Complex as well as preparation method and application thereof

Abstract

The invention relates to the field of metal complexes, in particular to a complex as well as a preparation method and application thereof. The complex has a structure as shown in a formula (a), and in the formula (a), M is one of IVB group metals; r1 is selected from at least one of aryl, aryl containing a first substituent, heterocyclic aryl and heterocyclic aryl containing a second substituent, and R2 is selected from at least one of alkyl, halogenated alkyl, cyano, ester group, alkenyl and alkynyl. The ligand part of the metal complex as shown in the formula (a) has an asymmetric structure and has better catalytic activity on polymerization reaction; # imgabs0 #

Description

Technical Field

[0001] The invention relates to the field of metal complexes, and in particular to a complex and a preparation method and application thereof. Background Art

[0002] Polyolefin refers to a series of substances that are formed by the polymerization of olefins with catalysts to form various functional polymers. Polyolefin has the characteristics of low relative density, good chemical resistance, water resistance, good mechanical strength, electrical insulation, etc. It can be used for films, pipes, plates, various molded products, wires and cables, etc. It has a wide range of uses in agriculture, packaging, electronics, electrical, automobiles, machinery, daily necessities, etc. The rapid development of metal catalysts has promoted the technological progress of olefin polymerization.

[0003] Non-transition metallocene catalysts refer to metal organic complexes in which the catalytically active metal center is a transition metal, such as metal atoms such as titanium, zirconium, and hafnium, and the ligands coordinated to the metal do not contain functional groups such as cyclopentadienyl and cyclopentadienyl derivatives. The coordinating atoms of such compounds are mainly nitrogen, oxygen, sulfur, phosphorus, etc. Such metal organic complexes can effectively catalyze olefin polymerization. Among them, mononuclear metal alkoxy or phenoxy non-titanium-based catalysts have good stability and high catalytic performance, and can be widely used in olefin polymerization reactions. Most of these catalysts are obtained by coordination of alcohol compounds of the same structure with titanium salts. If a catalyst for synthesizing an asymmetric ligand is used, multi-step reactions are generally inevitable, and non-titanium-based catalysts based on asymmetric pinacol groups are rarely reported. Summary of the invention

[0004] The purpose of the present invention is to overcome the problems of low reaction yield and complicated preparation method of complex ligand metal complexes in the prior art, and to provide a complex and its preparation method and application and olefin polymerization method. The complex has an asymmetric structure and better catalytic activity for polymerization reactions.

[0005] In order to achieve the above object, the present invention provides a complex having a structure as shown in formula (a).

[0006]

[0007] In formula (a), M is one of the Group IVB metals; R1 is selected from at least one of an aryl group, an aryl group containing a first substituent, a heterocyclic aryl group and a heterocyclic aryl group containing a second substituent; and R2 is selected from at least one of an alkyl group, a halogenated alkyl group, a cyano group, an ester group, an alkenyl group and an alkynyl group.

[0008] The second aspect of the present invention provides a method for preparing the complex, the method comprising: under an inert atmosphere,

[0009] (1) contacting a solvent, zinc powder, a first compound and a catalyst to perform a first heat treatment to obtain a first reaction solution;

[0010] (2) adding a second compound and a catalyst promoter to the first reaction liquid to perform a second heat treatment to obtain a second reaction liquid;

[0011] (3) adding a third compound to the second reaction liquid to perform a third heat treatment to obtain a third reaction liquid, removing the solvent, and purifying;

[0012] Wherein, the general formula of the first compound is shown in formula (c), and the general formula of the second compound is shown in formula (d):

[0013]

[0014] The third aspect of the present invention provides an application of the complex in olefin polymerization reaction.

[0015] Through the above technical solution, the present invention has the following advantages:

[0016] The ligand part of the metal complex represented by formula (a) of the present invention has an asymmetric structure, and M in the formula is one of the metals of Group IVB, R1 is selected from at least one of an aryl group, an aryl group containing a first substituent, a heterocyclic aryl group and a heterocyclic aryl group containing a second substituent, and R2 is selected from at least one of an alkyl group, a halogenated alkyl group, a cyano group, an ester group, an alkenyl group and an alkynyl group, and has better catalytic activity for polymerization reactions.

[0017] The metal complex of the present invention is prepared by the preparation method of the present invention (one-pot method), which has the advantages of simple preparation process, high reaction efficiency and fewer purification steps. DETAILED DESCRIPTION

[0018] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0019] The present invention provides a complex having a structure as shown in formula (a),

[0020]

[0021] In formula (a), M is one of the Group IVB metals; R1 is selected from at least one of an aryl group, an aryl group containing a first substituent, a heterocyclic aryl group and a heterocyclic aryl group containing a second substituent; and R2 is selected from at least one of an alkyl group, a halogenated alkyl group, a cyano group, an ester group, an alkenyl group and an alkynyl group.

[0022] The ligand part of the metal complex represented by formula (a) of the present invention has an asymmetric structure, and M in the formula is one of the metals of Group IVB, R1 is selected from at least one of an aryl group, an aryl group containing a first substituent, a heterocyclic aryl group and a heterocyclic aryl group containing a second substituent, and R2 is selected from at least one of an alkyl group, a halogenated alkyl group, a cyano group, an ester group, an alkenyl group and an alkynyl group, and has better catalytic activity for polymerization reactions.

[0023] According to a preferred embodiment of the present invention, in the formula (a), M is selected from one of Ti, Zr and Hf.

[0024] According to a preferred embodiment of the present invention, in the formula (a), M is Ti. By adopting the above-mentioned preferred embodiment, the catalytic performance of the complex can be further improved and the cost of raw materials can be reduced.

[0025] In the present invention, the aryl group can be a conventional choice in the art. According to a preferred embodiment of the present invention, the aryl group is selected from benzene and / or naphthalene, preferably benzene. By adopting the above-mentioned preferred embodiment, the catalytic performance of the complex can be further improved.

[0026] In the present invention, the heterocyclic aromatic group can be a conventional choice in the art. According to a preferred embodiment of the present invention, the heterocyclic aromatic group is selected from at least one of pyrrole, pyridine, furan, thiophene, carbazole, quinoline, isoquinoline, pyrimidine and indole. By adopting the above-mentioned preferred embodiment, the catalytic performance of the complex can be further improved.

[0027] According to a preferred embodiment of the present invention, R2 is selected from at least one of a C1-C10 alkyl group, a C1-C10 haloalkyl group, a cyano group, a C1-C5 carboxylate group, a C1-C10 alkenyl group and a C1-C10 alkynyl group.

[0028] According to a preferred embodiment of the present invention, R2 is selected from at least one of methyl, ethyl, n-propyl, isopropyl, tert-butyl, trifluoromethyl, chloroalkyl, bromoalkyl, cyano, acetate, vinyl, propenyl, ethynyl and propynyl, preferably trifluoromethyl. By adopting the above preferred embodiment, the catalytic performance of the complex can be further improved.

[0029] According to a preferred embodiment of the present invention, the first substituent and the second substituent are independently selected from at least one of halogen, alkyl, and alkoxy, preferably halogen and / or alkoxy, more preferably fluorine and / or methoxy. By adopting the above preferred embodiment, the catalytic performance of the complex can be further improved.

[0030] The present invention provides a method for preparing the complex, which comprises: in an inert atmosphere,

[0031] (1) contacting a solvent, zinc powder, a first compound and a catalyst to perform a first heat treatment to obtain a first reaction solution;

[0032] (2) adding a second compound and a catalyst promoter to the first reaction liquid to perform a second heat treatment to obtain a second reaction liquid;

[0033] (3) adding a third compound to the second reaction liquid to perform a third heat treatment to obtain a third reaction liquid, removing the solvent, and purifying;

[0034] Wherein, the general formula of the first compound is shown in formula (c), and the general formula of the second compound is shown in formula (d):

[0035]

[0036] The metal complex of the present invention is prepared by the preparation method of the present invention, which has the advantages of simple preparation process, high reaction efficiency and fewer purification steps.

[0037] In the present invention, the purification may be a conventional choice in the art. According to a preferred embodiment of the present invention, the purification is selected from at least one of recrystallization and pulping purification.

[0038] In the present invention, the catalyst may be a conventional choice in the art. According to a preferred embodiment of the present invention, the catalyst is an organic metal complex, preferably an organic Group IVB metal complex.

[0039] According to a preferred embodiment of the present invention, the catalyst is a complex represented by formula (b):

[0040]

[0041] In formula (b), M is one of the metals of Group IVB. By adopting the above-mentioned preferred embodiment, the efficiency of preparing the complex can be further improved.

[0042] According to a preferred embodiment of the present invention, the third compound is an organic metal complex, preferably an organic Group IVB metal complex, and more preferably a complex represented by formula (b).

[0043] According to a preferred embodiment of the present invention, in the formula (b), M is selected from one of Ti, Zr and Hf, preferably Ti.

[0044] In the present invention, the catalyst and the third compound may contain other selectable organic metal complexes such as TiCl4, tetrabutyl titanate, and tetraisopropyl titanate.

[0045] In the present invention, the catalyst co-agent may be a conventional choice in the art. According to a preferred embodiment of the present invention, the catalyst co-agent is an alkyl chlorosilane, preferably at least one of trimethyl chlorosilane and triethyl chlorosilane. By adopting the above preferred embodiment, the efficiency of complex preparation can be further improved.

[0046] In the present invention, the inert atmosphere may be a conventional choice in the art. According to a preferred embodiment of the present invention, the inert atmosphere is selected from at least one of a nitrogen atmosphere, a helium atmosphere and an argon atmosphere.

[0047] In the present invention, the solvent can be a conventional choice in the art. According to a preferred embodiment of the present invention, the solvent is selected from at least one of ethyl acetate, methyl acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane chloroform, dimethylformamide, and dimethyl sulfoxide.

[0048] In the present invention, there is no particular limitation on the amounts of the catalyst and zinc powder used in step (1). According to a preferred embodiment of the present invention, in step (1), the molar amount of the catalyst is 3-10%, preferably 5-10%, of the molar amount of the first compound; and the molar amount of the zinc powder is 100-200% of the molar amount of the first compound.

[0049] In the present invention, there is no particular limitation on the amounts of the second compound and the catalyst promoter in step (2). According to a preferred embodiment of the present invention, in step (2), the molar amount of the second compound is 100-200% of the molar amount of the first compound, preferably 150-200%; the molar amount of the catalyst promoter is 3-10% of the molar amount of the second compound, preferably 4-8%.

[0050] In the present invention, there is no particular limitation on the amount of the third compound used in step (3). According to a preferred embodiment of the present invention, in step (3), the molar amount of the third compound is 5-25% of the molar amount of the first compound, preferably 15-25%.

[0051] In the present invention, the conditions for the first heat treatment can be conventionally selected in the art. According to a preferred embodiment of the present invention, the conditions for the first heat treatment include: a temperature of 20-25°C, preferably 25°C; and / or a time of 1-5h, preferably 2-4h.

[0052] In the present invention, the conditions for the second heat treatment can be conventionally selected in the art. According to a preferred embodiment of the present invention, the conditions for the second heat treatment include: a temperature of 20-25°C, preferably 25°C; and / or a time of 1-12h, preferably 2-8h.

[0053] In the present invention, the conditions of the third heat treatment can be conventionally selected in the art. According to a preferred embodiment of the present invention, the conditions of the third heat treatment include: a temperature of 20-25°C, preferably 25°C; and / or a time of 6-24h, preferably 8-12h.

[0054] The invention provides an application of the complex in olefin polymerization reaction.

[0055] The complex of the present invention can have excellent catalytic activity when used in olefin polymerization.

[0056] The present invention will be described in detail below through examples. In the following examples, H NMR spectrum data were measured by liquid H NMR spectrum method; and the raw materials were all commercially available products.

[0057] Example 1

[0058] Benzophenone (546 mg, 3 mmol), zinc powder (192 mg, 3 mmol), b1 (56.4 mg, 0.3 mmol) and 10 mL of dichloromethane were added to a Schlenk bottle. After reacting at room temperature for 3 hours under a nitrogen atmosphere, hexafluoroacetone trihydrate (1.32 g, 6 mmol) and triethylsilyl chloride (22.6 mg, 0.15 mmol, 5%) were added. The reaction was continued at room temperature for 6 hours under a nitrogen atmosphere. Then b1 (423 mg, 0.75 mmol) was added and the reaction was continued at room temperature for 10 hours. The solvent was removed and the product was recrystallized in toluene to obtain 401 mg of product a1 with a yield of 72%. The molecular formula is C 32 H 20 F 12 O4Ti. 1 H NMR (400MHz,CDCl3):δ=7.46-7.40(m,8H),7.32-7.28(m,8H),7.22-7.17(m,4H). The reaction steps are as follows:

[0059]

[0060] Example 2

[0061] 4,4'-Dimethoxybenzophenone (726mg, 3mmol), zinc powder (192mg, 3mmol), b1 (56.4mg, 0.3mmol) and 10mL tetrahydrofuran were added to a Schlenk bottle. After reacting at room temperature for 3 hours under a nitrogen atmosphere, hexafluoroacetone trihydrate (1.32g, 6mmol) and trimethylsilyl chloride (16.3mg, 0.15mmol, 5%) were added. The reaction was carried out at room temperature for 6 hours under a nitrogen atmosphere, and b1 (423mg, 0.75mmol) was added. The reaction was carried out at room temperature for 10 hours. The solvent was removed and recrystallized in toluene to obtain 420mg of product a2 with a yield of 65%. The molecular formula is C 36 H 28 F 12 O8Ti. 1 H NMR (400MHz, CDCl3): δ = 7.35-7.31 (m, 8H), 7.12-7.08 (m, 8H), 3.85 (s, 12H).

[0062] Example 3

[0063] 4,4'-Dicyanobenzophenone (696mg, 3mmol), zinc powder (192mg, 3mmol), b1 (56.4mg, 0.3mmol) and 10mL dimethyl sulfoxide were added to a Schlenk bottle. After reacting at room temperature for 3 hours under a nitrogen atmosphere, hexafluoroacetone trihydrate (1.32g, 6mmol) and triethylsilyl chloride (22.6mg, 0.15mmol, 5%) were added. The reaction was carried out at room temperature for 6 hours under a nitrogen atmosphere, and b1 (423mg, 0.75mmol) was added. The reaction was carried out at room temperature for 10 hours. The solvent was removed and recrystallized in toluene to obtain a product a3440mg with a yield of 70%. The molecular formula is C 36 H 16 F 12 N4O8Ti. 1 H NMR (400MHz, CDCl3): δ = 7.84-7.80 (m, 8H), 7.52-7.49 (m, 8H).

[0064] Example 4

[0065] Benzophenone (546 mg, 3 mmol), zinc powder (192 mg, 3 mmol), b1 (56.4 mg, 0.3 mmol) and 10 mL of dichloromethane were added to a Schlenk bottle. After reacting at room temperature for 3 hours under a nitrogen atmosphere, acetone (348 mg, 6 mmol) and triethylsilyl chloride (22.6 mg, 0.15 mmol, 5%) were added. The reaction was continued at room temperature for 6 hours under a nitrogen atmosphere. Then b1 (423 mg, 0.75 mmol) was added and the reaction was continued at room temperature for 10 hours. The solvent was removed and the product was recrystallized in toluene to obtain 210 mg of product a4 with a yield of 53%. The molecular formula is C 32 H 32 O4Ti. 1 H NMR (400MHz, CDCl3): δ = 7.44-7.39 (m, 8H), 7.30-7.26 (m, 8H), 7.23-7.18 (m, 4H), 1.22 (s, 12H).

[0066] Example 5

[0067] Benzophenone (546 mg, 3 mmol), zinc powder (384 mg, 6 mmol), TiCl4 (1.42 g, 7.5 mmol) and 10 mL of dichloromethane were added to a Schlenk bottle. After reacting at room temperature for 3 hours under a nitrogen atmosphere, deionized water was added to quench the reaction, and the mixture was filtered. 30 mL of dichloromethane was added to the filtrate, and the mixture was washed three times with aqueous sodium bicarbonate solution. The organic phase was dried over anhydrous sodium sulfate, and the solvent was removed by spin drying. After separation by column, 274 mg of benzopinacol was obtained with a yield of 50%. Dissolve benzopinacol (274 mg, 0.75 mmol) in 10 mL of dichloromethane, add hexafluoroacetone trihydrate (0.5 g, 2.25 mmol), triethylchlorosilane (11.3 mg, 0.075 mmol, 10%) and tetrabutyl titanate (26 mg, 0.075 mmol), react at room temperature for 6 hours under nitrogen atmosphere, wash the reaction solution with sodium bicarbonate aqueous solution and deionized water respectively, combine and dry the organic phase with anhydrous sodium sulfate, remove the solvent, separate by silica gel column chromatography, and obtain a solid product (210 mg, yield 80%). Dissolve the solid product (210 mg, 0.6 mmol) obtained in the previous step in 10 mL of dichloromethane, add tetraisopropyl titanate (85.2 mg, 0.3 mmol), and react at room temperature for 10 hours. Remove the solvent, recrystallize, and obtain product a1 71.5 mg, yield 32%. The molecular formula is C 32 H 20 F 12 O4Ti. 1 H NMR (400MHz, CDCl3): δ = 7.46-7.40 (m, 8H), 7.32-7.28 (m, 8H), 7.22-7.17 (m, 4H).

[0068] It can be seen from the above examples that the present invention provides a new non-metallocene transition metal complex, which can be used to catalyze olefin polymerization reactions. In addition, the preferred embodiment of the present invention can realize a one-pot method for preparing the complex of the present invention, which significantly improves the preparation efficiency.

[0069] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A complex, characterized in that The complex has a structure as shown in formula (a), In formula (a), M is one of the Group IVB metals; R1 is selected from at least one of an aryl group, an aryl group containing a first substituent, a heterocyclic aryl group and a heterocyclic aryl group containing a second substituent; and R2 is selected from at least one of an alkyl group, a halogenated alkyl group, a cyano group, an ester group, an alkenyl group and an alkynyl group.

2. The complex according to claim 1, wherein In the formula (a), M is selected from one of Ti, Zr and Hf, preferably Ti; and / or The aryl group is selected from benzene and / or naphthalene, preferably benzene; and / or The heterocyclic aromatic group is selected from at least one of pyrrole, pyridine, furan, thiophene, carbazole, quinoline, isoquinoline, pyrimidine and indole; and / or The R2 is selected from at least one of C1-C10 alkyl, C1-C10 haloalkyl, cyano, C1-C5 carboxylate, C1-C10 alkenyl and C1-C10 alkynyl, preferably selected from at least one of methyl, ethyl, n-propyl, isopropyl, tert-butyl, trifluoromethyl, chloroalkyl, bromoalkyl, cyano, acetate, vinyl, propenyl, ethynyl and propynyl.

3. The complex according to claim 1 or 2, wherein The first substituent and the second substituent are each independently selected from at least one of halogen, alkyl, and alkoxy, preferably halogen and / or alkoxy, more preferably fluorine and / or methoxy.

4. The method for preparing the complex according to any one of claims 1 to 3, characterized in that: The method comprises: under an inert atmosphere, (1) contacting a solvent, zinc powder, a first compound and a catalyst to perform a first heat treatment to obtain a first reaction solution; (2) adding a second compound and a catalyst promoter to the first reaction liquid to perform a second heat treatment to obtain a second reaction liquid; (3) adding a third compound to the second reaction liquid to perform a third heat treatment to obtain a third reaction liquid, removing the solvent, and purifying; Wherein, the general formula of the first compound is shown in formula (c), and the general formula of the second compound is shown in formula (d):

5. The preparation method according to claim 4, wherein The catalyst is an organic metal complex, preferably an organic Group IVB metal complex, more preferably a complex represented by formula (b): and / or The third compound is an organic metal complex, preferably an organic Group IVB metal complex, more preferably a complex represented by formula (b): In formula (b), M is one of the Group IVB metals, preferably one selected from Ti, Zr and Hf, more preferably Ti.

6. The preparation method according to claim 4 or 5, wherein: The catalyst promoter is an alkyl chlorosilane, preferably at least one of trimethyl chlorosilane and triethyl chlorosilane; and / or The inert atmosphere is selected from at least one of a nitrogen atmosphere, a helium atmosphere and an argon atmosphere; and / or The solvent is selected from at least one of ethyl acetate, methyl acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane chloroform, dimethylformamide and dimethyl sulfoxide.

7. The preparation method according to any one of claims 4 to 6, wherein: In step (1), The molar amount of the catalyst is 3-10% of the molar amount of the first compound, preferably 5-10%; and / or The molar amount of zinc powder is 100-200% of the molar amount of the first compound.

8. The preparation method according to any one of claims 4 to 7, wherein: In step (2), The molar amount of the second compound is 100-200%, preferably 150-200%, of the molar amount of the first compound; and / or The molar amount of the catalyst promoter is 3-10% of the molar amount of the first compound, preferably 4-8%; and / or In step (3), The amount of the third compound used is 5-25% of the molar amount of the first compound, preferably 15-25%.

9. The preparation method according to any one of claims 4 to 7, wherein: The conditions of the first heat treatment include: a temperature of 20-25° C.; and / or a time of 1-5 h, preferably 2-4 h; and / or The conditions of the second heat treatment include: a temperature of 20-25°C; and / or a time of 1-12h, preferably 2-8h; and / or The conditions of the third heat treatment include: a temperature of 20-25° C.; and / or a time of 6-24 h, preferably 8-12 h.

10. Use of the complex according to any one of claims 1 to 3 in olefin polymerization.

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