A single metallocene compound and its preparation method and application

Abstract

The present invention relates to a single metallocene compound, which is a 1,3-di(aryl / alkyl) five-membered ring diazaboryloxy single metallocene compound Cp'(L)MR 1 2, whose structural formula is shown in formula (I), wherein M is titanium, zirconium or hafnium; Cp' is selected from one of a hydrocarbon-substituted or unsubstituted cyclopentadienyl group, a hydrocarbon-substituted or unsubstituted indenyl group, and a hydrocarbon-substituted or unsubstituted fluorenyl group; R 1 is selected from a halogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, and a hydrocarbon-substituted or unsubstituted benzyl group; R 2 The present invention also relates to a method for preparing the monometallocene compound. The boron-oxygen electron-donating structure and the large steric hindrance of the substituents in the monometallocene compound provide excellent stability to the catalytic active center, allowing the molecular weight of the polymer to be controlled.

Description

Technical Field

[0001] The present invention relates to a preparation method and application of an organic titanium / zirconium / hafnium compound, and in particular to a preparation method of a 1,3-di(aryl / alkyl) five-membered ring diazaboryloxymonocene Group IV metal compound and its application in the copolymerization of ethylene and norbornene. Background Art

[0002] The design of highly efficient molecular catalysts for olefin polymerization has long garnered widespread attention in fields such as organometallic chemistry, catalysis, and polymer chemistry. Semititanocene compounds (CpOTiX2(Y)) containing anionic electron-donating ligands (Cp cyclopentadienyl, X halogen, alkyl, Y aryloxy, ketimine, phosphinimine, etc.) have demonstrated high catalytic activity and controllability in the copolymerization of ethylene to novel polymers, such as styrene, norbornene (NBE), or other cycloolefins.

[0003] Polyolefins have been widely used in our daily lives, and various high-performance polymer products have been widely used in our daily lives. Among them, some cyclic olefin copolymers (COC) are amorphous materials with high transparency in the UV-vis region, as well as humidity and heat resistance and high glass transition temperature (T g ) is a promising combination. Generally, the actual production of COC involves three processes, such as (1) ring-opening, metathesis polymerization of polycyclic olefins and subsequent hydrogenation, (2) coordination copolymerization of ethylene and cycloolefins, and (3) homopolymerization of cycloolefins. In particular, copolymerization can control the polymer ratio and microstructure characteristics, making the properties of polymer materials controllable and variable. Therefore, a variety of compounds are used to catalyze the copolymerization of ethylene and NBE, such as metallocenes, linked semi-titanocenes (so-called constrained geometry types), non-bridged semi-titanocenes and other so-called non-metallocenes. These COC materials are commercialized using metallocene catalysts (such as TOPASVR) as ultra-pure (suitable for advanced pharmaceutical packaging and food contact films), crystal clear (glass-transparent and amorphous) and high barrier (humidity, alcohol and acid resistance) materials. However, successful examples of effectively synthesizing random, high molecular weight copolymers with high NBE content (>50 mol%) are still limited. COC materials have been commercialized in the fields of advanced optics, medical devices, containers and packaging and have broad development prospects. They have developed rapidly in recent years and shown strong momentum.

[0004] The advent of metallocene catalysis has significantly advanced the development of the polyolefin industry, as its unique steric and electronic structures endow it with exceptional catalytic performance. In recent years, non-metallocene catalytic systems have garnered significant attention due to their versatile and controllable architecture and simple synthesis. These systems now play a key role in the search for novel, highly efficient olefin polymerization catalysts. Among other systems, CpTi(L)X2-type monocyclopentadienyl metal complexes containing an additional monoanionic auxiliary ligand, L, represent an important class of precatalysts for olefin homopolymerization and copolymerization. They exhibit high catalytic activity in ethylene polymerization, particularly with other olefins, such as long-chain terminal olefins and cycloolefins. Typical ligands, L, include π donors such as aryl oxides, ketimides, phosphoramides, and guanidinium salts. Due to their ability to act as 2σ,4π electron donors, they can be considered monodentate analogs of the cyclopentadienyl C5R5 group. CpTi(L)X2-type monocyclopentadienyl ligands are mainly divided into two categories: aryloxy monoanion electron donors and imine electron donor ligands. Aryloxy electron donor ligands have been widely studied in catalyzing the polymerization of ethylene and norbornene. Nomura reported an aryloxy electron donor complex containing an electron-withdrawing group on the aryl group, which showed excellent catalytic performance in catalyzing the copolymerization of ethylene and norbornene (Organometallics, 2016: 1895-1905.). It is generally believed that the stronger the electron-donating ability of the ligand, the higher the catalytic activity of the compound. However, this type of aryloxy monotitanocene compound containing electron-withdrawing substituents exhibits more efficient catalytic behavior than its electron-donating analogues. Kretschmer and Hessen reported an imidazolidinidine-imine electron donor complex (Chemical Communications, 2002, 114(6): 608-609.) as a catalyst precursor for catalyzing olefin polymerization. Under the condition of B(C6F5)3 as a co-catalyst, the compound showed high catalytic activity in catalyzing ethylene homopolymerization, even higher than its acyl ketimine electron donor analogues and phosphoimine electron donor analogues. Summary of the Invention

[0005] The object of the present invention is to provide a monometallocene compound, which is composed of an electron-donating ligand borane ligand coordinated with a non-bridged monometallocene Group IV metal compound. The borane ligand has a special electronic structure and steric hindrance, so that the monometallocene compound has high activity and good thermal stability in the copolymerization of ethylene and cycloolefins.

[0006] To this end, the present invention provides a single metallocene compound, which is a 1,3-di(aryl / alkyl) five-membered ring diazaboryloxy single metallocene compound Cp'(L)MR 1 2, whose structural formula is shown in formula (I):

[0007]

[0008] Wherein, M is titanium, zirconium or hafnium; Cp' is selected from one of a hydrocarbon-substituted or unsubstituted cyclopentadienyl group, a hydrocarbon-substituted or unsubstituted indenyl group, and a hydrocarbon-substituted or unsubstituted fluorenyl group; R is selected from one of a C1-C10 alkyl group and a C6-C12 aromatic group; R 1 is selected from a halogen atom, a C1-C10 alkyl group, a C1-C10 alkoxy group, and a hydrocarbon-substituted or unsubstituted benzyl group; R 2 One selected from hydrogen and C1-C10 alkyl.

[0009] The monometallocene compound of the present invention is preferably selected from the group consisting of a hydrocarbon-substituted or unsubstituted cyclopentadienyl group, a hydrocarbon-substituted or unsubstituted indenyl group, and a hydrocarbon-substituted or unsubstituted fluorenyl group; R is selected from the group consisting of a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a 2,6-dimethylphenyl group, a 2,6-diisopropylphenyl group, and a 2,4,6-trimethylphenyl group; and R 1 is selected from one of chlorine, fluorine, methyl, ethyl, isopropyl, methoxy, and benzyl; R 2 One selected from hydrogen and methyl.

[0010] The single metallocene compound of the present invention is preferably any one of the following:

[0011] C1: Cp'Ti(L)Cl2, Cp'=cyclopentadienyl, R=2,6-diisopropylphenyl, R 2 =H;

[0012] C2: Cp'Ti(L)Cl2, Cp' = pentamethylcyclopentadienyl, R = 2,6-diisopropylphenyl, R 2 =H;

[0013] C3: Cp'Ti(L)Cl2, Cp'=cyclopentadienyl, R=2,6-dimethylphenyl, R 2 =H;

[0014] C4: Cp'Zr(L)Cl2, Cp'=cyclopentadienyl, R=2,6-diisopropylphenyl, R 2 =H;

[0015] C5: Cp'Ti(L)Me2, Cp'=cyclopentadienyl, R=2,6-diisopropylphenyl, R 2 =H.

[0016] To this end, the present invention also provides a method for preparing a single metallocene compound, comprising the following steps:

[0017] (1) Under an argon atmosphere, a borane ligand 1,3-di(aryl / alkyl) five-membered ring diazaborane hydroxy compound and sodium hydride are dissolved in a good solvent and reacted at 20-40°C for the first time, a metal ligand Cp'MX3 is added at -78-80°C, and a second reaction is continued in a good solvent at 20-40°C. After removing the good solvent, a poor solvent is added to settle the mixture, filtered, and then the poor solvent is removed to obtain the monometallocene halide, the general structural formula of which is shown in Formula (I):

[0018]

[0019] Wherein, M is titanium, zirconium or hafnium; X is selected from one of halogen atoms; Cp' is selected from one of hydrocarbon-substituted or unsubstituted cyclopentadienyl, hydrocarbon-substituted or unsubstituted indenyl, and hydrocarbon-substituted or unsubstituted fluorenyl; R is selected from one of C1-C10 alkyl and C6-C12 aromatic groups; R 1 One selected from halogen atoms; R 2 One selected from hydrogen and C1-C10 alkyl.

[0020] To this end, the present invention also provides a method for preparing a single metallocene compound, comprising the following steps:

[0021] (1) Under an argon atmosphere, a borane ligand 1,3-di(aryl / alkyl) five-membered ring diazaboryl hydroxy compound and sodium hydride are dissolved in a good solvent and reacted at 20-40°C for the first time, a metal ligand Cp'MX3 is added at -78-80°C, and a second reaction is continued in a good solvent at 20-40°C. After removing the good solvent, a poor solvent is added to settle the mixture, and then filtered, and the poor solvent is removed to obtain an intermediate product 1,3-di(aryl / alkyl) five-membered ring diazaboryloxy monometallocene chloride;

[0022] (2) The intermediate product is mixed with a Grignard reagent under an argon atmosphere, and the mixture is reacted for a third time in an anhydrous solvent at 20-40° C. The anhydrous solvent is removed, a poor solvent is added, the mixture is precipitated, and then filtered. The poor solvent is then removed to obtain the monometallocene compound, the general structural formula of which is shown in Formula (I):

[0023]

[0024] Wherein, M is titanium, zirconium or hafnium; X is selected from one of halogen atoms; Cp' is selected from one of hydrocarbon-substituted or unsubstituted cyclopentadienyl, hydrocarbon-substituted or unsubstituted indenyl, and hydrocarbon-substituted or unsubstituted fluorenyl; R is selected from one of C1-C10 alkyl and C6-C12 aromatic groups; R 1 One selected from C1-C10 alkyl, C1-C10 alkoxy, hydrocarbon-substituted or unsubstituted benzyl; R 2One selected from hydrogen and C1-C10 alkyl.

[0025] The preparation method of the present invention is preferably such that the proportions of the components in step (1) are as follows: based on 1 mmol of monocyclopentadienyl ligand, the amount of sodium hydride is 1-3 mmol, more preferably 1.5-2 mmol, the amount of the good solvent is 10-30 mL, more preferably 15-25 mL, and the amount of the poor solvent is 10-30 mL, more preferably 15-25 mL.

[0026] In the preparation method of the present invention, preferably, the molar ratio of the borane ligand 1,3-di(aryl / alkyl) five-membered ring diazaborane hydroxy compound to the metal ligand Cp'MX3 is 1:0.8-1.5, more preferably 1:1.0-1.2.

[0027] In the preparation method of the present invention, preferably, the time of the first reaction is 10 to 18 hours, more preferably 12 to 16 hours; the temperature for adding the metal ligand is 20 to 60°C; and the conditions for the secondary reaction are 10 to 18 hours, more preferably 12 to 16 hours.

[0028] In the preparation method of the present invention, preferably, the good solvent is selected from one of diethyl ether and tetrahydrofuran, more preferably diethyl ether; and the poor solvent is selected from one of n-hexane, n-pentane, n-heptane and cyclohexane, more preferably n-hexane.

[0029] In the preparation method of the present invention, it is preferred that in step (2), the anhydrous solvent is selected from one of benzene, toluene, xylene, n-hexane, n-pentane, n-heptane, cyclohexane, and tetrahydrofuran; more preferably, toluene.

[0030] The preparation method of the present invention is preferably that, in step (2), the molar ratio of the intermediate product to the Grignard reagent is 0.8 to 1.2:3, more preferably 1.0 to 1.2:3; based on 1 mmol of the borane ligand, the amount of the good solvent is 10 to 30 mL, more preferably 15 to 25 mL; the amount of the anhydrous solvent is 10 to 30 mL, more preferably 15 to 25 mL.

[0031] To this end, the present invention also provides an application of the above-mentioned single metallocene compound for catalyzing the copolymerization of ethylene with propylene, 1-octene, cyclobutene, cyclopentene, norbornene or 1,4,5,8-dimethyl-1,2,3,4,4a,5,8,8a-octahydronaphthalene (DMON), preferably the copolymerization of ethylene and norbornene.

[0032] The application of the single metallocene compound described in the present invention is preferably to use the above-mentioned single metallocene compound as a catalyst precursor and methylaluminoxane MAO as a co-catalyst to catalyze the polymerization of ethylene and norbornene at 0-100°C, more preferably 60-80°C. During the polymerization, the molar ratio of the catalyst precursor to methylaluminoxane MAO is 1:50-2000, more preferably 1:400-1200, and the molar ratio of the catalyst precursor to norbornene is 1:50-10000, more preferably 1:1500-5000; the polymerization time is 1-60 minutes, more preferably 10-30 minutes; the polymerization solvent is selected from one of benzene, toluene, n-hexane, tetrahydrofuran and dichloromethane, more preferably toluene.

[0033] Specifically, the preparation method of the above-mentioned compound of the present invention comprises the following steps:

[0034] (1) Under argon atmosphere, 1,3-di(aryl / alkyl) five-membered ring diazaboryl hydroxy compound (synthesized by literature method, Journal of the American Chemical Society, 2008, 130(47): 16069-16079.) and sodium hydride are dissolved in 10-30 mL of anhydrous solvent (preferably 15-25 mL), and reacted in good solvent ether at room temperature for 10-18 hours (preferably 12-16 hours). 0.8-1.5 equivalents (preferably 1.0-1.2 equivalents) of Cp'TiCl3 are added at -78°C, and reacted in ether solvent at room temperature for 10-18 hours (preferably 12-16 hours). The ether solvent is removed under reduced pressure, and the compound is added to 10-30 mL of anhydrous solvent (preferably 15-25 mL) of poor solvent n-hexane for precipitation and then filtered. The n-hexane solvent is removed under reduced pressure to obtain 1,3-di(aryl / alkyl) five-membered ring diazaboryl oxymonocene titanium chloride. (This corresponds to R in the general formula (I) 1 for halogen atoms)

[0035] (2) Under an argon atmosphere, the ligand metal chloride and the Grignard reagent are mixed in a molar ratio of 0.8 to 1.2:3 (preferably 1.0 to 1.2:3), and reacted in an ether solvent at room temperature for 10 to 18 hours (preferably 12 to 16 hours). The ether solvent is removed under reduced pressure, and the mixture is added to 10 to 30 mL of anhydrous toluene (preferably 15 to 25 mL) for precipitation and then filtered. The toluene solvent is removed under reduced pressure to obtain the corresponding metal alkyl. (This corresponds to R in the general formula (I) 1 (C1-C10 alkyl, C1-C10 alkoxy, hydrocarbon-substituted or unsubstituted benzyl)

[0036] The beneficial effects of the present invention are as follows:

[0037] (1) The single metallocene compound provided by the present invention is composed of a borane ligand 1,3-di(aryl / alkyl) five-membered ring diazaborane hydroxy compound and a metal ligand. The borane electron donor structure and the large substituent steric hindrance make the catalytic active center of the single metallocene compound have good stability when used to catalyze the copolymerization of ethylene and cycloolefins, and can regulate the molecular weight of the polymer and the norbornene content in the polymer.

[0038] (2) The single metallocene compound provided by the present invention is easy to prepare, low in cost, stable in properties, and has high catalytic activity, providing a new system for COC polymer catalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is the accompanying hydrogen nuclear magnetic resonance spectrum of Example 1 (Compound C1).

[0040] Figure 2 Attached is the carbon NMR spectrum of Example 1 (Compound C1).

[0041] Figure 3 This is the accompanying hydrogen nuclear magnetic resonance spectrum of Example 2 (Compound C2).

[0042] Figure 4 Attached is the carbon NMR spectrum of Example 2 (Compound C2). DETAILED DESCRIPTION

[0043] The following examples of the present invention are described in detail. These examples are based on the technical solutions of the present invention and provide detailed implementation methods and processes. However, the scope of protection of the present invention is not limited to the following examples. Experimental methods in the following examples where specific conditions are not specified are generally based on conventional conditions. Materials, reagents, etc. used in the following examples are all commercially available unless otherwise specified.

[0044] In the following examples, L = 1,3-di(aryl / alkyl) five-membered ring diazaboryloxy.

[0045] Example 1

[0046] Preparation of compound C1 (CpTi(L)Cl2)

[0047] Under argon atmosphere, the monocyclopentadienyl ligand 1,3-bis(2,6-diisopropylphenyl) pentacyclic diazaboryl hydroxy compound (0.484 g, 1 mmol) and sodium hydride (0.48 g, 2 mmol) were dissolved in 20 mL of anhydrous ether and reacted at room temperature for 18 h. 0.218 mg (0.218 g, 1 mmol) of the metal ligand CpTiCl3 (Cp = cyclopentadienyl) was added at -78 °C and reacted at room temperature for 12 h. The ether solvent was removed under reduced pressure, 15 mL of n-hexane was added for extraction, the mixture was filtered and the solvent n-hexane was removed under reduced pressure to obtain 427 mg of a red solid (0.73 mmol) with a yield of 73.0 wt%.

[0048] 1 H NMR(C6D6): δ7.20-7.14(m,6H,Ar-H),5.88(s,2H,N-CH),5.82(s,5H,Ti-CH),3.31(m, 4H, J=6.7Hz, CH3-CH), 1.39 (d, 12H, J=6.6Hz, CH-CH3), 1.21 (d, 12H, J=6.8Hz, CH-CH3). 13 C NMR (C6D6): δ146.55,137.94,123.77,119.93,116.48,28.97,24.82,23.92.

[0049] Example 2

[0050] Preparation of compound C2(Cp*Ti(L)Cl2)

[0051] The experimental steps were the same as those in Example 1, except that the metal ligand was replaced with Cp*TiCl3, Cp*=pentamethylcyclopentadienyl, and finally 389 mg of black solid was obtained, 0.59 mmol, with a yield of 59.0 wt%.

[0052] 1 H NMR (C6D6): δ7.24-7.18(m,6H,Ar-H),5.90(s,2H,N-CH),3.31(m,4H,J=6.7Hz,CH3-CH),1.90(s,15H,C5-Me5),1.25(t,24H,J=7.4Hz,CH-CH3). 13 C NMR (C6D6): δ146.55,137.94,123.77,119.93,116.48,28.97,24.82,23.92.

[0053] Example 3

[0054] Preparation of compound C3 (CpTi(L)Cl2)

[0055] The experimental steps were the same as those in Example 1, except that the R substituent in the ligand L was replaced with 2,4,6-trimethylphenyl. The final yield of compound C3 (CpTi(L)Cl2) was 326 mg, 0.69 mmol, and 69 wt%.

[0056] 1 H NMR(C6D6): δ7.24-7.19(m,6H,Ar-H),5.72(s,2H,N-CH),5.73(s,5H,Ti-CH),1.16(s,12H,CH-CH3). 13 C NMR(C6D6): δ147.32,135.64,128.50,117.55,116.23,27.34.

[0057] Example 4

[0058] Preparation of compound C4 (CpZr(L)Cl2)

[0059] The experimental steps were the same as those in Example 1, except that the metal ligand was replaced by CpZrCl3, Cp=cyclopentadienyl, and the final compound C4 (CpZr(L)Cl2) had a yield of 469 mg, 0.75 mmol, and 75 wt%.

[0060] 1 H NMR(C6D6): δ7.25-7.18(m,6H,Ar-H),5.74(s,2H,N-CH),5.84(s,5H,Zr-CH),3.38(m, 4H, J=6.8Hz, CH3-CH), 1.43 (d, 12H, J=6.7Hz, CH-CH3), 1.28 (d, 12H, J=6.8Hz, CH-CH3). 13 C NMR (C6D6): δ147.88,137.64,125.89,117.21,116.79,25.34,23.20,21.56.

[0061] Example 5

[0062] Preparation of compound C5 (CpTi(L)Me2)

[0063] Under argon atmosphere, compound C1 (CpTi(L)Cl2) (0.585 g, 1 mmol) prepared in Example 1 was dissolved in 20 mL of anhydrous toluene, and 0.66 mL (2 mmol) of methylmagnesium bromide was added dropwise. The reaction was carried out at room temperature for 18 h. After the toluene was drained, 15 mL of n-hexane was added for extraction. The product was concentrated and crystallized to obtain 419 mg of a red solid, 0.67 mmol, with a yield of 66.5 wt%.

[0064] 1 H NMR(C6D6): δ7.32-7.21(m,6H,Ar-H),5.69(s,2H,N-CH),5.85(s,5H,Ti-CH),3.27(m,4H,J=6.8H z, CH3-CH), 1.64 (s, 6H, Ti-CH3), 1.37 (d, 12H, J=6.7Hz, CH-CH3), 1.25 (d, 12H, J=6.8Hz, CH-CH3).

[0065] Example 6

[0066] Compound C1 prepared in Example 1 and MAO catalyzed ethylene-norbornene copolymerization

[0067] In a Schlenk flask, under anhydrous and oxygen-free conditions, 1.41 g of norbornene, 232 mg of MAO, and 22 mL of anhydrous toluene were added, ethylene gas was introduced, the pressure was maintained at 0.1 MPa, and the temperature was controlled at 60°C. 0.1 μmol of compound C1 (0.059 mg) was dissolved in 3 mL of anhydrous toluene and added to the Schlenk flask with a syringe to catalyze polymerization. The ethylene gas pressure was adjusted to 0.4 MPa and the reaction was carried out for 10 minutes. The mixture was poured into a mixture of ethanol and hydrochloric acid to precipitate the polymer. After filtration, vacuum drying was performed for 12 hours to obtain an ethylene-norbornene copolymer with an activity of 7320 kg (poly) mol -1 (Ti)h -1 .

[0068] Example 7

[0069] Compound C2 prepared in Example 2 and MAO catalyzed ethylene-norbornene copolymerization

[0070] In a Schlenk flask, under anhydrous and oxygen-free conditions, 1.41 g of norbornene, 232 mg of MAO, and 22 mL of anhydrous toluene were added, ethylene gas was introduced, the pressure was maintained at 0.1 MPa, and the temperature was controlled at 60°C. 0.1 μmol of complex C2 (0.066 mg) was dissolved in 3 mL of anhydrous toluene and added to the Schlenk flask with a syringe to catalyze polymerization. The reaction lasted for 10 minutes, and the mixture was poured into a mixture of ethanol and hydrochloric acid to precipitate the polymer. After filtration, the mixture was vacuum-dried for 12 hours to obtain an ethylene-norbornene copolymer with an activity of 6880 kg (poly) mol -1 (Ti)h -1 .

[0071] Example 8

[0072] Compound C3 prepared in Example 3 and MAO catalyzed ethylene-norbornene copolymerization

[0073] In a Schlenk flask, under anhydrous and oxygen-free conditions, 1.41 g norbornene, 232 mg MAO, and 22 mL anhydrous toluene were added, ethylene gas was introduced, the pressure was maintained at 0.1 MPa, and the temperature was controlled at 60°C. 0.1 μmol of complex C3 (0.047 mg) was dissolved in 3 mL anhydrous toluene and added to the Schlenk flask with a syringe to catalyze polymerization. The reaction lasted for 10 minutes, and the mixture was poured into a mixture of ethanol and hydrochloric acid to precipitate the polymer. After filtration, the polymer was vacuum dried for 12 hours to obtain an ethylene-norbornene copolymer with an activity of 9560 kg (poly) mol -1 (Ti)h -1 .

[0074] Example 9

[0075] Compound C4 prepared in Example 4 and MAO catalyzed ethylene-norbornene copolymerization

[0076] In a Schlenk flask, under anhydrous and oxygen-free conditions, 1.41 g of norbornene, 232 mg of MAO, and 22 mL of anhydrous toluene were added, ethylene gas was introduced, the pressure was maintained at 0.1 MPa, and the temperature was controlled at 60°C. 0.1 μmol of complex C4 (0.063 mg) was dissolved in 3 mL of anhydrous toluene and added to the Schlenk flask with a syringe to catalyze polymerization. The reaction lasted for 10 minutes, and the mixture was poured into a mixture of ethanol and hydrochloric acid to precipitate the polymer. After filtration, the polymer was vacuum dried for 12 hours to obtain an ethylene-norbornene copolymer with an activity of 10730 kg (poly) mol -1 (Ti)h -1 .

[0077] Example 10

[0078] Compound C5 prepared in Example 5 and MAO catalyzed ethylene-norbornene copolymerization

[0079] In a Schlenk flask, under anhydrous and oxygen-free conditions, 1.41 g of norbornene, 232 mg of MAO, and 22 mL of anhydrous toluene were added, ethylene gas was introduced, the pressure was maintained at 0.1 MPa, and the temperature was controlled at 60°C. 0.1 μmol of complex C5 (0.055 mg) was dissolved in 3 mL of anhydrous toluene and added to the Schlenk flask with a syringe to catalyze polymerization. The reaction lasted for 10 minutes, and the mixture was poured into a mixture of ethanol and hydrochloric acid to precipitate the polymer. After filtration, vacuum drying was performed for 12 hours to obtain an ethylene-norbornene copolymer with an activity of 9850 kg (poly) mol -1 (Ti)h -1 .

[0080] Comparative Example 1

[0081] CpTi(O-Dipp)Cl2 and MAO catalyzed ethylene-norbornene copolymerization (Chemical Communications, 2006(25):2659-2661.) In a Schlenk flask, under anhydrous and oxygen-free conditions, 1.41 g of norbornene, 232 mg of MAO, and 22 mL of anhydrous toluene were added, ethylene gas was introduced, the pressure was maintained at 0.1 MPa, and the temperature was controlled at 60°C. 0.2 μmol of the complex Flu-CGC (0.094 mg) was dissolved in 3 mL of anhydrous toluene and added to the Schlenk flask with a syringe to catalyze the polymerization. The reaction was carried out for 10 minutes, and the mixture was poured into a mixture of ethanol and hydrochloric acid to precipitate the polymer. After filtration, the polymer was vacuum dried for 12 hours to obtain an ethylene-norbornene copolymer with an activity of 6540 kg (poly) mol -1 (Ti)h -1 .

[0082] Table 1

[0083]

[0084] In Table 1, Al / Ti = 1000 / 1, solvent = toluene, volume = 25 mL, polymerization temperature = 60°C, ethylene pressure = 0.1 MPa, and activity units are kg(poly)mol-1(Ti)h -1 .

[0085] As shown in Table 1, the single metallocene compound provided by the present invention is easy to prepare, low in cost, stable in properties, and has high catalytic activity, with the highest activity reaching 10730 kg (poly) mol -1 (Ti)h -1 , which is about twice the activity of the CpTi(O-Dipp)Cl2 compound in Comparative Example 1, providing a new system for COC polymer catalysts. In addition, the boron-oxygen electron donor structure and the large substituent steric hindrance make the catalytic active center have good stability, which can regulate the molecular weight of the polymer and the norbornene content of the polymer.

[0086] See also Figures 1 to 4 The structure of the compound was characterized by hydrogen and carbon nuclear magnetic resonance spectroscopy. The boron-oxygen ligand in the single metallocene compound provided by the present invention has a special electronic structure and steric hindrance, and the prepared single metallocene compound has stable properties.

[0087] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the present invention.

Claims

1. A single metallocene compound, characterized in that The structural formula of the single metallocene compound is shown in formula (I): （I） Wherein, the single metallocene compound is any one of the following: Cp'Ti(L)Cl2, where Cp' = cyclopentadienyl, R = 2, 6-diisopropylphenyl, R 1 = Cl, R 2 = H, M = Ti; Cp'Ti(L)Cl2, where Cp' = pentamethylcyclopentadienyl, R = 2, 6-diisopropylphenyl, R 1 = Cl, R 2 =H, M= Ti; Cp'Ti(L)Cl2, where Cp' = cyclopentadienyl, R = 2, 4, 6-trimethylphenyl, R 1 = Cl, R 2 = H, M = Ti; Cp'Zr(L)Cl2, where Cp' = cyclopentadienyl, R = 2, 6-diisopropylphenyl, R 1 = Cl, R 2 = H, M = Zr; Cp'Ti(L)Me2, where Cp' = cyclopentadienyl, R = 2, 6-diisopropylphenyl, R 1 =Me,R 2 = H, M = Ti.

2. A method for preparing the single metallocene compound Cp'Ti(L)Cl2 or Cp'Zr(L)Cl2 according to claim 1, characterized in that: The following steps are involved: Under an argon atmosphere, a borane ligand 1,3-di(aryl or alkyl) five-membered ring diazaborane hydroxy compound and sodium hydride are dissolved in a good solvent and reacted at 20-40°C for a first time. A metal ligand Cp'MCl3 is added at -78-80°C, and a second reaction is continued in a good solvent at 20-40°C. After removing the good solvent, a poor solvent is added, the mixture is precipitated, filtered, and then the poor solvent is removed to obtain a monometallocene chloride, the general structural formula of which is shown in Formula (I): （I）； Wherein, the 1,3-bis(aryl or alkyl) five-membered ring diazaborol hydroxy compound is a 1,3-bis(2, 6-diisopropylphenyl) five-membered ring diazaborol hydroxy compound or a 1,3-bis(2, 4, 6-trimethylphenyl) five-membered ring diazaborol hydroxy compound.

3. A method for preparing the single metallocene compound Cp'Ti(L)Me2 according to claim 1, characterized in that: The following steps are involved: (1) Under an argon atmosphere, the borane ligand 1,3-di(aryl or alkyl) five-membered ring diazaboryl hydroxy compound and sodium hydride are dissolved in a good solvent and reacted at 20-40°C for the first time, the metal ligand Cp'MCl3 is added at -78-80°C, and the second reaction is continued in a good solvent at 20-40°C. After removing the good solvent, a poor solvent is added to settle and filter, and the poor solvent is removed again to obtain the intermediate product 1,3-di(aryl or alkyl) five-membered ring diazaboryloxy monometallocene chloride; (2) Under an argon atmosphere, 1,3-di(aryl or alkyl) five-membered ring diazaboryloxy monometallocene chloride is mixed with a Grignard reagent, and the mixture is reacted for a third time in an anhydrous solvent at 20-40° C., the anhydrous solvent is removed, a poor solvent is added, and the mixture is precipitated and filtered, and the poor solvent is removed to obtain the monometallocene compound, the general structural formula of which is shown in formula (I): （I）； Wherein, the 1,3-bis(aryl or alkyl) five-membered ring diazaborol hydroxy compound is a 1,3-bis(2, 6-diisopropylphenyl) five-membered ring diazaborol hydroxy compound.

4. The preparation method according to claim 2 or 3, characterized in that The distribution ratio of each component in step (1) is as follows: based on 1 mmol of the borane ligand 1,3-di(aryl or alkyl) five-membered ring diazaborane hydroxy compound, the amount of sodium hydride is 1-3 mmol, the amount of the good solvent is 10-30 mL, and the amount of the poor solvent is 10-30 mL.

5. The preparation method according to claim 2 or 3, characterized in that The distribution ratio of each component in step (1) is as follows: based on 1 mmol of the borane ligand 1,3-di(aryl or alkyl) five-membered ring diazaborane hydroxy compound, the amount of sodium hydride is 1.5-2 mmol, the amount of the good solvent is 15-25 mL, and the amount of the poor solvent is 15-25 mL.

6. The preparation method according to claim 2 or 3, characterized in that The molar ratio of the boron-oxygen ligand 1,3-di(aryl or alkyl) five-membered ring diazaborane hydroxy compound to the metal ligand Cp'MCl3 is 1:0.8-1.

5.

7. The preparation method according to claim 2 or 3, characterized in that The molar ratio of the boron-oxygen ligand 1,3-di(aryl or alkyl) five-membered ring diazaborane hydroxy compound to the metal ligand Cp'MCl3 is 1:1.0-1.

2.

8. The preparation method according to claim 2 or 3, characterized in that The time of the first reaction is 10 to 18 hours; the temperature of adding the metal ligand is 20 to 60° C.; and the condition of the secondary reaction is 10 to 18 hours.

9. The preparation method according to claim 2 or 3, characterized in that The time of the first reaction is 12 to 16 hours; the condition of the second reaction is 12 to 16 hours.

10. The preparation method according to claim 2 or 3, characterized in that: The good solvent is selected from one of diethyl ether and tetrahydrofuran; the poor solvent is selected from one of n-hexane, n-pentane, n-heptane and cyclohexane.

11. The preparation method according to claim 2 or 3, characterized in that: The good solvent is diethyl ether; the poor solvent is n-hexane.

12. The preparation method according to claim 3, characterized in that In step (2), the anhydrous solvent is selected from one of benzene, toluene, xylene, n-hexane, n-pentane, n-heptane, cyclohexane, and tetrahydrofuran.

13. The preparation method according to claim 3, characterized in that In step (2), the anhydrous solvent is toluene.

14. The preparation method according to claim 3, characterized in that In step (2), the molar ratio of the 1,3-di(aryl or alkyl) five-membered ring diazaboryloxy monometallocene chloride to the Grignard reagent is 0.8 to 1.2:3; based on 1 mmol of the borane ligand 1,3-di(aryl or alkyl) five-membered ring diazaboryl hydroxy compound, the amount of the good solvent is 10 to 30 mL; and the amount of the anhydrous solvent is 10 to 30 mL.

15. The preparation method according to claim 3, characterized in that In step (2), the molar ratio of the 1,3-di(aryl or alkyl) five-membered ring diazaboryloxy monometallocene chloride to the Grignard reagent is 1.0-1.2:3; based on 1 mmol of the borane ligand 1,3-di(aryl or alkyl) five-membered ring diazaboryl hydroxy compound, the amount of the good solvent is 15-25 mL; and the amount of the anhydrous solvent is 15-25 mL.

16. Use of the single metallocene compound according to claim 1, characterized in that: It is used to catalyze the copolymerization of ethylene with propylene, 1-octene, cyclobutene, cyclopentene, norbornene or 1,4,5,8-dimethyl-1,2,3,4,4a,5,8,8a-octahydronaphthalene (DMON).

17. The use of a single metallocene compound according to claim 16, characterized in that: The single metallocene compound is used to catalyze the copolymerization of ethylene and norbornene.

18. The use of a single metallocene compound according to claim 16, characterized in that: The single metallocene compound according to claim 1 is used as a catalyst precursor and methylaluminoxane MAO is used as a co-catalyst to catalyze the polymerization of ethylene and norbornene at 0-100 ° C. During the polymerization, the molar ratio of the catalyst precursor to methylaluminoxane MAO is 1:50-2000, and the molar ratio of the catalyst precursor to norbornene is 1:50-10000; the polymerization time is 1-60 minutes; and the polymerization solvent is selected from one of benzene, toluene, n-hexane, tetrahydrofuran and dichloromethane.

19. The use of a single metallocene compound according to claim 16, characterized in that: The single metallocene compound according to claim 1 is used as a catalyst precursor and methylaluminoxane MAO is used as a co-catalyst to catalyze the polymerization of ethylene and norbornene at 60 to 80 ° C. During the polymerization, the molar ratio of the catalyst precursor to methylaluminoxane MAO is 1:400 to 1200, and the molar ratio of the catalyst precursor to norbornene is 1:1500 to 5000; the polymerization time is 10 to 30 minutes; and the polymerization solvent is toluene.

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