity and ethylene trimerization selectivity at higher temperatures to meet the olefin selectivity. Gather production needs.

Contents of the invention

The technical problem to be solved by the invention is the preparation and application of a high-selectivity ethylene trimerization catalyst with good temperature resistance, so as to overcome the problems existing in the prior art and meet the needs of the industry.

One of the objectives of the present invention is to disclose a class of indene-titanium metal compounds with pendant aromatic heterocyclic group substitutions in their side chains.

The second object of the present invention is to disclose the preparation method of the indene-titanium metal compound substituted with a pendant aromatic heterocyclic group in the side chain.

The third object of the present invention is to disclose the application of the indene titanium metal compound substituted with a pendant aromatic heterocyclic group in the side chain as a catalyst in ethylene oligomerization.

The general structural formula of high selectivity of the present invention, highly active ethylene trimerization catalyst is as follows:

In formula (I), R ¹ and R ² are the same or different C ₁ -C ₁₂ linear, branched or cyclic alkyl groups, or C ₄ -C ₁₂ cyclic alkanes formed by connecting the two R ³ to R ⁵ are hydrogen, the same or different C ₁ to C ₁₂ linear, branched or cyclic alkyl or silyl groups; X is a halogen atom; Y is oxygen, sulfur or selenium.

R ¹ and R ² are the same or different C ₁ to C ₆ linear, branched or cyclic alkyl groups, or C ₄ to C ₇ cyclic alkyl groups formed by connecting the two; R ³ to R ⁵ is hydrogen, the same or different C ₁ -C ₆ linear, branched or cyclic alkyl or silyl groups; X is chlorine; Y is oxygen or sulfur.

More characteristically, R ¹ and R ² are cyclohexyl composed of both; R ³ is methyl or hydrogen; R ⁴ is hydrogen, R ⁵ is methyl or hydrogen or trimethylsilyl.

The preparation method of the indene titanium metal catalyst that the pendant aromatic heterocyclic group is substituted in the side chain of the present invention comprises the following steps:

Under the protection of an inert gas, the pendant aromatic heterocyclic group-substituted indene ligand compound and its isomers in the side chain are reacted with an alkyl alkali metal compound in an organic medium to generate a pendant aromatic heterocyclic group-substituted indene ligand base A metal salt; then add a certain amount of _TiCl4 to react with the alkali metal salt, drain the solvent, wash, dissolve and filter the remaining solid with an organic solvent, and then recrystallize the filtrate to obtain the target catalyst product.

Said alkyl alkali metal compound is selected from C ₁ -C ₄ alkyllithium, more preferably butyllithium.

The molar ratio of the pendant aromatic heterocyclic group substituted indene ligand compound to the alkyl alkali metal compound is 1:1-1.25.

The molar ratio of the alkali metal salt of the pendant aromatic heterocyclic group substituted indene ligand to the _TiCl4 is: 1:1-1.25.

The reaction temperature is 78-25°C, and the reaction time is 2-48 hours.

The organic solvent used is selected from one or more of tetrahydrofuran, diethyl ether, toluene, benzene, chloroform, methylene chloride, pentane, n-hexane and petroleum ether.

The indene ligand compound substituted by a pendant aromatic heterocyclic group in the side chain is a compound with the following general structural formula:

In formula (I), R ¹ and R ² are the same or different C ₁ -C ₁₂ linear, branched or cyclic alkyl groups, or C ₄ -C ₁₂ cyclic alkanes formed by connecting the two R ³ -R ⁵ are hydrogen, the same or different C ₁ -C ₁₂ linear, branched or cyclic alkyl or silyl groups; Y is oxygen, sulfur or selenium.

R ¹ and R ² are the same or different C ₁ to C ₆ linear, branched or cyclic alkyl groups, or C ₄ to C ₇ cyclic alkyl groups formed by connecting the two; R ³ to R ⁵ is hydrogen, the same or different C ₁ -C ₆ linear, branched or cyclic alkyl or silyl groups; Y is oxygen or sulfur.

More characteristically, R ¹ and R ² are cyclohexyl composed of both; R ³ is methyl or hydrogen; R ⁴ is hydrogen, R ⁵ is methyl or hydrogen or trimethylsilyl.

The present invention also provides the application and polymerization method of the above-mentioned catalyst in olefin polymerization.

Under the action of the co-catalyst, the above-mentioned catalyst can make the same or different C ₂ -C ₂₀ olefins oligomerize under the conditions of 0°C-110°C and 0.1-1.0 MPa. During the polymerization, the aluminum in the co-catalyst and the aluminum in the main catalyst The molar ratio of titanium Al:Ti=100-8000:1.

Cocatalysts include alkylaluminoxanes and Lewis acid type catalysts B(C ₆ F ₅ ) ₃ .

The alkylaluminoxane is preferably methylaluminoxane (MAO).

The molar ratio of aluminum in the cocatalyst to titanium in the main catalyst during polymerization is preferably Al:Ti=1000˜4000:1.

The C ₂ -C ₂₀ olefin used for polymerization may be one or more of α-olefins such as ethylene, propylene, butylene, and styrene. Among them, ethylene is preferable.

Catalysts can be used for homogeneous polymerization, and can also be used for heterogeneous polymerization after being supported. When using homogeneous polymerization, the solvent is selected from aliphatic or aromatic hydrocarbons, preferably toluene.

Experiments show that the designed side chain containing aromatic heterocyclic group-substituted indene-titanium complex has a good catalytic effect for ethylene oligomerization, especially ethylene selective trimerization; it can catalyze ethylene with high activity in the presence of a cocatalyst. Trimerization, the highest activity is 7×10 ⁵ g/(mol-Ti·h), the selectivity of 1-hexene is as high as 99%, and it has good temperature resistance, and the selectivity is maintained between 0 and 80 °C Stable, wherein the selectivity of 1-hexene is defined as: the mass of 1-hexene/(the mass of 1-hexene + the mass of other low-carbon olefins + the mass of polyethylene). Many subsequent separation operation links are avoided, the industrialization cost is reduced, and the needs of industrial production can be met.

Detailed ways

Example 1

Preparation of Substituted Indene Titanium Complex C1

(1) Preparation of Ligand Compound L1

At ~78°C, add 7.8g (40mmol) 6,6-pentylidene benzofulvene dropwise to 40mL ether solution of 2-thiophene lithium salt (40mmol), react at room temperature for 1 day, hydrolyze, and use 50mL petroleum The organic layer was extracted with ether, and purified by column chromatography (petroleum ether as a developing solvent) to obtain 2.23 g of a light yellow solid with a yield of 20%. The structural formula is as follows:

¹ HNMR (δ, ppm, CDCl ₃ ): 7.43-7.41 (m, 1H, Ind-H), 7.24-7.22 (m, 1H, Ind-H), 7.11-7.08 (m, 3H, thienyl-H, Ind -H), 6.89-6.87(m, 2H, thienyl-H, Ind-H), 6.42(t, J=2.0Hz, 1H, Ind-H), 3.38(d, J=2.0Hz, 2H, Ind- H), 2.50-2.42 (m, 2H, (CH ₂ ) ₅ ), 2.25-2.17 (m, 2H, (CH ₂ ) ₅ ), 1.70-1.60 (m, 4H, (CH ₂ ) ₅ ), 1.57- 1.47 (m, 2H, (CH ₂ ) ₅ )

(2) Preparation of complex C1

Add n-BuLi (6mmol) dropwise to ligand L1 (1.68g, 0.006mol) in 50mL n-hexane solution at 0°C, react overnight, add TiCl ₄ (0.006mol) at -78°C, react for 12-24h . The solvent was removed, washed with n-hexane, filtered, and the filtrate was concentrated at low temperature for recrystallization to obtain 390 mg of dark red crystals with a yield of 15%. The molecular structure of C1 is as follows:

¹ HNMR (δ, ppm, CDCl ₃ ): 7.95 (dd, J=8.8Hz, J=1.0Hz 1H, Ind-H), 7.70 (d, J=8.8Hz, 1H, Ind-H), 7.47 (ddd, J=8.4Hz, J=6.8Hz, J=1.0Hz, 1H, Ind-H), 7.35(ddd, J=8.4Hz, J=6.8Hz, J=1.0Hz, 1H, Ind-H), 7.20( dd, J=5.2, J=1.0Hz, 1H, thienyl-H), 7.18-7.15(m, 2H, Ind-H, thienyl-H), 7.00(d, J=3.6Hz, 1H, Ind-H) , 6.97(dd, J=5.2Hz, J=3.6Hz, 1H, thienyl-H), 2.91(dd, J=13.8, J=1.6Hz, 1H, (CH ₂ ) ₅ ), 2.77(td, J= 13.8, J=3.6Hz, 1H, (CH ₂ ) ₅ ), 2.68-2.54 (m, 1H, (CH ₂ ) ₅ ), 2.33-2.20 (m, 1H, (CH ₂ ) ₅ ), 1.87-1.65 ( m, 4H, (CH ₂ ) ₅ ), 1.57-1.39 (m, 2H, (CH ₂ ) ₅ ). Anal. Calcd. for C ₁₉ H ₁₉ Cl ₃ STi·0.25 (C ₆ H ₁₄ ): C, 54.09; H, 4.98. Found C, 53.67; H, 4.94%.

Example 2

Preparation of Substituted Indene Titanium Complex C2

(1) Preparation of Ligand Compound L2

At 78°C, add 9.4g (48mmol) of 6,6-pentylidene benzofulvene dropwise to 40mL of ether solution of 5-methyl-2-thiophene lithium salt (48mmol), react at room temperature for 1 day, and hydrolyze , the organic layer was extracted with 50 mL of petroleum ether, and purified by column chromatography (petroleum ether was used as a developing solvent) to obtain 4.2 g of a light yellow solid with a yield of 30%. The structural formula is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.47-7.41 (m, 1H, Ind-H), 7.36-7.31 (m, 1H, Ind-H), 7.16-7.01 (m, 2H, Ind-H), 6.72-6.68 (m, 1H, thienyl-H), 6.54 (s, 1H, thienyl-H), 6.42 (s, 1H, Ind-H), 3.39 (s, 2H, Ind-H), 2.47-2.37 ( m, 5H, 2(CH ₂ ) ₅ , thienyl-CH ₃ ), 2.27-2.10 (m, 2H, (CH ₂ ) ₅ ), 1.75-1.46 (m, 6H, (CH ₂ ) ₅ ).

(2) Preparation of complex C2

Add n-BuLi (6mmol) dropwise to ligand L3 (1.7g, 0.006mol) in 50mL petroleum ether solution at 0°C, react overnight, add TiCl ₄ (0.006mol) at -78°C, react for 12～ 24h. The solvent was removed, petroleum ether was added to wash, and the filtrate was concentrated at low temperature for recrystallization to obtain 1.4 g of deep red crystals with a yield of 52%. The molecular structure of C2 is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.99 (d, J=8.8Hz, 1H, Ind-H), 7.71 (d, J=8.8Hz, 1H, Ind-H), 7.53-7.45 (m, 1H , Ind-H), 7.40-7.31 (m, 1H, Ind-H), 7.16 (d, J=3.6Hz, 1H, Ind-H), 7.01 (d, J=3.6Hz, 1H, Ind-H) , 6.94 (d, J=3.6Hz, 1H, thienyl-H), 6.60 (dd, J=3.6, 0.8Hz, 1H, thienyl-H), 2.86 (dd, J=14.0, 2.8Hz, 1H, (CH ₂ ) ₅ ), 2.73(td, J=12.8, 3.6Hz, 1H, (CH ₂ ) ₅ ), 2.54(dd, 12.8, 3.6HZ, 1H, (CH ₂ ) ₅ ), 2.40-2.37(m, 3H , thienyl-CH ₃ ), 2.27-2.16 (m, 1H, (CH ₂ ) ₅ ), 1.85-1.65 (m, 4H, (CH ₂ ) ₅ ), 1.59-1.45 (m, 1H, (CH ₂ ) ₅ ), 1.44-1.31 (m, 1H, (CH ₂ ) ₅ ). Anal. Calcd. for C ₂₀ H ₂₁ TiCl ₃ S: C, 53.66; H, 4.73; found: C, 54.10; H, 5.03%.

Example 3

Preparation of Substituted Indene Titanium Complex C3

(1) Preparation of Ligand Compound L3

At 78°C, 9.4g (48mmol) of 6,6-pentylidene benzofulvene was added dropwise to 40mL of ether solution of 3-methyl-2-thiophene lithium salt (48mmol), reacted at room temperature for 1 day, and hydrolyzed , the organic layer was extracted with 50 mL of petroleum ether, and purified by column chromatography (petroleum ether was used as a developing solvent) to obtain 2.4 g of a light yellow solid with a yield of 17%. The structural formula is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.43 (d, J=7.2, 1H, Ind-H), 7.14-7.01 (m, 4H, 3Ind-H, thienyl-H), 6.69-6.61 (m, 1H , thienyl-H), 6.55-6.38(m, 1H, Ind-H), 3.41(s, 2H, Ind-H), 2.56-2.45(m, 2H, (CH ₂ ) ₅ ), 2.21-2.11(m , 2H, (CH ₂ ) ₅ ), 1.92-1.80 (m, 3H, thienyl-CH ₃ ), 1.75-1.56 (m, 5H, (CH ₂ ) ₅ ), 1.51-1.41 (m, 1H, (CH ₂ ) ₅ ).

(2) Preparation of complex C3

Add n-BuLi (6mmol) dropwise to the petroleum ether solution of ligand L3 (1.7g, 0.006mol) at 0°C, react overnight, add TiCl ₄ (0.006mol) at -78°C, and react for 12-24h . The solvent was removed, n-hexane was added to wash, and the filtrate was concentrated at low temperature for recrystallization to obtain 350 mg of dark red crystals with a yield of 13%. The molecular structure of C3 is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ=7.75 (d, J=8.8, 1H, Ind-H), 7.69 (d, J=8.8, 1H, Ind-H), 7.44-7.37 (m, 1H, Ind-H) -H), 7.37-7.31 (m, 1H, Ind-H), 7.26-7.24 (m, 1H, thienyl-H), 7.19 (d, J=3.6, 1H, Ind-H), 7.12 (d, J =5.2, 1H, Ind-H), 6.60 (d, J=5.2, 1H, thienyl-H), 3.07-2.99 (m, 1H, (CH ₂ ) ₅ ), 2.80-2.70 (m, 1H, (CH ₂ ) ₅ ), 2.69-2.60 (m, 1H, (CH ₂ ) ₅ ), 2.33-2.07 (m, 3H, (CH ₂ ) ₅ ), 1.90-1.73 (m, 4H, (CH ₂ ) ₅ ), 1.70 (s, 3H, thienyl-CH ₃ ). Anal. Calcd. for C ₂₀ H ₂₁ TiCl ₃ S 0.4 (C ₅ H ₁₂ ): C, 55.45; H, 5.46; found: C, 55.72; H, 5.48% .

Example 4

Preparation of Substituted Indene Titanium Complex C4

(1) Preparation of Ligand Compound L4

At 78°C, 7.1 g (36 mmol) of 6,6-pentylidene benzofulvene was added dropwise to a solution of 5-trimethylsilyl-2-thiophene lithium salt (36 mmol) in 40 mL of ether, and reacted at room temperature for 1 day. After hydrolysis, the organic layer was extracted with 50 mL of petroleum ether, and purified by column chromatography (petroleum ether was used as a developing solvent) to obtain 3.1 g of light yellow solid with a yield of 24%. The structural formula is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.48-7.40 (m, 1H, Ind-H), 7.35-7.27 (m, 1H, Ind-H), 7.17-7.10 (m, 2H, Ind-H), 7.06-7.01(m, 1H, thienyl-H), 6.96-6.90(m, 1H, thienyl-H), 6.42(s, 1H, Ind-H), 3.40(s, 2H), 2.55-2.44(m, 2H, (CH ₂ ) ₅ ), 2.30-2.17 (m, 2H, (CH ₂ ) ₅ ), 1.75-1.45 (m, 6H, (CH ₂ ) ₅ ), 0.28 (s, 9H, thienyl-SiMe ₃ ) .

(2) Preparation of complex C4

Add n-BuLi (3.6mmol) dropwise to ligand L4 (1.3g, 3.6mmol) in 50mL n-hexane solution at 0°C, react overnight, add TiCl ₄ (3.6mmol) at -78°C, react 12 ~24h. The solvent was removed, n-hexane was added to wash, and the filtrate was concentrated at low temperature for recrystallization to obtain 870 mg of dark red crystals with a yield of 48%. The molecular structure of C4 is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.96(d, J=8.8Hz, 1H), 7.71(d, J=8.8Hz, 1H), 7.51-7.44(m, 1H), 7.39-7.32(m, 1H), 7.18(d, J=3.2Hz, 1H), 7.16(d, J=3.2Hz, 1H), 7.09(d, J=3.6Hz, 1H), 6.99(d, J=3.6Hz, 1H) , 2.91(d, J=13.2Hz, 1H), 2.76(td, J=13.2, 3.2Hz, 1H), 2.68-2.58(m, 1H), 2.32-2.18(m, 1H), 1.84-1.64(m , 5H), 1.55-1.45 (m, 1H), 0.25 (s, 9H). Anal. Calcd. for C ₂₂ H ₂₇ Cl ₃ SSiTi 0.8C ₅ H ₁₂ : C, 55.41; H, 6.55; found: C, 55.79; H, 6.35%.

Example 5

Preparation of Substituted Indene Titanium Complex C5

(1) Preparation of Ligand Compound L5

At 78°C, add 9.4g (48mmol) 6,6-pentylidenebenzofulvene dropwise to 40mL ether solution of 2-furyl lithium salt (48mmol), react at room temperature for 1 day, hydrolyze, and use 50mL petroleum ether The organic layer was extracted and purified by column chromatography (petroleum ether as the developing solvent) to obtain 2.3 g of a white solid with a yield of 18%. The structural formula is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.45 (d, J=6.8Hz, 1H, Ind-H), 7.39 (d, J=7.2Hz, 1H, Ind-H), 7.34-7.30 (m, 1H , fury-H), 7.20-7.09 (m, 2H, Ind-H), 6.35-6.28 (m, 2H, Ind-H, fury-H), 6.23-6.20 (m, 1H, fury-H), 3.33 (s, 2H, Ind-H), 2.44-2.35 (m, 2H, (CH ₂ ) ₅ ), 2.20-2.10 (m, 2H, (CH ₂ ) ₅ ), 1.70-1.50 (m, 6H, (CH ₂ ) ₅ ).

(2) Preparation of complex C5

Add n-BuLi (3.6mmol) dropwise to ligand L5 (0.95g, 3.6mmol) in 50mL petroleum ether solution at 0°C, react overnight, add TiCl ₄ (3.6mmol) at -78°C, react 12 ~24h. The solvent was removed, petroleum ether was added to wash, and the filtrate was recrystallized to obtain 810 mg of dark red crystals with a yield of 54%.

The molecular structural formula is as follows:

¹ HNMR (400MHz, CDCl3): δ7.96 (d, J=8.8Hz, 1H, Ind-H), 7.71 (d, J=8.8Hz, 1H, Ind-H), 7.53-7.46 (m, 1H, Ind-H), 7.42-7.33 (m, 2H, Ind-H, fury-H), 7.15 (d, J=3.6Hz, 1H, fury-H), 6.96 (d, J=3.6Hz, 1H, Ind -H), 6.44-6.34(m, 2H, Ind-H, fury-H), 2.91(d, J=13.2Hz, 1H, (CH ₂ ) ₅ ), 2.68(d, J=13.2Hz, 1H, (CH ₂ ) ₅ ), 2.34 (td, J=12.8, 3.6Hz, 1H, (CH ₂ ) ₅ ), 2.14 (td, J=12.8, 3.6Hz, 1H, (CH ₂ ) ₅ ), 1.85-1.65 (m, 3H, (CH ₂ ) ₅ ), 1.62-1.35 (m, 3H, (CH ₂ ) ₅ ). Anal. Calcd. for C ₁₉ H ₁₉ TiCl ₃ O: C, 54.65; H, 4.59; found: C , 54.21; H, 5.10%.

Example 6

Preparation of Substituted Indene Titanium Complex C6

(1) Preparation of Ligand Compound L6

At 78°C, 9.4g (48mmol) of 6,6-pentylidene benzofulvene was added dropwise to 40mL of ether solution of 5-methyl-2-furyl lithium salt (48mmol), reacted at room temperature for 1 day, and hydrolyzed , the organic layer was extracted with 50 mL of petroleum ether, and purified by column chromatography (petroleum ether was used as a developing solvent) to obtain 1.1 g of a white solid with a yield of 8%. The structural formula is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ7.52-7.40 (m, 2H, Ind-H), 7.22-7.10 (m, 2H, Ind-H), 6.30 (s, 1H, Ind-H), 6.07 ( s, 1H, fury-H), 5.90 (s, 1H, fury-H), 3.34 (s, 2H, Ind-H), 2.45-2.35 (m, 2H, (CH ₂ ) ₅ ), 2.30-2.20 ( m, 3H, fury-CH ₃ ), 2.19-2.09 (m, 2H, (CH ₂ ) ₅ ), 1.73-1.38 (m, 6H, (CH ₂ ) ₅ ).

(2) Preparation of complex C6

Add n-BuLi (3.6mmol) dropwise to ligand L6 (1.0g, 3.6mmol) in 50mL petroleum ether solution at 0°C, react overnight, add TiCl ₄ (3.6mmol) at -78°C, react 12 ~24h. The solvent was removed, petroleum ether was added to wash, and the filtrate was recrystallized to obtain 650 mg of dark red crystals with a yield of 42%. The molecular structure of C6 is as follows:

¹ HNMR (400MHz, CDCl ₃ ): δ8.02 (d, J=8.8Hz, 1H, Ind-H), 7.71 (d, J=8.8Hz, 1H, Ind-H), 7.56-7.46 (m, 1H , Ind-H), 7.44-7.33 (m, 1H, Ind-H), 7.15 (d, J=3.6Hz, 1H, fury-H), 7.00 (d, J=3.6Hz, 1H, Ind-H) , 6.25(d, J=2.4Hz, 1H, fury-H), 5.94(d, J=2.4Hz, 1H, Ind-H), 2.89(d, J=13.2Hz, 1H, (CH ₂ ) ₅ ) , 2.65(d, J=13.2Hz, 1H, (CH ₂ ) ₅ ), 2.32-2.16(m, 4H, (CH ₂ ) ₅ , fury-CH ₃ ), 2.11(td, J=13.2, 3.6Hz, 1H, (CH ₂ ) ₅ ), 1.81-1.64 (m, 3H, (CH ₂ ) ₅ ), 1.63-1.37 (m, 3H, (CH ₂ ) ₅ ). Anal. Calcd. for C ₂₀ H ₂₁ Cl ₃ OTi 0.3(C ₅ H ₁₂ ): C, 56.97; H, 5.47; found: C, 57.59; H, 5.42%.

Example 7

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C1 catalyst at 0 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, and react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract the supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 20kg/(mol-Ti h), and the selectivity of 1-hexene is greater than 98%.

Example 8

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C1 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 8 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g of n-heptane as an internal standard, extract the supernatant for gas chromatography, and calculate the catalytic activity for generating 1-hexene to be 77kg/(mol-Ti·h), and the selectivity of 1-hexene to be 89%.

Example 9

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C1 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 8 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract the supernatant liquid for gas chromatography, calculate the catalytic activity of generating 1-hexene to be 107kg/(mol-Ti·h), and the selectivity of 1-hexene is 79%.

Example 10

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C1 catalyst at 80 ° C, add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as an internal standard, extract the supernatant liquid for gas chromatography, and calculate the catalytic activity of generating 1-hexene to be 161kg/(mol-Ti·h), and the selectivity of 1-hexene is 88%.

Example 11

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C2 catalyst at 0 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 112kg/(mol-Ti h), and the selectivity of 1-hexene is greater than 98%.

Example 12

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C2 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract the supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 413kg/(mol-Ti·h), and the selectivity of 1-hexene is 97%.

Example 13

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C2 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 8 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g of n-heptane as an internal standard, extract the supernatant for gas chromatography, and calculate the catalytic activity of generating 1-hexene to be 476kg/(mol-Ti·h), and the selectivity of 1-hexene is 94%.

Example 14

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C2 catalyst at 80 ° C, add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 697kg/(mol-Ti·h), and the selectivity of 1-hexene is 95%.

Example 15

Add 20 mL of toluene into a 50 mL autoclave, add 1.5 μmol of C3 catalyst at 0°C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 11kg/(mol-Ti h), and the selectivity of 1-hexene is greater than 98%.

Example 16

Add 20 mL of toluene into a 50 mL autoclave, add 1.5 μmol of C3 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g of n-heptane as an internal standard, extract the supernatant for gas chromatography, calculate the catalytic activity to generate 1-hexene is 20kg/(mol-Ti·h), and the selectivity of 1-hexene is 68%.

Example 17

Add 20 mL of toluene into a 50 mL autoclave, add 1.5 μmol of C3 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 8 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as an internal standard, extract the supernatant liquid for gas chromatography, calculate the catalytic activity to generate 1-hexene is 27kg/(mol-Ti·h), and the selectivity of 1-hexene is 67%.

Example 18

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C3 catalyst at 80 ° C, add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g of n-heptane as an internal standard, extract the supernatant for gas chromatography, and calculate the catalytic activity for generating 1-hexene to be 51kg/(mol-Ti·h), and the selectivity of 1-hexene to be 32%.

Example 19

Add 20mL of toluene to a 50mL autoclave, add 1.5μmol of C4 catalyst at 0°C, add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5atm, react for 30 minutes, open the autoclave, and add 1mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 53kg/(mol-Ti·h), and the selectivity of 1-hexene is greater than 98%.

Example 20

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C4 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 328kg/(mol-Ti·h), and the selectivity of 1-hexene is 94%.

Example 21

Add 20mL of toluene to a 50mL autoclave, add 1.5μmol of C4 catalyst at 0°C, add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 8atm, and react for 30 minutes, open the autoclave, and add 1mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as an internal standard, extract the supernatant liquid for gas chromatography, calculate the catalytic activity of generating 1-hexene to be 448kg/(mol-Ti·h), and the selectivity of 1-hexene is 82%.

Example 22

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C4 catalyst at 80 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as an internal standard, extract the supernatant liquid for gas chromatography, and calculate the catalytic activity of generating 1-hexene to be 403kg/(mol-Ti·h), and the selectivity of 1-hexene is 66%. Ethanol containing 5% HCl was added to the reaction solution, the precipitate was collected, washed until neutral, dried and weighed to obtain 158 mg of polyethylene with a catalytic activity of 210 kg/(mol-Ti·h).

Example 23

Add 20mL of toluene to a 50mL autoclave, add 1.5μmol of C5 catalyst at 30°C, adjust the polymerization pressure to 5atm, and react for 30 minutes, then add 1mL of ethanol to the reaction mixture to terminate the reaction. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 3kg/(mol-Ti·h), and the selectivity of 1-hexene is less than 10%. Ethanol containing 5% HCl was added to the reaction solution, the precipitate was collected, washed until neutral, dried and weighed to obtain 59 mg of polyethylene with a catalytic activity of 78 kg/(mol-Ti·h).

Example 24

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C5 catalyst at 80 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to terminate. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 8kg/(mol-Ti·h), and the selectivity of 1-hexene is less than 10%. Ethanol containing 5% HCl was added to the reaction solution, the precipitate was collected, washed until neutral, dried and weighed to obtain 62 mg of polyethylene with a catalytic activity of 82 kg/(mol-Ti·h).

Example 25

Add 20 mL of toluene into a 50 mL autoclave, add 1.5 μmol of C6 catalyst at 30 ° C, and add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to stop. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 4kg/(mol-Ti·h), and the selectivity of 1-hexene is less than 10%. Ethanol containing 5% HCl was added to the reaction solution, the precipitate was collected, washed until neutral, dried and weighed to obtain 140 mg of polyethylene with a catalytic activity of 186 kg/(mol-Ti·h).

Example 26

Add 20 mL of toluene to a 50 mL autoclave, add 1.5 μmol of C6 catalyst at 80 ° C, add MAO according to the aluminum-titanium ratio of 1000, adjust the polymerization pressure to 5 atm, react for 30 minutes, open the autoclave, and add 1 mL of ethanol to the reaction mixture to stop. Add 0.068g n-heptane as internal standard, extract supernatant liquid and do gas chromatography, calculate the catalytic activity of generating 1-hexene to be 11kg/(mol-Ti·h), and the selectivity of 1-hexene is less than 10%. Ethanol containing 5% HCl was added to the reaction solution, the precipitate was collected, washed until neutral, dried and weighed to obtain 222 mg of polyethylene with a catalytic activity of 296 kg/(mol-Ti·h).

Claims (6)

1. a catalyst of ethylene trimerization, is characterized in that having following general structure:

In formula (I), R ¹and R ²for identical or different C ₁~ C ₆the alkyl of straight chain, branched structure, or to be connected the C formed by both ₄~ C ₇cyclic alkyl; R ³~ R ⁴for hydrogen; R ⁵for C ₁~ C ₆the alkyl of straight chain, branched structure or silylation; X is chlorine; Y is sulphur.

2. catalyzer according to claim 1, is characterized in that, R ¹and R ²for the cyclohexyl be made up of both; R ⁵for methyl or trimethylsilyl.

3. the preparation method of catalyzer described in any one of claim 1-2, comprises the steps:

Under protection of inert gas, the pendency fragrant heterocyclic radical replacement indenyl ligand shown in formula (II) and alkali alkyl compound are reacted in organic solvent, generates an alkali metal salt that pendency fragrant heterocyclic radical replaces indenyl ligand, add a certain amount of TiCl afterwards ₄react with this alkali metal salt, drain solvent, after remaining solid is washed with organic solvent, dissolving, filter, filtrate is carried out recrystallization and obtains final catalyst product:

In formula (II), R ¹and R ²for identical or different C ₁~ C ₆the alkyl of straight chain, branched structure, or to be connected the C formed by both ₄~ C ₇cyclic alkyl; R ³~ R ⁴for hydrogen; R ⁵for C ₁~ C ₆the alkyl of straight chain, branched structure or silylation; Y is sulphur;

Described alkali alkyl compound is selected from C ₁~ C ₄lithium alkylide;

Temperature of reaction is-78 ~ 25 DEG C, and the reaction times is 2 ~ 48h.

4. method according to claim 3, is characterized in that, described alkali alkyl compound is butyllithium;

The mol ratio that pendency fragrant heterocyclic radical replaces indenyl ligand and alkali alkyl compound is: 1: 1 ~ 1.25;

Pendency fragrant heterocyclic radical replaces an alkali metal salt and the TiCl of indenyl ligand ₄mol ratio be: 1: 1 ~ 1.25.

5. method according to claim 3, is characterized in that, described organic solvent is selected from one or more in tetrahydrofuran (THF), ether, toluene, benzene, chloroform, methylene dichloride and sherwood oil.

6. the application of catalyzer described in any one of claim 1 ~ 2, is characterized in that, for ethylene trimerization.