Bisindolyl diphenoxy ether complex, preparation method thereof and olefin polymerization method

Abstract

The invention discloses a bis-indolyl bis-phenoxy ether complex, a preparation method thereof and an olefin polymerization method. The complex has extremely high catalytic activity, temperature resistance and cycloolefin insertion capability when being used for catalyzing copolymerization of ethylene and / or alpha-olefin and cycloolefin, and the prepared copolymerization product has extremely good optical properties such as good transparency, high refractive index and Abbe number; meanwhile, excellent mechanical properties such as high strength and good toughness are achieved. Therefore, the complex provided by the invention is very suitable for catalyzing the copolymerization reaction of ethylene and / or alpha-olefin and cycloolefin, and the obtained copolymerization product has a good industrial prospect in the processing application of the optical field.

Description

Technical Field

[0001] This invention relates to the field of olefin polymerization, specifically to a bisindolylbisphenoxy ether complex, its preparation method and uses, and also to an olefin polymerization method. Background Technology

[0002] Copolymerized carbon (COC) is a class of amorphous engineering plastics obtained by addition copolymerization of ethylene and / or α-olefins with cycloolefins under the action of coordination polymerization catalysts. Currently, the mainstream COCs on the market are the commercially available TOPAS and APEL series products launched by Polyplastics and Mitsui Chemicals of Japan.

[0003] Compared to traditional optical materials such as polymethyl methacrylate (PMMA) and polycarbonate (PC), carbon dioxide (COC) possesses comparable transmittance, refractive index, and birefringence, but the latter exhibits superior properties such as low hygroscopicity and low specific gravity. To achieve temperature resistance comparable to or even better than PMMA and PC, it is necessary to increase the insertion rate of cyclic olefins in COC. However, while improving temperature resistance, this increases the brittleness of COC, hindering processing. Therefore, the development of novel catalysts and catalytic systems is required.

[0004] COC catalysts mainly include Ziegler-Natta catalysts, metallocene and non-metallocene catalysts, etc. Ziegler-Natta catalysts are multi-site catalysts, capable of producing polymers with broad molecular weight distributions; however, they exhibit both addition copolymerization and ring-opening metathesis polymerization during COC polymerization, and their catalytic activity is low. Metallocene catalysts are single-site catalysts; while they possess excellent catalytic activity during polymerization, their products typically have a narrower molecular weight distribution, reducing the processability of the polymer resin. To address this issue, molecular weight distribution can be adjusted, such as by preparing bimodal polyolefins. For example, Chinese patents CN114736321A, CN114853947A, and CN105524217A respectively provide methods for preparing polymers with different molecular weight distributions. As mentioned above, the preparation of bimodal or multimodal polyolefins typically requires two or more catalysts and is achieved through specialized processes. Non-metallocene catalysts are a promising class of olefin polymerization catalysts, offering greater design and modification space for catalyst frameworks. The emergence of these catalysts may compensate for the shortcomings of existing catalytic systems in preparing polymer structures with diverse compositions, such as catalyzing the copolymerization of ethylene with α-olefins, dienes, cycloolefins, and even polar monomers. However, existing non-metallocene catalysts for COC polymerization suffer from low catalytic activity and low cycloolefin monomer insertion rates (i.e., COC glass transition temperature To). g Low), polymer structure, molecular weight (M w It faces numerous problems, including difficulties in regulating its distribution (PDI). Summary of the Invention

[0005] To develop more types of olefin coordination polymerization catalysts and improve their catalytic performance, one object of the present invention is to provide a bisindolylbisphenoxy ether complex that, as a main catalyst, can catalyze the polymerization of ethylene and / or α-olefins with cyclic olefins to obtain COCs with excellent optical properties that have both mechanical strength and toughness. Moreover, the complex of the present invention has extremely high catalytic activity, temperature resistance and cyclic olefin insertion ability.

[0006] Another object of the present invention is to provide a method for preparing the bisindolylbisphenoxy ether complex.

[0007] Another object of the present invention is to provide a method for olefin polymerization.

[0008] The first aspect of the present invention provides a bisindolylbisphenoxy ether complex with the structure shown in Formula I.

[0009]

[0010] Where M is selected from titanium, zirconium, or hafnium;

[0011] R1 to R9 are each independently selected from hydrogen, substituted or unsubstituted C1 to C40 hydrocarbon groups, C3 to C40 cyclic hydrocarbon groups, C6 to C40 aryl groups, heteroatom-containing groups, or silane groups containing 1 to 3 Si atoms; multiple R1 to R9 can bond with each other to form cyclic hydrocarbon groups.

[0012] X is selected from halogen, -NH2, substituted or unsubstituted C1-C20 alkyl, -NR'2, C6-C20 aryl or benzyl, wherein R' is selected from C1-C20 alkyl;

[0013] Y is selected from substituted or unsubstituted C1-C20 hydrocarbon groups, C3-C20 cyclic hydrocarbon groups, hydrocarbon groups containing heteroatoms (such as oxygen), or silane groups containing 1-3 Si atoms;

[0014] When the above-mentioned groups are substituted groups, the number of substituents is 1, 2, 3, 4 or 5, each independently selected from halogens, C1-C10 alkyl groups, C1-C10 alkoxy groups, C3-C10 cycloalkyl groups, C6-C20 aryl groups or benzyl groups.

[0015] Preferably, in the bisindolylbisphenoxy ether complex provided by the present invention, R1 to R9 are each independently selected from hydrogen, C1-C12 hydrocarbon group, C3-C16 cyclic hydrocarbon group, or C6-C18 aryl group. In some preferred embodiments, R1 to R9 are each independently selected from hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, or (substituted) phenyl, methoxy, etc., or multiple R1 to R9 can be bonded to each other to form a cyclic hydrocarbon group.

[0016] Preferably, in the bisindolylbisphenoxy ether complex provided by the present invention, X is selected from halogens, C1-C4 alkyl groups, benzyl groups, or -NR'2, wherein R' is selected from C1-C4 alkyl groups. In some preferred embodiments, X is selected from halogens, including F, Cl, Br, and I. In some more preferred embodiments, X is selected from Cl.

[0017] Preferably, when Y is a substituted group, the number of substituents is 1, 2, 3, 4, or 5, each independently selected from C1-C10 hydrocarbon groups, C1-C10 alkoxy groups, C3-C10 cyclic hydrocarbon groups, and silane groups containing 1 to 3 Si atoms. In some preferred embodiments, Y is selected from C1-C6 alkyl groups, C3-C8 cyclic alkyl groups, or C1-C6 alkoxy ether groups, etc.

[0018] The bisindolylbisphenoxy ether complexes provided by this invention are further preferably selected from any one of the following complexes Cat.1 to Cat.6:

[0019] Cat.1 Cat.2

[0020] Cat.3 Cat.4

[0021] Cat.5 Cat.6

[0022] A second aspect of the present invention provides a method for preparing the aforementioned bisindolylbisphenoxy ether complex, comprising the following steps:

[0023] S1: Synthesize phenoxy ether compound IV from compounds II and III via the Williamson reaction;

[0024] S2: Compound IV is dissolved in a solvent, then alkyl lithium is added at low temperature for lithiation, followed by the addition of trimethyl borate for reaction, and then hydrolysis with hydrochloric acid aqueous solution to obtain compound V;

[0025] S3: Compound V is coupled with a brominated derivative of indole or its derivative (VI) under alkaline conditions via a Suzuki coupling reaction catalyzed by a palladium catalyst to obtain the ligand compound;

[0026] S4: The ligand compound is reacted with alkyllithium to obtain a lithium salt of the ligand compound, which is then reacted with MX4 (or its ether complex); or, the ligand compound is directly reacted with MR2X2 (or its ether complex) to obtain the bisindolylbisphenoxy ether complex.

[0027]

[0028] As a preferred embodiment, in step S1 of the present invention, compounds II and III are added to acetone at room temperature, followed by an alkali-catalyzed reaction and reflux to obtain compound IV.

[0029] In Formulas II and IV of this invention, X1 is selected from halogens, preferably Br.

[0030] As a preferred embodiment, in step S1 of the present invention, the alkali is one or more of NaOH, KOH, Ba(OH)2, Ca(OH)2, K2CO3, K3PO4, Na2CO3, Cs2CO3, etc.

[0031] As a preferred embodiment, in step S1 of the present invention, the molar ratio of compound II to compound III is 1:(0.5-10), preferably 1:(0.5-1).

[0032] As a preferred embodiment, in step S1 of the present invention, the molar ratio of compound II to the base is 1:(1-10), preferably 1:(1-2).

[0033] As a preferred embodiment, in step S1 of the present invention, the amount of acetone used is 0.1 to 100 mL of acetone per millimole of compound II, preferably 1 to 10 mL of acetone per millimole of compound II.

[0034] As a preferred embodiment, in step S1 of the present invention, the reaction temperature is 30–100°C, preferably 50–70°C.

[0035] As a preferred embodiment, in step S1 of the present invention, the reaction time is 0.1 to 100 h, preferably 1 to 10 h.

[0036] As a preferred embodiment, in step S1 of this invention, the reaction is carried out in an N2 or air atmosphere; after the reaction is completed, post-processing processes such as separation and purification are also included, which are conventional operations in the field and are not particularly required by this invention. For example, in some specific embodiments, the methods that can be adopted include: removing the solvent by rotary evaporation or reduced pressure, extracting and separating the liquid with water, dichloromethane (DCM) or ethyl acetate, drying with anhydrous Na2SO4 or MgSO4, and then purifying by column chromatography, recrystallization or slurrying with organic solvents to obtain the target product.

[0037] As a preferred embodiment, in step S2 of the present invention, the solvent is one or more of benzene, toluene, xylene, chlorobenzene, n-hexane, n-heptane, dichloromethane, 1,2-dichloroethane, tetrachloroethane, tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, n-propyl ether, isopropyl ether, methyl tert-butyl ether, ethylene glycol dimethyl ether, and dioxane, preferably one or more of tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, and methyl tert-butyl ether.

[0038] As a preferred embodiment, in step S2 of the present invention, the alkyl lithium is one or more of C1 to C6 alkyl lithium, preferably one or more of methyl lithium, n-butyl lithium, and n-hexyl lithium.

[0039] As a preferred embodiment, in step S2 of the present invention, the concentration of the hydrochloric acid aqueous solution is 0.1 to 10N, preferably 1 to 2N.

[0040] As a preferred embodiment, in step S2 of the present invention, the molar ratio of compound IV, alkyllithium, trimethyl borate and hydrochloric acid is 1:(1-3):(1-10):(1-50), preferably 1:(2-2.2):(2-4):(4-20).

[0041] As a preferred embodiment, in step S2 of the present invention, the amount of solvent used is 0.1 to 100 mL of solvent per millimole of compound IV, preferably 1 to 10 mL of solvent per millimole of compound IV.

[0042] As a preferred embodiment, in step S2 of the present invention, when adding alkyllithium and trimethyl borate, the reaction system temperature is -80 to 40°C, preferably -80 to 0°C. After adding alkyllithium, the reaction system temperature is -80 to 40°C, preferably -80 to -40°C, and the reaction time is 0.1 to 100 h, preferably 0.1 to 10 h. After adding trimethyl borate, the reaction system temperature is -80 to 40°C, preferably 0 to 25°C, and the reaction time is 0.1 to 100 h, preferably 1 to 10 h.

[0043] As a preferred embodiment, in step S2 of the present invention, the reaction system temperature is -80 to 40°C, preferably -10 to 10°C, when the hydrochloric acid aqueous solution is added. After adding the hydrochloric acid aqueous solution, the reaction system temperature is -80 to 40°C, preferably 0 to 25°C, and the reaction time is 0.1 to 100 h, preferably 1 to 10 h.

[0044] As a preferred embodiment, in step S2 of this invention, the reaction is carried out in an N2 or Ar atmosphere; after the reaction is completed, post-processing processes such as separation and purification are also included, which are conventional operations in the field and are not particularly required by this invention. For example, in some specific embodiments, the methods that can be adopted include: removing the solvent by rotary evaporation or reduced pressure, extracting and separating the liquid with water, dichloromethane (DCM) or ethyl acetate, drying with anhydrous Na2SO4 or MgSO4, and then purifying by column chromatography, recrystallization or slurrying with organic solvents to obtain the target product.

[0045] In formula (V) of this invention, Z is a boric acid group, selected from -B(OH)2.

[0046] As a preferred embodiment, in step S3 of the present invention, the alkali is one or more of NaOH, KOH, Ba(OH)2, Ca(OH)2, K2CO3, K3PO4, Na2CO3, Cs2CO3, TlOH, KF, CsF, Bu4NF, NaOCH2CH3, N(CH2CH3)3, etc., preferably one or more of NaOH, KOH, K2CO3, Na2CO3, and Cs2CO3.

[0047] As a preferred embodiment, in step S3 of the present invention, the palladium catalyst is Pd(PPh3)4, Pd(dppf)Cl2, Pd(OAc)2, PdCl2, PdCl2(PPh3)2, Pd(OAc)2(PPh3)2, Pd(OAc)2(P(Cy)3)2, Pd(P t One or more of the following: Bu3)2, PdCl2(P(Cy)3)2, PdCl(Bn)(PPh3)2, and Pd2(dba)3, preferably Pd(PPh3)4, Pd(dppf)Cl2, and Pd(P t One or more of Bu3)2 and Pd2(dba)3.

[0048] As a preferred embodiment, step S3 of the present invention is carried out in the presence of a solvent, wherein the solvent is one or more selected from benzene, toluene, xylene, chlorobenzene, n-hexane, n-heptane, dichloromethane, 1,2-dichloroethane, tetrachloroethane, tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, n-propyl ether, isopropyl ether, methyl tert-butyl ether, ethylene glycol dimethyl ether, dioxane, water, methanol, ethanol, and isopropanol, preferably one or more selected from toluene, xylene, dioxane, water, and ethanol.

[0049] As a preferred embodiment, in step S3 of the present invention, the amount of solvent used is 0.1 to 1000 mL of solvent per millimole of compound V, preferably 1 to 100 mL of solvent per millimole of compound V.

[0050] As a preferred embodiment, in step S3 of the present invention, the molar ratio of compound V, compound VI, base, and palladium catalyst is 1:(0.1~100):(0.1~100):(0.0001~1), preferably 1:(0.1~10):(0.1~10):(0.001~0.1).

[0051] As a preferred embodiment, in step S3 of the present invention, the reaction temperature is 0–160°C, preferably 40–130°C.

[0052] As a preferred embodiment, in step S3 of the present invention, the reaction time is 0.1 to 100 h, preferably 1 to 10 h.

[0053] As a preferred embodiment, in step S3 of this invention, the reaction is carried out in an N2 or Ar atmosphere; after the reaction is completed, post-processing processes such as separation and purification are also included, which are conventional operations in the field and are not particularly required by this invention. For example, in some specific embodiments, the methods that can be adopted include: removing the solvent by rotary evaporation or reduced pressure, extracting and separating the liquid with water, dichloromethane (DCM) or ethyl acetate, drying with anhydrous Na2SO4 or MgSO4, and then purifying by column chromatography, recrystallization or slurrying with organic solvents to obtain the target product.

[0054] As a preferred embodiment, in step S4 of the present invention, the alkyl lithium is one or more of C1 to C6 alkyl lithium, preferably one or more of methyl lithium, n-butyl lithium, and n-hexyl lithium.

[0055] As a preferred embodiment, in step S4 of the present invention, the ether is one or more of tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, n-propyl ether, isopropyl ether, methyl tert-butyl ether, ethylene glycol dimethyl ether, and dioxane, preferably one or more of tetrahydrofuran, diethyl ether, and n-propyl ether.

[0056] As a preferred embodiment, step S4 of the present invention is carried out in the presence of a solvent, wherein the solvent is one or more selected from benzene, toluene, xylene, chlorobenzene, n-hexane, n-heptane, dichloromethane, 1,2-dichloroethane, tetrachloroethane, tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, n-propyl ether, isopropyl ether, methyl tert-butyl ether, ethylene glycol dimethyl ether, and dioxane, preferably one or more selected from toluene, n-hexane, n-heptane, tetrahydrofuran, and diethyl ether.

[0057] As a preferred embodiment, in step S4 of the present invention, the amount of solvent used is 0.1 to 1000 mL of solvent per millimole of ligand, preferably 1 to 100 mL of solvent per millimole of ligand.

[0058] In step S4 of this invention, MX4 is selected from one or more of TiCl4, ZrCl4, and HfCl4.

[0059] In step S4 of this invention, R in MR2X2 is selected from C1-C20 alkyl, aryl, or benzyl groups. Examples include ZrBn2Cl2 and HfBn2Cl2.

[0060] As a preferred embodiment, in step S4 of the present invention, the molar ratio of the ligand, alkyllithium, MX4 (or its ether complex) is 1:(0.1-100):(0.1-100), preferably 1:(1-3):(1-3).

[0061] As a preferred embodiment, in step S4 of the present invention, the molar ratio of the ligand to MR2X2 (or its ether complex) is 1:(0.1-100), preferably 1:(1-3).

[0062] As a preferred embodiment, in step S4 of the present invention, the reaction temperature of the ligand, alkyllithium, and MX4 (or its ether complex) is -80 to 50°C, preferably -10 to 25°C. The reaction time of the ligand with alkyllithium is 0.1 to 100 h, preferably 0.1 to 10 h. The reaction time of the lithium salt of the ligand with MX4 (or its ether complex) is 0.1 to 100 h, preferably 1 to 30 h.

[0063] As a preferred embodiment, in step S4 of the present invention, the reaction temperature of the ligand and MR2X2 (or its ether complex) is -20 to 150°C, preferably 25 to 110°C. The reaction time of the ligand and MR2X2 (or its ether complex) is 0.1 to 100 h, preferably 1 to 30 h.

[0064] As a preferred embodiment, in step S4 of the present invention, the reaction is carried out in an N2 or Ar atmosphere; after the reaction is completed, post-processing processes such as separation and purification are also included, which are conventional operations in the field and are not particularly required by the present invention. For example, in some specific embodiments, the methods that can be adopted include: filtering to separate the filtrate and solid residue, removing the solvent under reduced pressure, and purifying the target product by recrystallization or pulping with organic solvent.

[0065] A third aspect of the invention provides the use of the aforementioned bisindolylbisphenoxy ether complex as a master catalyst for olefin polymerization.

[0066] The complex structure provided by this invention, due to the unique coordination space and electronic effects of the active center, exhibits extremely high catalytic activity and excellent high-temperature resistance when catalyzing the polymerization of ethylene and / or α-olefins with cycloolefins. It can withstand higher polymerization temperatures, thus possessing better thermal stability and extending service life. Furthermore, it reduces the distribution of di-, tri-, and higher segments in cycloolefins, with ethylene and cycloolefins primarily consisting of alternating segments. This results in a more uniform distribution of cycloolefins in the copolymer (COC), better stereoregularity, and improved COC transparency while maintaining high refractive index and high Abbe number. The low content of terminal double bonds in the copolymer also avoids problems such as high-temperature yellowing, making it more suitable for applications in the optical field. In addition, when the complex provided by this invention catalyzes the copolymerization of ethylene and / or α-olefins with cycloolefins, the resulting polymer maintains its high mechanical strength while exhibiting excellent toughness and ease of processing. This is presumably due to the high degree of branching or long-chain branched structure of the COC in this invention. Therefore, the complex provided by this invention is highly suitable for catalyzing the polymerization of olefins, especially the copolymerization of ethylene and / or α-olefins with cycloolefins.

[0067] In the applications provided by this invention, the olefin polymerization is a copolymerization of ethylene and / or α-olefins with cyclic olefins. In some preferred embodiments, the α-olefin is a C3-C12 α-olefin, including but not limited to one or more of 1-propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene; and the cyclic olefin is a C6-C21 cyclic olefin, including but not limited to one or more of cyclohexene, norbornene, and tetracyclododecene.

[0068] A fourth aspect of the present invention provides an olefin polymerization method, wherein ethylene and / or α-olefins are polymerized with cycloolefins in the presence of a main catalyst and a co-catalyst to form an olefin copolymer; wherein the main catalyst is the bisindolylbisphenoxy ether complex.

[0069] In some preferred embodiments of the polymerization method provided by the present invention, the α-olefin is a C3 to C12 α-olefin, including but not limited to one or more of 1-propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene, and the cyclic olefin is a C6 to C21 cyclic olefin, including but not limited to one or more of cyclohexene, norbornene, and tetracyclododecene.

[0070] In the polymerization method provided by this invention, the molar ratio of the main catalyst to the co-catalyst is 1:1 to 5000. In some preferred embodiments, the molar ratio of the main catalyst to the co-catalyst is 1:1 to 2000, including but not limited to molar ratios of about 1:1, about 1:2, about 1:4, about 1:6, about 1:8, about 1:10, about 1:20, about 1:40, about 1:60, about 1:80, about 1:100, about 1:200, about 1:400, about 1:600, about 1:800, about 1:1000, about 1:1200, about 1:1500, about 1:1800, about 1:2000, or any combination thereof. In some more preferred embodiments, the molar ratio of the main catalyst to the co-catalyst is 1:1 to 1500.

[0071] In the polymerization method provided by this invention, the co-catalyst can be any type commonly found in the art. In some preferred embodiments, the co-catalyst is selected from one or more of alkylaluminum, alkylaluminum chloride, aluminoxane, and boron-containing additives. In some more preferred embodiments, the alkylaluminum is selected from one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, and tri-n-octylaluminum; the alkylaluminum chloride is selected from one or more of diethylaluminum chloride, diethylaluminum chloride, and sesqui-diethylaluminum chloride; the aluminoxane is selected from one or more of methylaluminoxane, ethylaluminoxane, and isobutylaluminoxane; and the boron-containing additive is selected from one or both of tris(pentafluorophenyl)borane and triphenylcarbazone(pentafluorophenyl)borate.

[0072] In the polymerization method provided by this invention, as a preferred embodiment, the co-catalyst is selected from methylaluminoxane (MAO); or the co-catalyst is selected from a combination of methylaluminoxane and triisobutylaluminum in a molar ratio of 1 to 50:1, including but not limited to molar ratios of about 1:1, about 2:1, about 5:1, about 10:1, about 15:1, about 20:1, about 25:1, about 30:1, about 35:1, about 40:1, about 45:1, about 50:1, or any combination thereof. In some preferred embodiments, the co-catalyst is selected from a combination of methylaluminoxane and triisobutylaluminum in a molar ratio of 2 to 30:1.

[0073] In the polymerization method provided by this invention, as a preferred embodiment, the co-catalyst is selected from a combination of a boron-containing auxiliary agent and an alkyl aluminum; the co-catalyst is selected from a combination of a boron-containing auxiliary agent and an alkyl aluminum in a molar ratio of 1:1 to 3000, including but not limited to molar ratios of about 1:10, about 1:20, about 1:50, about 1:100, about 1:150, about 1:200, about 1:250, about 1:300, about 1:350, about 1:400, about 1:450, about 1:500, or any combination thereof. In some preferred embodiments, the co-catalyst is selected from a combination of triphenylcarbatetra(pentafluorophenyl)borate and triisobutylaluminum in a molar ratio of 1:300.

[0074] In the polymerization method provided by this invention, as a preferred embodiment, the co-catalyst is selected from a combination of a boron-containing auxiliary agent and MAO (or modified methylaluminoxane, MMAO); the co-catalyst is selected from a combination of a boron-containing auxiliary agent and MAO (or MMAO) in a molar ratio of 1:1 to 3000, including but not limited to molar ratios of about 1:10, about 1:20, about 1:50, about 1:100, about 1:150, about 1:200, about 1:250, about 1:300, about 1:350, about 1:400, about 1:450, about 1:500, or any combination thereof. In some preferred embodiments, the co-catalyst is selected from a combination of triphenylcarbatetra(pentafluorophenyl)borate and MAO in a molar ratio of 1:500.

[0075] In the polymerization method provided by this invention, the characteristics of the prepared polymer products, especially the cyclic olefin monomer insertion rate and polymer microstructure of copolymers (e.g., copolymers of ethylene and norbornene), can be adjusted within a wide range by regulating the structure of the main catalyst and the polymerization process conditions. Moreover, even if the polymerization is carried out at a high temperature (130°C), the polymerization activity of the catalyst is not significantly sacrificed and can still be maintained at a high level (as shown in Table 1).

[0076] In the polymerization method provided by this invention, the reaction temperature of the polymerization reaction is 50–200°C. Within this range, it can be appropriately adjusted by those skilled in the art according to the actual reaction conditions such as the polymerization type and the type of monomer. In some preferred embodiments, the reaction temperature of the polymerization reaction is 90–180°C. In some more preferred embodiments, the reaction temperature of the polymerization reaction is higher than 110°C, for example, 110–140°C.

[0077] The bisindolylbisphenoxy ether complex provided by this invention has good high-temperature stability and can maintain high polymerization activity at high reaction temperatures (e.g., 150°C), while commonly used catalysts in the art (including metallocenes with single or dual active centers, or non-metallocene catalysts with single or dual active centers) can only withstand polymerization temperatures of no more than 130°C.

[0078] In the polymerization method provided by this invention, the reaction pressure of the polymerization reaction is 0.01–10 MPa. Within this range, it can be appropriately adjusted by those skilled in the art according to the actual reaction conditions such as the polymerization type and the type of monomer. In some preferred embodiments, the reaction pressure of the polymerization reaction is 0.1–3 MPa.

[0079] In the polymerization method provided by this invention, the reaction time of the polymerization reaction is 0.1 to 1000 min. Within this range, it can be appropriately adjusted by those skilled in the art according to the actual reaction conditions such as the polymerization type and the type of monomer. In some preferred embodiments, the reaction time of the polymerization reaction is 1 to 100 min, for example, 1 to 30 min.

[0080] The polymerization method provided by this invention can be a solution polymerization process, that is, the polymerization reaction is carried out in a solvent, and the solvent used can be any type commonly used in the art.

[0081] In the polymerization method provided by the present invention, other process steps and post-processing steps besides the above-mentioned process parameters can all adopt conventional techniques in the field, or can be appropriately adjusted by those skilled in the art according to the actual reaction conditions such as polymerization type and type of polymerizing monomer.

[0082] To overcome the shortcomings of existing olefin coordination polymerization catalysts, this invention optimizes the steric and electronic effects of the catalytic active center by rationally designing the catalyst framework structure and modifying groups. This results in a catalyst with high catalytic activity, high cyclic olefin monomer insertion rate, and a well-structured polymer microstructure. w PDI is an excellent catalyst that is easily tunable and has high-temperature resistance. The COC obtained using the bisindolylbisphenoxy ether complex described in this invention as the main catalyst exhibits good optical properties (high transparency, resistance to yellowing, refractive index and Abbe number comparable to PC and PMMA), as well as high strength, good toughness, and ease of processing. This allows for the production of a wider variety of novel COC products to meet increasingly diverse application needs.

[0083] The technical solution provided by this invention has the following advantages:

[0084] (1) The complex provided by the present invention has extremely high catalytic activity and good high temperature resistance, and is very suitable for catalyzing the polymerization reaction of olefins, especially the copolymerization reaction of ethylene and / or α-olefins with cycloolefins.

[0085] (2) Compared with existing metallocene and non-metallocene complex catalysts, the complex provided by this invention, as the main catalyst, reduces the distribution of di-, tri-, and higher cyclic olefin segments in the COC obtained by the copolymerization reaction of ethylene and / or α-olefins with cyclic olefins. Ethylene and cyclic olefins are mainly composed of alternating isotactic segments, which makes the distribution of cyclic olefins in COC more uniform and the stereoregularity better. While maintaining high refractive index and low birefringence, it improves the transparency of COC. Moreover, the copolymer has a low content of terminal double bonds, avoiding problems such as yellowing during processing, and is more suitable for applications in the optical field.

[0086] (3) When the complex provided by the present invention catalyzes the copolymerization of ethylene and / or α-olefins with cycloolefins, COCs with different mechanical properties can be obtained by controlling the structure of the complex, thereby increasing their toughness and making them easier to process while maintaining their high mechanical strength.

[0087] (4) The method for preparing the complex provided by the present invention is simple, and the reaction raw materials and intermediates are easy to synthesize. It does not require complicated process steps and high costs, and can be adapted to large-scale production and use.

[0088] (5) The olefin polymerization method provided by the present invention has high polymerization activity, simple process, strong operability, and can adapt to a variety of olefin monomers, especially cyclic olefin monomers with large steric hindrance, and has very important industrial and economic value. Detailed Implementation

[0089] As used herein, "C1-Cn" includes C1-C2, C1-C3, ..., C1-Cn. For example, the "C1-C10" group refers to a portion having 1 to 10 carbon atoms, i.e., the group contains 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. Therefore, for example, "C1-C4 alkyl" refers to an alkyl group containing 1 to 4 carbon atoms, i.e., the alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl. Numerical ranges in this document, such as "1-6," refer to integers within a given range.

[0090] The term "alkyl" as used alone or in combination herein refers to a saturated aliphatic hydrocarbon that is optionally substituted with a straight chain or optionally substituted with a branched chain. "alkyl" as used herein preferably has 1 to 10 carbon atoms, for example, 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or 1 to 5 carbon atoms, or 1 to 4 carbon atoms, or 1 to 3 carbon atoms. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, 2-methyl-1-propyl, 2-methyl-2-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-3-butyl, 2,2-dimethyl-1-propyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2,2-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, and hexyl, as well as longer alkyl groups such as heptyl and octyl. When the group defined in this article, such as "alkyl", has a numerical range, for example, "C1 to C6 alkyl" means an alkyl group that can be composed of 1, 2, 3, 4, 5 or 6 carbon atoms. The alkyl group in this article also includes cases where no numerical range is specified.

[0091] The term “alkyl” as used in this article refers to an alkyl group linked to other groups, such as an alkyl group in an alkoxy group, and is defined the same as when used alone.

[0092] The term "alkoxy" as used alone or in combination herein refers to an alkyl ether group, denoted as "alkyl-O-". Non-limiting examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, etc.

[0093] The term "cycloalkyl" as used alone or in combination herein refers to a non-aromatic saturated carbon ring, which may include a single-carbon ring (having one ring), a double-carbon ring (having two rings), or a multi-carbon ring (having more than two rings), and the rings may be bridged or spirocyclic. Preferably, the cycloalkyl group has 3 to 10 cyclic carbon atoms, for example, 3 to 8 cyclic carbon atoms, or 3 to 6 cyclic carbon atoms. Non-limiting examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc.

[0094] The term "aryl" as used alone or in combination herein refers to an optionally substituted aromatic hydrocarbon group, preferably having 6 to 20, such as 6 to 12 or 6 to 10 cyclic carbon atoms, which can be monocyclic, bicyclic, or more cyclic aryl groups. A bicyclic or more cyclic aryl group can be a monocyclic aryl group fused with other independent rings, such as alicyclic or aromatic rings. Non-limiting examples of monocyclic aryl groups include phenyl; non-limiting examples of bicyclic aryl groups include naphthyl; non-limiting examples of polycyclic aryl groups include phenanthryl, anthracene, fluorenyl, and azulel.

[0095] The term “halogen” as used alone or in combination in this article refers to fluorine, chlorine, bromine or iodine.

[0096] The term "α-olefin" as used alone or in combination herein refers to a monoolefin with a double bond at the end of the molecular chain, and its molecular formula may be represented as R-CH=CH2, where R represents "C1-C10 alkyl". The olefin has, but is not limited to, 3 to 12 carbon atoms, for example, 3 to 12 carbon atoms, 3 to 10 carbon atoms, or 3 to 8 carbon atoms. The double bond in these groups may be in cis or trans conformation and should be understood to include both isomers. The olefin as defined herein may be a single type of olefin or a mixture of multiple olefins.

[0097] The terms "R1~R" used individually or in combination in this article n "Refers to groups R1, R2, R3, ... R n That is, it refers to all R groups in the range of subscripts 1 to n.

[0098] The term "hydrocarbon group" as used alone or in combination in this article includes alkanes, alkenes, aromatics and alkynes, and can be a straight-chain or branched group or a cyclic group.

[0099] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0100] Unless otherwise specified, all reagents or raw materials used in the embodiments of this invention are commercially available products.

[0101] Unless otherwise specified, all percentages used in the embodiments of this invention are mass percentages.

[0102] The testing methods used in the embodiments of the present invention are as follows:

[0103] Polymer molecular weight (M) w ) and molecular weight distribution (PDI, M w / M nThe determination was performed by high-temperature gel permeation chromatography (PL-GPC220) with 1,2,4-trichlorobenzene as the mobile phase and polystyrene as the standard at 150℃. The standard concentration was 0.1 mg / mL, the solvent flow rate was 1.0 mL / min, and the standard parameters were K = 59.1, α = 0.69. The sample parameters were K = 14.1, α = 0.70.

[0104] Melting point of polymer (T) m ) and glass transition temperature (T g The determination was performed using a differential scanning calorimeter (METTLER, DSC-1). The procedure was as follows: 5.0-7.0 mg of polymer sample was taken, heated to 250 °C at a rate of 30 °C / min and held for 5 min to eliminate thermal history, then cooled to 0 °C at a rate of 10 °C / min and held for 3 min, and then heated to 250 °C again. The crystallization peak temperature was obtained using the cooling curve, and the melting point or glass transition temperature of the polymer was calculated from the curve of the second heating process.

[0105] The cyclic olefin monomer insertion rate and [ENEN] configuration (alternating ethylene and norbornene) content in ethylene and / or α-olefin-cyclic olefin copolymers are determined by... 13 ¹³C NMR (Bruker ADVANCE Ⅲ 400M) determination. The polymer was dissolved in deuterated 1,2-o-dichlorobenzene at 130 °C, with a concentration of approximately 100 mg / mL. Instrument parameters: pulse angle 30 degrees, full decoupling, pulse delay time 3 s, sample scans exceeding 3000. The obtained high-temperature... 13 After assigning the peaks in the C NMR spectrum, the sequence distribution of the copolymer and the comonomer insertion rate were obtained.

[0106] Tensile tests were conducted using an electronic universal testing machine from Instron, USA, to test the tensile mechanical properties of the polymer and obtain the polymer stress-strain curves and related mechanical parameters.

[0107] The transmittance of the samples was measured using a UV-3600Plus UV-Vis spectrophotometer. The wavelength range of the test was 250–800 nm, and all test samples were 2 mm.

[0108] The terminal double bonds of the polymer were determined by iodometric titration.

[0109] The refractive index and Abbe number of the polymer were measured using an Abbe refractometer (DR-M4, ATAGO) at room temperature (25°C).

[0110] Example 1: Preparation of Cat.1 Complex

[0111]

[0112] The crafting route for Cat.1 is as follows:

[0113]

[0114]

[0115] (1) Preparation of intermediate IV-1: 50 mmol of 2-bromo-4-tert-butylphenol and 25 mmol of 1,2-dibromoethane were added to a 500 mL round-bottom flask, followed by 150 mL of acetone. After the reactants dissolved, 75 mmol of potassium hydroxide was added, and the mixture was refluxed at 60 °C for 5 h. Thin-layer chromatography (TLC) showed that the reaction was basically complete. After removing the acetone solvent by rotary evaporation, 100 mL of DCM and 100 mL of water were added to the residue, and the organic phase was collected by extraction. The aqueous phase was extracted with DCM (50 mL × 3). After mixing all the organic phases, the mixture was dried with anhydrous Na2SO4, filtered, and the solvent was removed by rotary evaporation. The residual solid was recrystallized in acetone to obtain a white solid, which was intermediate IV-1, with a yield of 90%.

[0116] 1 H NMR (500 MHz, Chloroform-d) δ7.30 (d, J = 1.5 Hz, 2H), 7.25 (dd, J = 7.5, 1.6 Hz, 2H), 6.91 (d, J = 7.5 Hz, 2H), 4.40 (t, J = 8.2 Hz, 4H), 1.33 (s, 18H).

[0117] (2) Preparation of intermediate V-1: Under a N2 atmosphere, 20 mmol of intermediate IV-1 and 100 mL of ultra-dry THF were added to a 500 mL Schlenk flask. 40 mmol of n-BuLi (1.6 M hexane solution) was added dropwise at -78 °C and the reaction was carried out for 30 min. Then, 40 mmol of B(OMe)3 was added, and the temperature was slowly raised to 25 °C and the reaction was carried out for 12 h. After the reaction was completed, 80 mL of 2N HCl was added at 0 °C, and the mixture was stirred at 25 °C for 1 h. 100 mL of water was added, and the mixture was allowed to stand and separate into layers. The organic phase was collected, and the aqueous phase was extracted with EtOAc (50 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4. After filtration, the solvent was removed by rotary evaporation of the filtrate to obtain a white solid product. The white solid product was further purified by washing with n-hexane (100 mL × 3) to obtain a white solid powder, which was intermediate V-1, with a yield of 82%.

[0118] 1H NMR (500 MHz, Chloroform-d) δ7.35 (d, J = 1.7 Hz, 2H), 7.28 (dd, J = 7.5, 1.5 Hz, 2H), 7.06 (d, J = 7.5 Hz, 2H), 6.29 (s, 4H), 4.34 (t, J = 8.2 Hz, 4H), 1.34 (s, 18H).

[0119] (3) Preparation of Cat.1 ligand: In a 500 mL Schlenk flask, 20 mmol of 8-bromo-6-(tert-butyl)-2,3,4,9-tetrahydro-1H-carbazole, 10 mmol of intermediate V-1, and 100 mmol of Na2CO3 were added, followed by 90 mL of toluene, 30 mL of ethanol, and 30 mL of water. After freezing and degassing three times, 1 mmol of Pd(PPh3)4 was added to the mixed solution under a N2 atmosphere, and the temperature was raised to 80 °C and stirred for 12 h. After the mixed solution was allowed to stand and separate into layers, the organic phase was collected, and the aqueous phase was extracted with dichloromethane (30 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4, and then filtered to obtain the organic phase filtrate. The solvent was removed from the filtrate by rotary evaporation, and the product was purified by column chromatography (petroleum ether: ethyl acetate = 20:1) to obtain a white solid product, which was the Cat.1 ligand, with a yield of 78%.

[0120] 1 H NMR(500MHz,Chloroform-d)δ7.60(d,J=1.6Hz,2H),7.51(d,J=1.6Hz,2H),7.41(d,J=1.6Hz,2H),7.29(dd,J=7.5,1.5Hz,2H),7.01(d,J=7.5Hz, 2H),4.40(s,2H),2.46(t,J=7.0Hz,4H),1.88(pd,J=6.9,0.7Hz,4H),1.7 8(td,J=7.1,1.0Hz,4H),1.42-1.38(m,8H),1.36(s,18H),1.31(s,18H).

[0121] (4) Preparation of Cat.1 complex: Under N2 atmosphere, 5 mmol of Cat.1 ligand and 5 mmol of HfBn2Cl2(Et2O)2 were added to 60 mL of toluene in a 200 mL Schlenk flask. The mixture was reacted at 80 °C in the dark for 12 h. The mixture was filtered and the filtrate was collected. After concentration, the mixture was placed at -18 °C to precipitate a white crystalline solid, which was the Cat.1 complex. The yield was 69%.

[0122] 1H NMR(500MHz,Chloroform-d)δ7.64(d,J=2.2Hz,2H),7.59(d,J=2.2Hz,2H),7.35(d,J=2.2Hz,2H),7.22(dd,J=6.6,2.1Hz,2H),7.02( d,J=6.6Hz,2H),4.24(t,J=7.1Hz,4H),3.14–3.07(m,4H),1.93(ddd,J=9.8,7.1,3.5Hz,4H),1.82–1.71(m,8H),1.35–1.30(m,36H).

[0123] Example 2: Preparation of Cat.2 Complex

[0124]

[0125] The crafting route for Cat.2 is as follows:

[0126]

[0127] (1) Preparation of Cat.2 ligand: In a 500 mL Schlenk flask, 20 mmol of 8-bromo-6-(tert-butyl)-1,1-dimethyl-2,3,4,9-tetrahydro-1H-carbazole, 10 mmol of intermediate V-1 and 100 mmol of Na2CO3 were added respectively. Then, 90 mL of toluene, 30 mL of ethanol and 30 mL of water were added respectively. After freezing and degassing 3 times, 1 mmol of Pd(PPh3)4 was added to the mixed solution under N2 atmosphere, and the temperature was raised to 80 °C and stirred for 12 h. After the reaction mixture was allowed to stand and separate into layers, the organic phase was collected, and the aqueous phase was extracted with dichloromethane (30 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4. The organic phase filtrate was then obtained by filtration. The solvent was removed from the filtrate by rotary evaporation, and the product was purified by column chromatography (petroleum ether: ethyl acetate = 13:1) to obtain a white solid product, which is the Cat.2 ligand, with a yield of 75%.

[0128] 1H NMR(500MHz,Chloroform-d)δ7.60(d,J=1.6Hz,2H),7.51(d,J=1.6Hz,2H),7.41(d,J=1.6Hz,2H),7.29(dd,J=7.5,1.5Hz,2H),7.01(d,J=7.5Hz, 2H),4.40(s,2H),2.46(t,J=7.0Hz,4H),1.88(pd,J=6.9,0.7Hz,4H),1.7 8(td,J=7.1,1.0Hz,4H),1.42-1.39(m,8H),1.35(s,18H),1.33(s,18H).

[0129] (2) Preparation of Cat.2 complex: Under N2 atmosphere, 5 mmol of Cat.2 ligand and 5 mmol of HfBn2Cl2(Et2O)2 were added to 60 mL of toluene in a 200 mL Schlenk flask. The mixture was reacted at 80 °C in the dark for 12 h. The mixture was filtered and the filtrate was collected. After concentration, the mixture was placed at -18 °C to precipitate a white crystalline solid, which was the Cat.2 complex. The yield was 70%.

[0130] 1 H NMR(500MHz,Chloroform-d)δ7.64(d,J=2.2Hz,2H),7.59(d,J=2.2Hz,2H),7.35(d,J=2.2Hz,2H),7.22(dd,J=6.6,2.1Hz,2H),7.02( d,J=6.6Hz,2H),4.24(t,J=8.2Hz,4H),3.14–3.07(m,4H),1.93(ddd,J=9.8,7.1,3.5Hz,4H),1.82–1.71(m,4H),1.35–1.30(m,36H).

[0131] Example 3: Preparation of Cat.3 Complex

[0132]

[0133] The crafting route for Cat.3 is as follows:

[0134]

[0135] (1) Preparation of Cat.3 ligand: In a 500 mL Schlenk flask, 20 mmol of 8-bromo-6-methoxy-1,1-dimethyl-2,3,4,9-tetrahydro-1H-carbazole, 10 mmol of intermediate V-1, and 100 mmol of Na2CO3 were added, followed by 90 mL of toluene, 30 mL of ethanol, and 30 mL of water. After freezing and degassing three times, 1 mmol of Pd(PPh3)4 was added to the mixed solution under a N2 atmosphere, and the temperature was raised to 80 °C and stirred for 12 h. After the mixed solution was allowed to stand and separate into layers, the organic phase was collected, and the aqueous phase was extracted with dichloromethane (30 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4, and then filtered to obtain the organic phase filtrate. The solvent was removed from the filtrate by rotary evaporation, and the product was purified by column chromatography (petroleum ether: ethyl acetate = 13:1) to obtain a white solid product, which was the Cat.3 ligand, with a yield of 81%.

[0136] 1 H NMR(500MHz,Chloroform-d)δ7.50(d,J=1.6Hz,2H),7.30(dd,J=7.4,1.5Hz,2H),6.93(d,J=7.5Hz,2H),6.85(d,J=1.5Hz,2H),6.77(d,J=1.4Hz,2H) ,4.40(s,2H),3.83(t,J=8.2Hz,4H),3.39(s,6H),2.51(t,J=7.0Hz,4H),1 .87(pd,J=6.8,0.9Hz,4H),1.81–1.74(m,4H),1.42(s,12H),1.37(s,18H).

[0137] (2) Preparation of Cat.3 complex: Under N2 atmosphere, 5 mmol of Cat.3 ligand and 5 mmol of HfBn2Cl2(Et2O)2 were added to 60 mL of toluene in a 200 mL Schlenk flask. The mixture was reacted at 80 °C in the dark for 12 h. The mixture was filtered and the filtrate was collected. After concentration, the mixture was placed at -18 °C to precipitate a white crystalline solid, which was the Cat.3 complex. The yield was 77%.

[0138] 1H NMR(500MHz,Chloroform-d)δ7.57(d,J=2.1Hz,2H),7.21(dd,J=6.6,2.2Hz,2H),7.16(d,J=2.2Hz,2H),7.05(d,J=2.2Hz,2H),6.89(d,J=6.6Hz,2H),3 .83(t,J=8.2Hz,4H),3.39(s,6H),3.10(t,J=8.8Hz,4H),1.93(t,J=7.1Hz, 4H), 1.86 (dtdd, J=10.0, 9.1, 7.1, 2.3Hz, 4H), 1.52 (s, 12H), 1.40 (s, 18H).

[0139] Example 4: Preparation of Cat.4 Complex

[0140]

[0141] The crafting route for Cat.4 is as follows:

[0142]

[0143]

[0144] (1) Preparation of intermediate IV-2: 50 mmol of 2-bromo-4-tert-butylphenol and 25 mmol of 1,3-dibromopropane were added to a 500 mL round-bottom flask, followed by 150 mL of acetone. After the reactants dissolved, 75 mmol of potassium hydroxide was added, and the mixture was refluxed at 60 °C for 5 h. Thin-layer chromatography (TLC) showed that the reaction was essentially complete. After removing the acetone solvent by rotary evaporation, 100 mL of DCM and 100 mL of water were added to the residue, and the organic phase was collected by extraction. The aqueous phase was extracted with DCM (50 mL × 3). After mixing all the organic phases, the mixture was dried with anhydrous Na2SO4, filtered, and the solvent was removed by rotary evaporation. The residual solid was recrystallized in acetone to obtain a white solid, which was intermediate IV-2, with a yield of 93%.

[0145] 1 H NMR (500MHz, Chloroform-d) δ7.31–7.24 (m, 4H), 6.95 (d, J = 7.5Hz, 2H), 4.18 (t, J = 7.1Hz, 4H), 2.32 (p, J = 7.1Hz, 2H), 1.33 (s, 18H).

[0146] (2) Preparation of intermediate V-2: Under a N2 atmosphere, 20 mmol of intermediate V-2 and 100 mL of ultra-dry THF were added to a 500 mL Schlenk flask. 40 mmol of n-BuLi (1.6 M hexane solution) was added dropwise at -78 °C and the reaction was carried out for 30 min. Then, 40 mmol of B(OMe)3 was added, and the temperature was slowly raised to 25 °C and the reaction was carried out for 12 h. After the reaction was completed, 80 mL of 2N HCl was added at 0 °C, and the mixture was stirred at 25 °C for 1 h. 100 mL of water was added, and the mixture was allowed to stand and separate into layers. The organic phase was collected, and the aqueous phase was extracted with EtOAc (50 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4. After filtration, the solvent was removed by rotary evaporation of the filtrate to obtain a white solid product. The white solid product was further purified by washing with n-hexane (100 mL × 3) to obtain a white solid powder, which was intermediate V-2, with a yield of 85%.

[0147] 1 H NMR(500MHz,Chloroform-d)δ7.36(d,J=1.4Hz,2H),7.28(dd,J=7.5,1.5Hz,2H),7.06(d ,J=7.5Hz,2H),6.06(s,4H),4.11(t,J=7.1Hz,4H),2.30(p,J=7.1Hz,2H),1.34(s,18H).

[0148] (3) Preparation of Cat.4 ligand: In a 500 mL Schlenk flask, 20 mmol of 8-bromo-6-(tert-butyl)-2,3,4,9-tetrahydro-1H-carbazole, 10 mmol of intermediate V-2, and 100 mmol of Na2CO3 were added, followed by 90 mL of toluene, 30 mL of ethanol, and 30 mL of water. After freezing and degassing three times, 1 mmol of Pd(PPh3)4 was added to the mixed solution under a N2 atmosphere, and the temperature was raised to 80 °C and stirred for 12 h. After the mixed solution was allowed to stand and separate into layers, the organic phase was collected, and the aqueous phase was extracted with dichloromethane (30 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4, and then filtered to obtain the organic phase filtrate. The solvent was removed from the filtrate by rotary evaporation, and the product was purified by column chromatography (petroleum ether: ethyl acetate = 19:1) to obtain a white solid product, which was the Cat.4 ligand, with a yield of 78%.

[0149] 1H NMR(500MHz,Chloroform-d)δ7.60(d,J=1.4Hz,2H),7.49(d,J=1.6Hz,2H),7.45(d,J=1.6Hz,2H),7.30(dd,J=7.5,1.5Hz,2H),7.00(d,J=7.5Hz,2H),4 .38(s,2H),4.13(t,J=7.1Hz,4H),2.78(t,J=6.9Hz,4H),2.48(t,J=6.9Hz, 4H), 2.30 (p, J = 7.1Hz, 2H), 1.92–1.77 (m, 8H), 1.36 (s, 18H), 1.31 (s, 18H).

[0150] (4) Preparation of Cat.4 complex: Under N2 atmosphere, 5 mmol of Cat.4 ligand and 5 mmol of HfBn2Cl2(Et2O)2 were added to 60 mL of toluene in a 200 mL Schlenk flask. The mixture was reacted at 80 °C in the dark for 12 h. The mixture was filtered and the filtrate was collected. After concentration, the mixture was placed at -18 °C to precipitate a white crystalline solid, which was the Cat.4 complex. The yield was 70%.

[0151] 1 H NMR (500MHz, Chloroform-d) δ7.62(d,J=2.2Hz,2H),7.53(d,J=2.1Hz,2H),7.36(d,J=2.2Hz,2H),7.20(dd,J=6.5,2.1Hz,2H),7.00(d,J=6. 6Hz,2H),4.12(t,J=8.4Hz,4H),3.20–3.02(m,4H),3.05–2.95(m,4H),2.36(p,J=8.4Hz,2H),1.81–1.70(m,8H),1.33(s,18H),1.32(s,18H).

[0152] Example 5: Preparation of Cat.5 Complex

[0153]

[0154] The crafting route for Cat.5 is as follows:

[0155]

[0156] (1) Preparation of Cat.5 ligand: In a 500 mL Schlenk flask, 20 mmol of 8-bromo-6-(tert-butyl)-1,1-dimethyl-2,3,4,9-tetrahydro-1H-carbazole, 10 mmol of intermediate V-2 and 100 mmol of Na2CO3 were added respectively. Then, 90 mL of toluene, 30 mL of ethanol and 30 mL of water were added respectively. After freezing and degassing three times, 1 mmol of Pd(PPh3)4 was added to the mixed solution under N2 atmosphere, and the temperature was raised to 80 °C and stirred for 12 h. After the reaction mixture was allowed to stand and separate into layers, the organic phase was collected, and the aqueous phase was extracted with dichloromethane (30 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4. The organic phase filtrate was then obtained by filtration. The solvent was removed from the filtrate by rotary evaporation, and the product was purified by column chromatography (petroleum ether: ethyl acetate = 16:1) to obtain a white solid product, which is the Cat.5 ligand, with a yield of 74%.

[0157] 1 H NMR(500MHz,Chloroform-d)δ7.59(d,J=1.5Hz,2H),7.52(d,J=1.4Hz,2H),7.41(d ,J=1.6Hz,2H),7.30(dd,J=7.5,1.5Hz,2H),7.01(d,J=7.5Hz,2H),4.33(s,2H),4. 13(t,J=7.1Hz,4H),2.46(t,J=7.0Hz,4H),2.30(p,J=7.1Hz,2H),1.88(pd,J=6.9, 0.7Hz, 4H), 1.78 (td, J = 7.1, 1.0Hz, 4H), 1.42 (s, 12H), 1.36 (s, 18H), 1.31 (s, 18H).

[0158] (2) Preparation of Cat.5 complex: Under N2 atmosphere, 5 mmol of Cat.5 ligand and 5 mmol of HfBn2Cl2(Et2O)2 were added to 60 mL of toluene in a 200 mL Schlenk flask. The mixture was reacted at 80 °C in the dark for 12 h. The mixture was filtered and the filtrate was collected. After concentration, the mixture was placed at -18 °C to precipitate a white crystalline solid, which was the Cat.5 complex. The yield was 73%.

[0159] 1H NMR(500MHz,Chloroform-d)δ7.64(d,J=2.2Hz,2H),7.59(d,J=2.2Hz,2H),7.35(d,J=2.2Hz,2H),7.20(dd,J=6.5,2.1Hz,2H),7.00(d,J=6.6Hz ,2H),4.12(t,J=8.4Hz,4H),3.14–3.07(m,4H),2.36(p,J=8.4Hz,2H),1 .93(ddd,J=9.9,7.1,3.5Hz,4H),1.82–1.71(m,4H),1.41–1.30(m,48H).

[0160] Example 6: Preparation of Cat.6 Complex

[0161]

[0162] The crafting route for Cat.6 is as follows:

[0163]

[0164] (1) Preparation of Cat.6 ligand: In a 500 mL Schlenk flask, 20 mmol of 8-bromo-6-methoxy-1,1-dimethyl-2,3,4,9-tetrahydro-1H-carbazole, 10 mmol of intermediate V-2, and 100 mmol of Na2CO3 were added, followed by 90 mL of toluene, 30 mL of ethanol, and 30 mL of water. After freezing and degassing three times, 1 mmol of Pd(PPh3)4 was added to the mixed solution under a N2 atmosphere, and the temperature was raised to 80 °C and stirred for 12 h. After the mixed solution was allowed to stand and separate into layers, the organic phase was collected, and the aqueous phase was extracted with dichloromethane (30 mL × 3). All organic phases were mixed and dried with anhydrous MgSO4, and then filtered to obtain the organic phase filtrate. The solvent was removed from the filtrate by rotary evaporation, and the product was purified by column chromatography (petroleum ether: ethyl acetate = 14:1) to obtain a white solid product, which was the Cat.6 ligand, with a yield of 80%.

[0165] 1H NMR(500MHz,Chloroform-d)δ7.52(d,J=1.5Hz,2H),7.30(dd,J=7.5,1.5Hz,2H) ,6.91(d,J=7.5Hz,2H),6.85(d,J=1.5Hz,2H),6.77(d,J=1.4Hz,2H),4.35(s,2H ),4.13(t,J=7.1Hz,4H),3.83(s,6H),2.51(t,J=7.0Hz,4H),2.30(p,J=7.1Hz,2 H),1.87(pd,J=6.8,0.9Hz,4H),1.81–1.74(m,4H),1.42(s,12H),1.37(s,18H).

[0166] (2) Preparation of Cat.6 complex: Under N2 atmosphere, 5 mmol of Cat.6 ligand and 5 mmol of HfBn2Cl2(Et2O)2 were added to 60 mL of toluene in a 200 mL Schlenk flask. The mixture was reacted at 80 °C in the dark for 12 h. The mixture was filtered and the filtrate was collected. After concentration, the mixture was placed at -18 °C to precipitate a white crystalline solid, which was the Cat.6 complex. The yield was 77%.

[0167] 1 H NMR(500MHz,Chloroform-d)δ7.57(d,J=2.1Hz,2H),7.21(dd,J=6.5,2.2Hz,2H), 7.16(d,J=2.2Hz,2H),7.05(d,J=2.2Hz,2H),6.89(d,J=6.6Hz,2H),4.12(t,J=8.4 Hz,4H),3.83(s,6H),3.10(t,J=8.8Hz,4H),2.36(p,J=8.4Hz,2H),1.93(ddd,J=9 .8,7.1,3.5Hz,4H),1.76(dtdd,J=10.0,9.0,7.1,2.3Hz,4H),1.44–1.33(m,30H).

[0168] Example 7: Catalysis of ethylene copolymerization with bisindolylbisphenoxy ether complex

[0169] A 250 mL stainless steel reactor equipped with a magnetic stirrer was dried at 100 °C for at least 2 hours. While still hot, a vacuum was drawn to ~2.5 mbar. Then, N2 was introduced and the reactor was purged three times with a vacuum-N2 system, followed by three purgings with a vacuum-ethylene system. Maintaining a slight positive pressure inside the reactor and a stirring speed of 500 rpm, 100 mL of 3 M norbornene / toluene solution and 1.7 mL of MAO (1.5 M toluene solution) were added sequentially. The reaction temperature was then raised to 130 °C. The pressure inside the reactor (polymerization reaction pressure) was maintained at 0.4 MPa using ethylene gas. After the reaction system stabilized, 5.0 mL of a bisindolylbisphenoxy ether complex solution (0.001 M toluene solution) was forced into the reaction system using ethylene gas to initiate the polymerization reaction. After 2 minutes of polymerization, the ethylene gas flow was stopped and ethanol quencher was added. The reactor was cooled to 60°C, and the unreacted ethylene was released. The reaction solution was then drained into 500 mL of ethanol. The polymerization product was washed three times with ethanol and then dried in a vacuum oven at 50°C until constant weight. The polymerization activity and copolymer characterization results are shown in Tables 1, 2, and 3.

[0170] Comparative Example 1: The copolymerization of ethylene and norbornene catalyzed by the 1rac-SiMe2(Ind)2ZrCl2 complex

[0171] A 250 mL stainless steel reactor equipped with a magnetic stirrer was dried at 100 °C for at least 2 hours. While still hot, a vacuum was drawn to ~2.5 mbar. Then, N2 was introduced and the reactor was purged three times with a vacuum-N2 system, followed by three purgings with a vacuum-ethylene gas system. Maintaining a slight positive pressure inside the reactor and a stirring speed of 500 rpm, 100 mL of 3 M norbornene / toluene solution and 1.7 mL of MAO (1.5 M toluene solution) were added sequentially. The reaction temperature was then raised to 130 °C. The pressure inside the reactor (polymerization reaction pressure) was maintained at 0.4 MPa using ethylene gas. After the reaction system stabilized, 5.0 mL of rac-SiMe2(Ind)2ZrCl2 complex solution (0.001 M toluene solution) was injected into the reaction system using ethylene gas to initiate the polymerization reaction. After 2 minutes of polymerization, the ethylene gas flow was stopped and ethanol quencher was added. The reactor was cooled to 60°C, and the unreacted ethylene was released. The reaction solution was then drained into 500 mL of ethanol. The polymerization product was washed three times with ethanol and then dried in a vacuum oven at 50°C until constant weight. The polymerization activity and copolymer characterization results are shown in Tables 1, 2, and 3.

[0172] Comparative Example 2Me2Si(C5Me4)(N- t Bu)TiCl2 complex catalyzes copolymerization of ethylene and norbornene

[0173] A 250 mL stainless steel reactor equipped with a magnetic stirrer was dried at 100 °C for at least 2 hours. While still hot, a vacuum was drawn to approximately 2.5 mbar. Then, N2 was introduced and the reactor was purged three times using a vacuum-N2 system, followed by three purgings using a vacuum-ethylene gas system. Maintaining a slight positive pressure within the reactor and a stirring speed of 500 rpm, 100 mL of 3 M norbornene / toluene solution and 1.7 mL of MAO (1.5 M toluene solution) were added sequentially. The reaction temperature was then raised to 130 °C. The pressure inside the reactor (polymerization reaction pressure) was maintained at 0.4 MPa using ethylene gas. After the reaction system stabilized, Me2Si(C5Me4)(N- t 5.0 mL of Bu)TiCl2 complex solution (0.001 M toluene solution) was injected into the reaction system to initiate the polymerization reaction. After 2 min of polymerization, the ethylene gas supply was stopped and ethanol quencher was added. The reactor was cooled to 60 °C, the pressure was released to remove unreacted ethylene, and the reaction solution was drained into 500 mL of ethanol. The polymerization product was washed three times with ethanol and then dried in a vacuum oven at 50 °C to constant weight. The polymerization activity and copolymer characterization results are shown in Tables 1, 2, and 3.

[0174] Table 1. Test results of copolymerization activity and polymer properties of ethylene and norbornene

[0175]

[0176] Table 2. Characterization results of polymer structure and optical properties

[0177]

[0178] Table 3. Characterization results of polymer mechanical properties

[0179]

[0180]

[0181] The results in Table 1 show that the bisindolylbisphenoxy ether complex of the present invention has excellent catalytic activity for copolymerizing ethylene and norbornene, high cyclic olefin monomer insertion rate, and a large molecular weight regulation range.

[0182] The results in Table 2 show that the COC prepared by the method described in this invention has excellent optical properties, such as good transparency (transmittance ≥90%), high refractive index (≥1.51), and high Abbe number (≥50).

[0183] The results in Table 3 show that the COC prepared by the method described in this invention has excellent mechanical properties, exhibiting excellent toughness while maintaining high mechanical strength.

[0184] Furthermore, the bisindolylbisphenoxy ether complexes described in this invention also exhibit excellent high-temperature stability, maintaining high polymerization activity and cyclic olefin monomer insertion rate even at a high reaction temperature of 130°C.

[0185] Unless otherwise specified, the terms used in this invention have the meanings commonly understood by those skilled in the art.

[0186] The embodiments described in this invention are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art can make various other substitutions, changes and improvements within the scope of this invention. Therefore, this invention is not limited to the above embodiments, but is only defined by the claims.

Claims

1. A bisindolylbisphenoxy ether complex with the structure shown in Formula I, in, M is selected from titanium, zirconium, or hafnium; R1 to R9 are each independently selected from hydrogen, substituted or unsubstituted C1 to C40 hydrocarbon groups, C3 to C40 cyclic hydrocarbon groups, C6 to C40 aryl groups, heteroatom-containing groups, or silane groups containing 1 to 3 Si atoms; multiple R1 to R9 can bond with each other to form cyclic hydrocarbon groups. X is selected from halogen, -NH2, substituted or unsubstituted C1-C20 alkyl, -NR'2, C6-C20 aryl or benzyl, wherein R' is selected from C1-C20 alkyl; Y is selected from substituted or unsubstituted C1-C20 hydrocarbon groups, C3-C20 cyclic hydrocarbon groups, hydrocarbon groups containing heteroatoms, or silane groups containing 1-3 Si atoms.

2. The bisindolylbisphenoxy ether complex according to claim 1, characterized in that, In the bisindolylbisphenoxy ether complex, R1 to R9 are each independently selected from hydrogen, C1 to C12 hydrocarbon group, C3 to C16 cyclic hydrocarbon group, C6 to C18 aryl group or a group containing heteroatoms. Preferably, R1 to R9 are each independently selected from hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, phenyl, substituted phenyl, methoxy, or multiple R1 to R9 can bond with each other to form a cyclic hydrocarbon group. X is selected from halogens, C1-C4 alkyl groups, benzyl groups, or -NR'2, wherein R' is selected from C1-C4 alkyl groups. Preferably, X is selected from halogens, including F, Cl, Br, and I.

3. The bisindolylbisphenoxy ether complex according to claim 1 or 2, characterized in that, The bisindolylbisphenoxy ether complex is preferably selected from any one of the following complexes Cat. 1 to Cat. 6: Cat.1 Cat.2 Cat.3 Cat.4 Cat.5E Cat.6 4. A method for preparing the bisindolylbisphenoxy ether complex according to any one of claims 1-3, characterized in that, Includes the following steps: S1: Synthesize phenoxy ether compound IV from compounds II and III via the Williamson reaction; S2: Compound IV is dissolved in a solvent, then alkyl lithium is added at low temperature for lithiation, followed by the addition of trimethyl borate for reaction, and then hydrolysis with hydrochloric acid aqueous solution to obtain compound V; S3: Compound V is coupled with VI, a bromide of indole or its derivative, under alkaline conditions via a Suzuki coupling reaction catalyzed by a palladium catalyst to obtain the ligand compound; S4: The ligand compound is reacted with alkyllithium to obtain a lithium salt of the ligand compound, which is then reacted with MX4 or its ether complex; or, the ligand compound is directly reacted with MR2X2 or its ether complex to obtain the bisindolylbisphenoxy ether complex.

5. The method according to claim 4, characterized in that, In formulas II and IV, X1 is selected from halogens, preferably Br; in step S2, the alkyl lithium is one or more of C1-C6 alkyl lithium, preferably one or more of methyl lithium, n-butyl lithium, and n-hexyl lithium; in formula V, Z is borate-B(OH)2; in step S4, the alkyl lithium is one or more of C1-C6 alkyl lithium, preferably one or more of methyl lithium, n-butyl lithium, and n-hexyl lithium; MX4 is selected from one or more of TiCl4, ZrCl4, and HfCl4; in step S4, R in MR2X2 is selected from C1-C20 alkyl, aryl, or benzyl, preferably ZrBn2Cl2 or HfBn2Cl2.

6. Use of the bisindolylbisphenoxy ether complex according to any one of claims 1-3 as a main catalyst for olefin polymerization.

7. The use according to claim 6, characterized in that, The olefin polymerization is a copolymerization of ethylene and / or α-olefins with cyclic olefins; Preferably, the α-olefin is a C3 to C12 α-olefin, preferably selected from one or more of 1-propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene, and the cycloolefin is a C6 to C21 cycloolefin, preferably selected from one or more of cyclohexene, norbornene, and tetracyclododecene.

8. An olefin polymerization method, comprising the following steps: in the presence of a main catalyst and a co-catalyst, ethylene and / or α-olefins react with cycloolefins to form an olefin copolymer; wherein, The main catalyst is the bisindolylbisphenoxy ether complex according to any one of claims 1-3; Preferably, the α-olefin is a C3 to C12 α-olefin, preferably selected from one or more of 1-propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene, and the cycloolefin is a C6 to C21 cycloolefin, preferably selected from one or more of cyclohexene, norbornene, and tetracyclododecene.

9. The olefin polymerization method according to claim 8, characterized in that, The molar ratio of the main catalyst to the co-catalyst is 1:1 to 5000, preferably 1:1 to 2000; and / or, The cocatalyst is selected from one or more of alkylaluminum, alkylaluminum chloride, aluminoxane, and boron-containing additives; preferably, the alkylaluminum is selected from one or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, and tri-n-octylaluminum; the alkylaluminum chloride is selected from one or more of diethylaluminum chloride, diethylaluminum chloride, and sesqui-diethylaluminum chloride; the aluminoxane is selected from one or more of methylaluminoxane, ethylaluminoxane, and isobutylaluminoxane; and the boron-containing additive is selected from one or two of tris(pentafluorophenyl)borane and triphenylcarbazone(pentafluorophenyl)borate. More preferably, the co-catalyst is selected from methylaluminoxane or a combination of methylaluminoxane and triisobutylaluminum in a molar ratio of 1 to 50:1, preferably 2 to 30:

1.

10. The olefin polymerization method according to claim 8 or 9, characterized in that, The polymerization reaction temperature is 50–200°C, preferably 90–180°C; and / or, the polymerization reaction pressure is 0.01–10 MPa, preferably 0.1–3 MPa; and / or, the polymerization reaction time is 0.1–1000 min, preferably 1–100 min.

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