Ligand compounds containing a benzamidine group, metal complexes, metal-supported catalysts and use thereof

Abstract

This invention relates to a ligand compound containing a benzylamide group, a metal complex, a metal-supported catalyst, and their applications, belonging to the field of catalytic olefin polymerization and synthesis of high-molecular-weight polyolefins. The ligand compound has the structural formula shown in Formula I, wherein R2, R3, R4, and R5 are independently selected from C1 to C5. 10 The alkyl group, substituted or unsubstituted diphenylmethyl group, and hydrogen are all selected from the group; R1 and R6 are simultaneously selected from the group consisting of methoxy, hydroxyl, and sodium oxyalkylene substituents; when there are substituents on the diphenylmethyl group, the substituents are selected from hydroxyl, C1 to C6. 10 Alkyl groups, C1-C 10 alkoxy groups, C2-C 10 Any of the alkenyl groups. This invention links the R1 and R6 groups to the benzene-2,000 skeleton, so that during subsequent loading, the R1 and R6 groups can form strong hydrogen bond interactions with the hydrogen atoms on the support. Combined with the steric hindrance effect regulated by the benzene-2,000 skeleton, the subsequently prepared metal-supported catalyst has better catalytic performance.

Description

Technical Field

[0001] This invention relates to the field of catalytic olefin polymerization and synthesis of high molecular weight polyolefin materials, specifically to a ligand compound containing a benzylamide group, a metal complex, a metal-supported catalyst, and their applications. Background Technology

[0002] Polyolefin materials constitute a significant proportion of synthetic polymers, playing a crucial role in various aspects of daily life. Due to the inertness of their chemical bonds, non-functionalized polyolefins exhibit considerable advantages in solvent resistance and thermal stability. However, polyolefins typically suffer from poor adhesion, poor dyeability, and poor rheological and blending properties. To broaden the application range of polyolefin materials, research into functionalized polyolefin materials has been a focus of attention and exploration in both academia and industry.

[0003] Currently, the industry mainly introduces polar functional groups into polyolefin materials through high-temperature, high-pressure free radical polymerization, ionic polymerization, or post-polymerization modification. These methods typically involve demanding conditions and relatively poor controllability, making it difficult to achieve molecular-level regulation of the polymer. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a ligand compound containing a benzilamide group, a metal complex, a metal-supported catalyst, and their applications. By introducing methoxy, hydroxy, or sodium oxydioxide substituents onto the benzilamide group, the oxygen atoms in these groups can form strong hydrogen bond interactions with the hydrogen atoms on the support during subsequent loading, resulting in a metal-supported catalyst with high stability and activity.

[0005] According to one aspect of the present invention, a ligand compound of formula I containing a benzamide group is provided, wherein R1 and R6 are simultaneously selected from any one of methoxy, hydroxy, and sodium oxosubstituents; and R2, R3, R4, and R5 are each independently selected from C1 to C5. 10 The diphenylmethyl group consists of any one of alkyl, substituted or unsubstituted diphenylmethyl, and hydrogen; when there is a substituent on the diphenylmethyl group, the substituent is selected from hydroxyl, C1-C1, C2-C4, C3-C4, C4-C4, C3 ... 10 Alkyl groups, C1-C 10 alkoxy groups, C2-C 10 Any one of the alkenyl groups.

[0006]

[0007] According to some embodiments of the present invention, R2, R3, R4, and R5 are each independently selected from one of the following structures:

[0008]

[0009] According to some embodiments of the present invention, R2, R3, R4, and R5 are all isopropyl, and R1 and R6 are both hydroxyl or methoxy.

[0010] According to some embodiments of the present invention, the above-mentioned ligand compounds include compounds with structures shown in Formulas I1 to I9:

[0011]

[0012]

[0013] According to another aspect of the present invention, a metal complex of formula II is provided, wherein M is nickel or palladium, X is Cl or Br; R1 and R6 are simultaneously selected from any one of methoxy, hydroxy, and sodium oxyalkylene substituents; and R2, R3, R4, and R5 are each independently selected from C1 to C2. 10 The diphenylmethyl group consists of any one of alkyl, substituted or unsubstituted diphenylmethyl, and hydrogen; when there is a substituent on the diphenylmethyl group, the substituent is selected from hydroxyl, C1-C1, C2-C4, C3-C4, C4-C4, C3 ... 10 Alkyl groups, C1-C 10 alkoxy groups, C2-C 10 Any one of the alkenyl groups.

[0014]

[0015] According to some embodiments of the present invention, R2, R3, R4, and R5 are each independently selected from one of the following structures:

[0016]

[0017] According to some embodiments of the present invention, the above-mentioned ligand compounds include compounds with structures shown in Formulas II1 to II9:

[0018]

[0019]

[0020] According to another aspect of the present invention, a metal-supported catalyst is provided, which is prepared using the above-described metal complex and support, wherein the metal complex is supported on the support.

[0021] According to some embodiments of the present invention, the carrier includes at least one of silicon dioxide, magnesium chloride, and aluminum oxide.

[0022] According to another aspect of the present invention, the above-described metal-supported catalyst is provided for catalyzing C2-C2 catalysts. 11 Applications of olefin monomers in polymerization reactions.

[0023] According to some embodiments of the present invention, catalyzing C2-C 11 The polymerization reactions of olefin monomers include:

[0024] The co-catalyst and C2~C 11 The olefin monomers are added to an organic solvent, and then a metal-supported catalyst is injected, allowing C2-C2 olefins to be oxidized. 11 The olefin monomers undergo coordination polymerization; wherein the organic solvent includes at least one of toluene, benzene, and n-heptane; the co-catalyst includes at least one of trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum chloride, dichloroethylaluminum, tri-n-butylaluminum, an alkali metal, or a base metal salt; C2-C 11 The olefin monomers include at least one of methacrylic acid, methyl methacrylate, ethyl methacrylate, 10-undecenol, 10-undecenic acid, 6-chloro-1-hexene, 1-hexene, and 1-octene.

[0025] Based on the above technical solutions, the ligand compounds containing benzamide groups, metal complexes, metal-supported catalysts, and their applications of the present invention have at least one or a portion of the following beneficial effects:

[0026] The ligand compound of this invention has a benzoinamide skeleton, exhibiting moderate ligand activity as a metal catalyst. The simultaneous introduction of methoxy, hydroxyl, or sodium oxosubstituents at relative positions on the benzoinamide skeleton ensures that, during subsequent loading, the oxygen atoms in these groups on the resulting metal-supported catalyst carry a negative charge. The lone pair electrons of the oxygen atoms can form hydrogen bonds with the nuclei of hydrogen atoms on the support, thereby making the bond between the ligand compound and the support more stable and achieving better loading effects. This results in a metal-supported catalyst with higher stability and activity compared to homogeneous catalysts, enabling the preparation of polyolefins with higher molecular weight and better morphological control. Furthermore, the heterogeneous metal-supported catalyst exhibits higher tolerance to polar monomers during subsequent olefin polymerization, making it easier for olefins to copolymerize with polar monomers. The resulting polyolefins do not stick to the reactor and are easier to industrialize. Simultaneously, the benzoinamide skeleton can create a significant steric hindrance effect, confining the intercalated metal to a smaller spatial range when coordinating with nitrogen, thereby reducing uncontrollable chain walk and chain transfer behavior of the metal center. The combined effect of the benzamide backbone and the hydrogen bonds between it and the support makes it easier to increase the molecular weight of polyolefins and reduce the degree of branching during subsequent olefin polymerization. Attached Figure Description

[0027] The present invention will be further described in detail below with reference to the accompanying drawings.

[0028] Figure 1The 1H NMR spectrum of ligand compound 1 prepared in Example 1 of this invention;

[0029] Figure 2 The above is the 1H NMR spectrum of ligand compound 2 prepared in Example 2 of this invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0031] The endpoints and any values ​​of the ranges invented in this invention 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 the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically invented in this invention.

[0032] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0033] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0034] Similarly, to simplify the invention and aid in understanding one or more aspects of the invention, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. The use of terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples" indicates that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0036] Related technologies often use free radical polymerization, ionic polymerization, or post-polymerization modification to introduce polar functional groups. These methods have relatively harsh conditions and the resulting polyolefins have poor controllability, making it difficult to regulate the morphology of the prepared polyolefins.

[0037] In the process of developing this invention, it was discovered that designing a skeleton containing benzodiazepine and applying it to olefin polymerization involves simultaneously attaching methoxy, hydroxy, or sodium oxydioxide substituents at the para position of the benzodiazepine skeleton. Through the strong hydrogen bond interaction formed between the oxygen atoms on the above groups and the hydrogen atoms on the support, the prepared ligand compound exhibits higher stability and activity after loading compared to the unloaded state, enabling the preparation of polyolefins with high molecular weight and good morphology control.

[0038] According to one aspect of the present invention, a ligand compound of formula I containing a benzylamide group is provided, wherein R2, R3, R4, and R5 are each independently selected from C1 to C5. 10 The alkyl group, substituted or unsubstituted diphenylmethyl group, and hydrogen are selected from any one of the following: R1 and R6 are simultaneously selected from any one of the following: methoxy, hydroxyl, and sodium oxyalkylene substituents; wherein, when there is a substituent on the diphenylmethyl group, the substituent is selected from hydroxyl, C1 to C6. 10 Alkyl groups, C1-C 10 alkoxy groups, C2-C 10 Any one of the alkenyl groups.

[0039]

[0040] According to some embodiments of the present invention, the ligand compound shown in Formula I has a benzodiazepine skeleton, exhibiting moderate ligand activity as a metal catalyst. By simultaneously introducing methoxy, hydroxyl, and sodium oxydioxide substituents at the para-position of the benzodiazepine skeleton, when subsequently loaded to form a metal-supported catalyst, firstly, the benzodiazepine skeleton creates a large steric hindrance effect, confining the inserted metal to a small spatial range when coordinating with nitrogen, thereby reducing uncontrollable chain walk and chain transfer behavior of the metal center. Secondly, hydrogen bonding interactions are formed between the oxygen atoms in the above-mentioned groups and the hydrogen atoms on the support, making the binding between the ligand compound and the support more stable and achieving a better loading effect. By introducing the above-mentioned groups at the para-position of the benzodiazepine skeleton, the prepared metal-supported catalyst has high stability and activity, and can produce polyolefins with high molecular weight and good morphological control during subsequent olefin polymerization. Furthermore, the heterogeneous metal-supported catalyst prepared subsequently exhibits high tolerance to polar monomers during olefin polymerization, making it easier for olefins to copolymerize with polar monomers. The resulting polyolefins do not stick to the reactor and are easier to industrialize.

[0041] According to some embodiments of the present invention, R2, R3, R4, and R5 are each independently selected from one of the following structures:

[0042]

[0043] During the preliminary experiments related to this invention, it was found that when R2, R3, R4, and R5 are selected from the above groups, the degree of branching of the subsequently prepared olefin polymer is lower and the molecular weight is higher.

[0044] Preferably, R2, R3, R4, and R5 are all isopropyl, and R1 and R6 are both hydroxyl or methoxy.

[0045] According to some embodiments of the present invention, the above-mentioned ligand compounds include compounds with structures shown in Formulas I1 to I9:

[0046]

[0047]

[0048] According to some embodiments of the present invention, a method for preparing a ligand compound containing a benzamide group of formula I is also provided, comprising: dissolving the compound represented by formula A, the compound represented by formula B, and the compound represented by formula C in a first solvent, and adding formic acid catalyst and heating under reflux. After the reaction is completed, the reaction solution is concentrated, and anhydrous diethyl ether is added, resulting in the precipitation of a yellow-green solid in the reaction solution. The yellow-green solid is separated by filtration, and then washed and dried sequentially to obtain the compound represented by formula I.

[0049]

[0050] The reaction process is shown below:

[0051]

[0052] According to some embodiments of the present invention, the reaction conditions for preparing the compound represented by Formula I are as follows: at 70–90°C, for example, 70°C, 75°C, 80°C, 85°C, or 90°C, preferably 80°C. The heating and reflux time is 10–14 h, for example, 10 h, 11 h, 12 h, 13 h, or 14 h, preferably 12 h.

[0053] According to some embodiments of the present invention, the first solvent includes methanol or toluene.

[0054] According to some embodiments of the present invention, the molar ratio of the compound represented by Formula A, the compound represented by Formula B, and the compound represented by Formula C is 1:1:1.

[0055] According to some embodiments of the present invention, the compounds shown in Formula A, Formula B, and Formula C can be purchased and used directly.

[0056] According to embodiments of the present invention, a metal complex of formula II is also provided, wherein M is nickel or palladium, X is Cl or Br; R1 and R6 are simultaneously selected from any one of methoxy, hydroxy, and sodium oxydioxide substituents; and R2, R3, R4, and R5 are each independently selected from C1 to C2. 10 The diphenylmethyl group consists of any one of alkyl, substituted or unsubstituted diphenylmethyl, and hydrogen; when there is a substituent on the diphenylmethyl group, the substituent is selected from hydroxyl, C1-C1, C2-C4, C3-C4, C4-C4, C3 ... 10 Alkyl groups, C1-C 10 alkoxy groups, C2-C 10 Any one of the alkenyl groups.

[0057]

[0058] According to some embodiments of the present invention, the formed metal complex utilizes a benzylamide backbone to create a large steric hindrance effect, thereby suppressing the spatial range of metal-nitrogen coordination and reducing uncontrollable chain walk and chain transfer at the metal center. This is beneficial for increasing the molecular weight of polyolefins and reducing the degree of branching during subsequent olefin polymerization.

[0059] According to some embodiments of the present invention, R2, R3, R4, and R5 are each independently selected from one of the following structures:

[0060]

[0061] During the preliminary experiments related to this invention, it was found that when R2, R3, R4, and R5 are selected from the above groups, the degree of branching of the subsequently prepared olefin polymer is lower and the molecular weight is higher.

[0062] According to some embodiments of the present invention, the above-mentioned nickel complex includes compounds with structures shown in Formulas II1 to II9:

[0063]

[0064]

[0065] According to some embodiments of the present invention, a method for preparing a metal complex of formula II is also provided, comprising: adding the compound of formula I and (DME)NiBr2 (DME is 1,2-dimethoxyethane) to a first organic solvent under anhydrous and oxygen-free conditions, mixing and stirring, and then sequentially filtering, recrystallizing, filtering and drying to prepare the metal complex of formula II.

[0066] The reaction process is shown below:

[0067]

[0068] According to some embodiments of the present invention, the molar ratio of the compound represented by Formula I to (DME)NiBr2 is 1:1.

[0069] According to some embodiments of the present invention, the reaction conditions for preparing the compound represented by Formula II are as follows: at 5 to 25°C, for example, 5°C, 10°C, 15°C, 20°C, or 25°C. The mixing and stirring time is 10 to 14 hours, for example, 10 hours, 11 hours, 12 hours, 13 hours, or 14 hours, preferably 12 hours.

[0070] According to some embodiments of the present invention, a metal-supported catalyst is also provided, comprising the metal complex and the support as described above, wherein the metal complex is supported on the support.

[0071] According to some embodiments of the present invention, the oxygen atom from the methoxy, hydroxy, and sodium oxydioxide substituents introduced simultaneously at the para position of the benzylamide skeleton can form a strong hydrogen bond interaction with the hydrogen atoms on the support, thereby increasing the active sites on the support surface. This allows the metal-supported catalyst to be in closer contact with the support, resulting in a better loading effect and forming a heterogeneous supported catalyst with excellent catalytic performance.

[0072] According to some embodiments of the present invention, the carrier includes at least one of silicon dioxide, magnesium chloride or aluminum oxide, preferably silicon dioxide.

[0073] According to some embodiments of the present invention, a method for preparing a metal-supported catalyst is also provided, comprising: adding the metal complex shown in Formula II and the support to a second solvent at room temperature and stirring for 8 to 16 hours, followed by filtration and drying to obtain the metal-supported catalyst.

[0074] According to some embodiments of the present invention, the second solvent includes dichloromethane or tetrahydrofuran.

[0075] According to some embodiments of the present invention, a metal-supported catalyst as described above is also provided for catalyzing C2-C2 catalysts. 11 Applications of olefin monomers in polymerization reactions.

[0076] According to some embodiments of the present invention, the polymerization reaction includes C2 to C3. 11 Homopolymerization and / or copolymerization of olefin monomers.

[0077] Specifically, when the polymerization reaction is a homopolymerization reaction of C2 to C4 olefin monomers, C2 to C4 olefin monomers, co-catalysts and organic solvents are added to the reaction vessel and mixed evenly. A metal-supported catalyst is added, and the homopolymerization reaction is carried out under a pressure of 1 to 50 atmospheres. After the reaction is completed, quenching is performed.

[0078] When the polymerization reaction is the homopolymerization of long-chain olefins with C5 or more, the other conditions are the same as those for the homopolymerization reaction described above. The difference is that the homopolymerization of long-chain olefins needs to be carried out in an inert gas atmosphere.

[0079] When the polymerization reaction is a copolymerization reaction of C2 to C4 olefin monomers, the C2 to C4 olefin comonomer, cocatalyst and organic solvent are added to the reaction vessel and mixed evenly. A metal-supported catalyst is added, and the copolymerization reaction is carried out under a pressure of 1 to 50 atmospheres. After the reaction is completed, quenching is performed.

[0080] According to some embodiments of the present invention, the reagent used during quenching includes methanol.

[0081] According to some embodiments of the present invention, catalyzing C2-C 11 The polymerization reaction of olefin monomers includes: using a co-catalyst and C2-C2O4... 11 The olefin monomers are added to an organic solvent, and then a metal-supported catalyst is introduced, allowing C2-C2 olefins to precipitate. 11 The olefin monomers undergo coordination polymerization. The organic solvent includes at least one of toluene, benzene, and n-heptane. The co-catalyst includes at least one of trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum chloride, dichloroethylaluminum, tri-n-butylaluminum, an alkali metal, and an alkali metal salt. C2~C 11The olefin monomers include at least one selected from methacrylic acid, methyl methacrylate, ethyl methacrylate, 10-undecenol, 10-undecenic acid, 6-chloro-1-hexene, 1-hexene, and 1-octene. During the screening of organic solvents, co-catalysts, and olefin monomers, it was found that when the organic solvent, co-catalyst, and olefin monomer were selected from the specific compounds listed above, the resulting polymer products had higher molecular weights, stronger activity, and lower branching degrees.

[0082] In a typical experiment, taking the homopolymerization of ethylene as an example, the specific preparation steps are as follows:

[0083] In a glove box, 500 eq of dichloroethylaluminum (AlEt2Cl), 18 mL of n-hexane, and a magnetic stir bar were added to a 350 mL thick-walled glass pressure vessel. The pressure vessel was then connected to a high-pressure line, and the solution was degassed. The vessel was heated to 20–40 °C using an oil bath and allowed to equilibrate for 15 minutes. 5 μmol of the metal complex or 5 μmol of the metal-supported catalyst in 2 mL of CH2Cl2 was injected into the polymerization system via a syringe. The reactor was pressurized under rapid stirring and maintained at 8.0 atm of ethylene. After the required time, the pressure vessel was vented, and the polymer was precipitated in acidified methanol (methanol / HCl = 50 / 1) and dried under vacuum at 50 °C for 24 hours.

[0084] In a typical experiment, taking undecenoic acid copolymerization as an example, the specific preparation steps are as follows:

[0085] In a glove box, a total of 18 mL of 500 eq AlEt2Cl, n-hexane, and undecenoic acid, along with a magnetic stir bar, were added to a 350 mL thick-walled glass pressure vessel. The pressure vessel was then connected to a high-pressure line, and the solution was degassed. The vessel was heated to 20–40 °C using an oil bath and allowed to equilibrate for 15 minutes. 15 μmol of the metal complex or 15 μmol of the metal-supported catalyst in 2 mL of CH2Cl2 was injected into the polymerization system using a syringe. The reactor was pressurized under rapid stirring and maintained at 8.0 atm of ethylene. After 30 minutes, the solvent was evaporated, and the polymer was vacuum-dried at 50 °C for 24 hours.

[0086] The present invention will be further illustrated by the following embodiments. In the detailed description below, numerous specific details are set forth for ease of explanation to provide a comprehensive explanation of the embodiments of the present invention. However, it will be apparent that one or more embodiments may be practiced without these specific details. Moreover, the details in the following embodiments can be arbitrarily combined to form other feasible embodiments without conflict.

[0087] It should be noted that the following embodiments illustrate the specific content of the present invention, and the data given include the synthesis of ligands, the synthesis of metal compounds, and methods for ethylene polymerization or copolymerization. The synthesis of complexes and polymerization processes are all carried out under anhydrous and oxygen-free conditions. All sensitive substances are stored in a glove box, all solvents are strictly dried and dehydrated, and ethylene gas is purified by passing it through a dehydration and deoxygenation column. Unless otherwise specified, all raw materials are used directly after purchase. The methods used in the following embodiments, such as immunofluorescence staining, are methods well-known in the art and can be described in textbooks or relevant literature, and will not be elaborated further.

[0088] In this embodiment of the invention, NMR detection was performed using a Bruker 400MHz NMR instrument, elemental analysis was performed by the Physics and Chemistry Center of the University of Science and Technology of China, molecular weight and molecular weight distribution were determined by high-temperature GPC, and mass spectrometry was performed using a Thermo LTQOrbitrap XL.

[0089] Example 1:

[0090] Synthesis of ligand compound 1:

[0091] 2 mmol of aniline and 2 mmol of methylbenzoyl (2 mmol) were added with a few drops of formic acid (1 mL) to 20 mL of methanol solution, and refluxed at 80 °C for 12 hours until a new product spot formed on a thin-layer chromatography (TLC) plate. The remaining mixture was diluted in 30 mL of diethyl ether and stirred for 1 hour. The pale yellow solid was separated by filtration, which was ligand compound 1, with a product yield of 73%. Figure 1 The 1H NMR spectrum of ligand compound 1 prepared in Example 1 of this invention is shown below. Figure 1 The structure of the prepared product can be determined as shown. 1 H NMR (400MHz, CDCl3) δ7.45,7.04,6.99,6.97,6.95,6.93,6.92,6.91,6.89,6.88,6.87,6.86, 6.85,6.55,6.53,6.52,6.45,6.44,6.43,3.86,3.66,3.14,3.12,3.10,3.09,3.07,2.50,2.4 8,2.46,2.45,2.43,2.22,2.20,2.20,2.18,2.17,2.15,2.14,2.12,2.10,2.08,1.30,1.28,1.26,1.22,1.08,1.07,1.06,1.04,1.02,1.00,0.92,0.91,0.90,0.89,0.88,0.87,0.61,0.60.

[0092] The reaction process is shown below:

[0093]

[0094] Synthesis of nickel complex Ni1:

[0095] Under a nitrogen atmosphere, 1 mmol of ligand compound 1, 1 mmol of (DME)NiBr2, and 10 mL of dichloromethane were added to a 50 mL Schlenk flask. After stirring at room temperature for 12 hours, the product was precipitated with n-hexane, separated by filtration, and dried under vacuum to give a pale yellow solid nickel complex Ni1 in 78% yield.

[0096] The reaction process is shown below:

[0097]

[0098] Example 2:

[0099] Synthesis of ligand compound 2:

[0100] Under a nitrogen atmosphere, 10.00 mmol of ligand compound 1 was dissolved in 30 mL of dry dichloromethane and placed in an ice-water bath at -30 °C. 20.00 mmol of boron tribromide was added, and the reaction was carried out for 4 hours. Then, 10 mL of water was added, and the reaction was allowed to proceed overnight at room temperature. After the reaction was complete, the solvent was dried under vacuum, and the mixture was extracted with water and ethyl acetate. The organic phase was dried and filtered. The filtrate was collected, evaporated to dryness, and recrystallized from petroleum ether to obtain a grayish-yellow solid powder, which was ligand compound 2. Figure 2 The 1H NMR spectrum of ligand compound 2 prepared in Example 2 of this invention is shown below. Figure 2 The structure of the prepared product can be determined as shown. 1 H NMR (400MHz, MeOD) δ8.10–8.05,7.86,7.48,7.39–7.22,6.81,6.68,3.05–2.95,1.25,1.02.

[0101] The reaction process is shown below:

[0102]

[0103] Synthesis of nickel complex Ni2:

[0104] Under a nitrogen atmosphere, 1 mmol of ligand compound 2, 1 mmol of (DME)NiBr2, and 10 mL of dichloromethane were added to a 50 mL Schlenk flask. After stirring at room temperature for 8 hours, the product was precipitated with n-hexane, separated by filtration, and dried under vacuum to give a red solid nickel complex Ni2 in 84% yield.

[0105] The reaction process is shown below:

[0106]

[0107] Example 3:

[0108] Synthesis of ligand compound 3:

[0109] Under a nitrogen atmosphere, 10.00 mmol of ligand compound 2 was dissolved in 30 mL of dry tetrahydrofuran and placed in an ice-water bath at -10 °C. 20.00 mmol of sodium hydride was added and the reaction was carried out for 1 hour. The reaction was completed by drying the solvent at room temperature to obtain ligand compound 3.

[0110] The reaction process is shown below:

[0111]

[0112] Synthesis of nickel complex Ni3:

[0113] Under a nitrogen atmosphere, 1 mmol of ligand compound 3, 1 mmol of (DME)NiBr2, and 10 mL of tetrahydrofuran were added to a 50 mL Schlenk flask. After stirring at room temperature for 8 hours, the product was precipitated with n-hexane, separated by filtration, and dried under vacuum to give a blue solid nickel complex Ni3 in 78% yield.

[0114] The reaction process is shown below:

[0115]

[0116] Example 4:

[0117] Synthesis of supported nickel catalyst Ni2@SiO2:

[0118] The 2 μmol of nickel complex Ni2 prepared in Example 2, 100 mg of silicon dioxide and 15 ml of dichloromethane were stirred in a glove box at 20 °C for 12 h. After filtration and drying of the filter residue, a light yellow solid Ni2@SiO2 was obtained.

[0119] Example 5:

[0120] Synthesis of supported nickel catalyst Ni3@SiO2:

[0121] The nickel complex Ni3 prepared in Example 3, 5 μmol, 100 mg of silicon dioxide, and 15 ml of dichloromethane were stirred in a glove box at 20 °C for 12 h. After filtration and drying of the filter residue, a light orange solid Ni3@SiO2 was obtained.

[0122] The effects of the benzamide-based nickel catalysts prepared in Examples 1-5 on the homopolymerization of ethylene before and after loading were tested.

[0123] In a glove box, 500 eq of AlEt2Cl, 18 mL of n-hexane, and a magnetic stir bar were loaded into a 350 mL thick-walled glass pressure vessel. The pressure vessel was connected to a high-pressure line, and the solution was degassed. The vessel was heated to the desired temperature using an oil bath and allowed to equilibrate for 15 minutes. The benzo[a]amide-based nickel catalysts prepared in Examples 1-5 above, before and after loading, were injected into the polymerization system using a syringe in 2 mL of CH2Cl2. The reactor was pressurized under rapid stirring and maintained at 8.0 atm for ethylene. After 30 min, the pressure vessel was vented, and the polymer was precipitated in acidified methanol (methanol / HCl = 50 / 1) and dried under vacuum at 50 °C for 24 hours. The data for the ethylene homopolymers catalyzed by different catalysts are shown in Table 1 below.

[0124] Table 1. Ethylene Homopolymer Table a

[0125]

[0126] a Polymerization conditions: Ni:AlEt2Cl (500 equivalents), ethylene pressure of 8 atm, 30 min. b Activity at 10 6 gmol -1 h -1 Units. c Molecular weight of 10 4 gmol -1 The unit is polystyrene. The determination was performed in trichlorobenzene using gel permeation chromatography (GPC) at 150°C using polystyrene standards. d The degree of branching is given per 1000 carbon atoms. The number of branches per 1000 C atoms = (CH3 / 3) / [(CH+CH2+CH3) / 2]*1000. e The determination was performed using differential scanning calorimetry (DSC, with secondary heating).

[0127] The effects of the nickel catalysts containing benzamide prepared in Examples 1-5 on the copolymerization reaction of ethylene and polar monomers before and after loading were tested.

[0128] In a glove box, a total of 18 mL of 1500 eq AlEt2Cl, n-hexane, and undecenoic acid, along with a magnetic stir bar, were loaded into a 350 mL thick-walled glass pressure vessel. The pressure vessel was connected to a high-pressure line, and the solution was degassed. The vessel was heated to the desired temperature using an oil bath and allowed to equilibrate for 15 minutes. 15 μmol of the metal complex or 15 μmol of the metal-supported catalyst in 2 mL of CH2Cl2 was injected into the polymerization system using a syringe. The reactor was pressurized under rapid stirring and maintained at 2.0 atm for ethylene. After 30 min, the solvent was evaporated, and the polymer was vacuum-dried at 50 °C for 24 h. The copolymerization data of ethylene and undecenoic acid catalyzed by different catalysts are shown in Table 2 below.

[0129] Table 2. Copolymerization of Ethylene and Undecenoic Acid a

[0130]

[0131] a Polymerization conditions: Ni catalyst (15 μmol), AlEt2Cl (1500 equivalents), undecenoic acid (1 M), n-hexane (20 mL), ethylene pressure 2 atm, 30 min. b The active unit is 10 5 gmol -1 h -1 . c Calculated based on the ratio of the obtained polymer to the original 1-undecenoic acid feed, using 1 H NMR determination. d Molecular weight of 10 4 gmol -1 The unit is polystyrene. The determination of polystyrene in trichlorobenzene was performed at 150°C using gel permeation chromatography (GPC). e The determination was performed using differential scanning calorimetry (DSC, with secondary heating).

[0132] The results in Tables 1 and 2 show that the heterogeneous supported catalyst exhibits higher catalytic activity than the homogeneous catalyst, resulting in higher molecular weight and lower branching degree of the prepared polyethylene and ethylene-undecenoic acid. Furthermore, the supported catalyst prepared in this invention is less prone to sticking to the reactor compared to the homogeneous catalyst.

[0133] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A metal-supported catalyst, comprising a metal complex and a support, wherein the metal complex is supported on the support, and the metal complex has the structural formula shown in formula (II): Formula (II) in, X is either Cl or Br; R1 and R6 are both selected from either hydroxyl or sodium oxosubstituent; R2, R3, R4, and R5 are each independently selected from C1 to C2. 10 Alkyl groups.

2. The metal-supported catalyst according to claim 1, wherein, The carrier includes at least one of silicon dioxide, magnesium chloride, and aluminum oxide.

3. The metal-supported catalyst according to claim 1, wherein, R2, R3, R4, and R5 are each independently selected from one of the following structures: 。 4. The metal-supported catalyst according to claim 3, wherein, The metal complex has a structure shown in any one of formulas (II1) to (II9): Formula (Ⅱ1) Formula (Ⅱ2) Formula (Ⅱ3) Formula (Ⅱ7) Formula (Ⅱ8) Formula (Ⅱ9).

5. The metal-supported catalyst according to claim 1, wherein, The metal complex is formed by coordination of a ligand compound containing a benzamide group, the ligand compound having the structural formula shown in formula (I): Equation (I) Among them, R2, R3, R4, and R5 are independently selected from C1 to C2. 10 Alkyl groups; R1 and R6 are both selected from either hydroxyl or sodium oxygenate substituents.

6. The metal-supported catalyst according to claim 5, wherein, The ligand compound has a structure shown in any one of formulas (I2) to (I9): Equation (I2), Equation (I3) Formula (I5) Equation (I6) Formula (I8) Formula (I9).

7. A metal-supported catalyst as described in any one of claims 1-6 for catalyzing C2~C2 ... 11 Applications of olefin monomers in polymerization reactions.

8. The application according to claim 7, wherein, The catalyst C2~C 11 The polymerization reactions of olefin monomers include: catalyst and C2~C 11 The olefin monomer is added to an organic solvent, and then the metal-supported catalyst is injected, so that C2~C 11 The olefin monomers undergo coordination polymerization reactions; The organic solvent includes at least one of toluene, benzene, and n-heptane; The co-catalyst includes at least one of trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum chloride, dichloroethylaluminum, tri-n-butylaluminum, alkali metal or base metal salt; The C2~C 11 The olefin monomers include at least one of methacrylic acid, methyl methacrylate, ethyl methacrylate, 10-undecenol, 10-undecenic acid, 6-chloro-1-hexene, 1-hexene, and 1-octene.

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