Alpha-diimine ligand compounds, alpha-diimine nickel catalysts, and methods of making and using the same

Abstract

The application provides an alpha-diketiminate ligand compound, an alpha-diketiminate nickel catalyst and a preparation method and application thereof, and belongs to the technical field of organic synthesis. The alpha-diketiminate ligand compound has a structure as shown in the formula (I): formula (I); wherein R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; and R3 is selected from hydrogen or methyl. The alpha-diketiminate nickel catalyst prepared by using the alpha-diketiminate ligand compound can catalyze olefins to perform homopolymerization or copolymerization, not only excellent catalytic performance is exhibited, but also the polyolefin material obtained by catalyzing the homopolymerization of olefin monomers has excellent elastic recovery performance, and has certain application potential in the olefin polymerization industry.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis technology, and relates to an α-diimine ligand compound, an α-diimine nickel catalyst, its preparation method and application, and more specifically to an α-diimine ligand compound containing a methoxy structure, an α-diimine nickel catalyst, its preparation method and application as a nickel catalyst. Background Technology

[0002] Nickel α-diimine catalysts, as olefin polymerization catalysts, occupy an important position in the field of polyolefin material preparation due to their simple synthesis, relatively low cost, and unique "chain-walking" mechanism. By controlling the structure of the ligand backbone and the substituents on the aniline ring, the activity, thermal stability, and microstructure and macroscopic properties (such as molecular weight, degree of branching, and topological morphology) of the resulting polymer can be significantly affected. Therefore, the structural design of α-diimine ligand compounds and nickel α-diimine catalysts is of great research significance and application value for developing polyolefin catalysts with higher catalytic performance.

[0003] Current research focuses on modifying the substituents on the aniline ring of α-diimine ligand compounds with alkyl groups (such as methyl and isopropyl), halogens, or sterically hindered aryl groups. While these substituents can improve the stability of α-diimine nickel catalysts to some extent and specifically regulate the branching structure of polymers, they still have several shortcomings: First, although traditional sterically hindered substituents can inhibit chain transfer reactions and increase polymer molecular weight, they often lead to a decrease in the activity of α-diimine nickel catalysts and are not conducive to the preparation of polyolefin materials with higher branching degrees or elastic properties; Second, the catalytic stability of existing catalytic systems under high-temperature (≥70℃) polymerization conditions and their tolerance to polar monomers are limited, restricting their application in the field of polyolefin functionalization modification. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides an α-diimine ligand compound, an α-diimine nickel catalyst, its preparation method, and its application. The introduction of the methoxy structure not only increases the axial steric hindrance of the nickel metal center in the α-diimine nickel catalyst but also affects the electronic environment of the nickel metal center, thereby significantly improving the catalytic effect of the α-diimine nickel catalyst.

[0005] As a first aspect of the present invention, an α-diimine ligand compound is provided having a structure as shown in formula (I):

[0006] Formula (I);

[0007] R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; R3 is selected from hydrogen or methyl.

[0008] As a second aspect of the present invention, a method for preparing an α-diimine ligand compound is provided, comprising:

[0009] Compound A and The reaction yields the first intermediate. The first intermediate reacts with 2,3-butanedione via a Schiff base reaction to give the second intermediate. The second intermediate and compound B Following a Schiff base reaction, an α-diimine ligand compound with the structure shown in formula (I) was obtained.

[0010] As a third aspect of the present invention, an α-diimine nickel catalyst is provided, having a structure as shown in formula (II):

[0011] Formula (II);

[0012] R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; R3 is selected from hydrogen or methyl.

[0013] As a fourth aspect of the present invention, a method for preparing an α-diimine nickel catalyst is provided, wherein the α-diimine nickel catalyst is formed by coordination of an α-diimine ligand compound with a bromide of divalent nickel metal; wherein the bromide of divalent nickel metal is selected from at least one of NiBr2 and (DME)NiBr2, wherein DME is ethylene glycol dimethyl ether.

[0014] As a fifth aspect of the present invention, an application of an α-diimine nickel catalyst in the catalytic polymerization reaction of olefin monomers is provided, comprising: adding a co-catalyst and an olefin monomer to a polymerization solvent, and then adding an α-diimine nickel catalyst to allow the olefin monomer to undergo a polymerization reaction.

[0015] In this invention, a para-methoxy structure is introduced into the α-diimine ligand compound and the α-diimine nickel catalyst. Utilizing the synergistic effect of the electronic and steric hindrance effects of the methoxy structure, the α-diimine nickel catalyst exhibits excellent activity and thermal stability. Furthermore, the weak coordination between the oxygen atom in the methoxy group and the nickel metal center also improves the catalytic performance for olefin polymerization to some extent. Attached Figure Description

[0016] Figure 1a This is the 1H NMR spectrum of α-diimine ligand compound I1 in Example 1 of this invention (… 1 H NMR spectrum;

[0017] Figure 1b This is the carbon NMR spectrum of α-diimine ligand compound I1 in Example 1 of this invention (13 C NMR spectrum;

[0018] Figure 2a It is the α-diimine ligand compound I2 in Example 2 of this invention. 1 H NMR spectrum;

[0019] Figure 2b It is the α-diimine ligand compound I2 in Example 2 of this invention. 13 C NMR spectrum;

[0020] Figure 3a It is the α-diimine ligand compound I3 in Example 3 of this invention. 1 H NMR spectrum;

[0021] Figure 3b It is the α-diimine ligand compound I3 in Example 3 of this invention. 13 C NMR spectrum;

[0022] Figure 4a It is the α-diimine ligand compound I4 in Example 4 of this invention. 1 H NMR spectrum;

[0023] Figure 4b It is the α-diimine ligand compound I4 in Example 4 of this invention. 13 C NMR spectrum;

[0024] Figure 5a It is the α-diimine ligand compound I5 in Example 5 of this invention. 1 H NMR spectrum;

[0025] Figure 5b It is the α-diimine ligand compound I5 in Example 5 of this invention. 13 C NMR spectrum;

[0026] Figure 6a It is the α-diimine ligand compound I6 in Example 6 of this invention. 1 H NMR spectrum;

[0027] Figure 6b It is the α-diimine ligand compound I6 in Example 6 of this invention. 13 C NMR spectrum;

[0028] Figure 7a It is the α-diimine ligand compound I7 in Example 7 of this invention. 1 H NMR spectrum;

[0029] Figure 7b It is the α-diimine ligand compound I7 in Example 7 of this invention. 13 C NMR spectrum;

[0030] Figure 8a It is the α-diimine ligand compound I8 in Example 8 of this invention. 1 H NMR spectrum;

[0031] Figure 8b It is the α-diimine ligand compound I8 in Example 8 of this invention. 13 C NMR spectrum;

[0032] Figure 9a It is the α-diimine ligand compound I9 in Example 9 of this invention. 1 H NMR spectrum;

[0033] Figure 9b It is the α-diimine ligand compound I9 in Example 9 of this invention. 13 C NMR spectrum;

[0034] Figure 10 These are mass spectra of the α-diimine ligand compounds in Examples 1-4 of the present invention, wherein (a) is α-diimine ligand compound I1, (b) is α-diimine ligand compound I2, (c) is α-diimine ligand compound I3, and (d) is α-diimine ligand compound I4;

[0035] Figure 11 These are mass spectra of the α-diimine ligand compounds in Examples 5-8 of the present invention, wherein (a) is α-diimine ligand compound I5, (b) is α-diimine ligand compound I6, (c) is α-diimine ligand compound I7, and (d) is α-diimine ligand compound I8;

[0036] Figure 12 The images show the mass spectra of the α-diimine ligand compounds and α-diimine nickel catalysts of the present invention, wherein (a) is the α-diimine ligand compound I9 in Example 9, (b) is the α-diimine nickel catalyst II1 in Example 10, (c) is the α-diimine nickel catalyst II2 in Example 11, and (d) is the α-diimine nickel catalyst II3 in Example 12;

[0037] Figure 13 The mass spectra of the α-diimine nickel catalysts in Examples 13-18 of this invention are shown below, where (a) is α-diimine nickel catalyst II4, (b) is α-diimine nickel catalyst II5, (c) is α-diimine nickel catalyst II6, (d) is α-diimine nickel catalyst II7, (e) is α-diimine nickel catalyst II8, and (f) is α-diimine nickel catalyst II9.

[0038] Figure 14The image shows the X-ray diffraction single-crystal structure of the α-diimine nickel catalyst of the present invention, wherein (a) is the α-diimine nickel catalyst II4 in Example 13 and (b) is the α-diimine nickel catalyst II5 in Example 14.

[0039] Figure 15 The diagram shows the elastic recovery properties of different polyethylene materials prepared using different catalysts in Application Example 3 of the present invention, where (a) is catalyst Ni1, (b) is catalyst Ni2, (c) is catalyst Ni3, (d) is catalyst Ni4, (e) is catalyst Ni5, (f) is catalyst Ni6, (g) is catalyst Ni7, (h) is catalyst Ni8, and (i) is catalyst Ni9.

[0040] Figure 16 The elastic recovery performance diagram of the polyethylene material in Application Example 1 is shown for comparison. Detailed Implementation

[0041] Given the current limitations of α-diimine nickel catalysts, such as reduced activity, unfavorable conditions for preparing polyolefin materials with higher branching degrees or elastic properties, and limited tolerance to polar monomers, this invention proposes an α-diimine ligand compound containing a para-methoxy group, an α-diimine nickel catalyst, its preparation method, and its applications. The methoxy group (-OCH3), as a substituent with both electron-donating and localized hindrance effects, can be introduced into the α-diimine nickel catalyst to improve the balance of chain transfer and chain walk processes during olefin polymerization by adjusting the electronic environment of the nickel metal center. This allows for effective control of the polymer's branching structure, molecular weight, and molecular weight distribution index, while simultaneously enabling the homopolymer-prepared polyolefin materials to possess elastic properties and good elastic recovery performance.

[0042] As a first aspect of the present invention, an α-diimine ligand compound is provided having a structure as shown in formula (I):

[0043] Formula (I);

[0044] R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; R3 is selected from hydrogen or methyl.

[0045] In embodiments of the present invention, a methoxy (-OCH3) substituent with electron-donating and steric hindrance effects is introduced into the α-diimine ligand compound, laying the foundation for the electronic effect and steric hindrance regulation of the subsequent α-diimine nickel catalyst.

[0046] According to embodiments of the present invention, the α-diimine ligand compound has a structure as shown in any one of formulas (I1) to (I9):

[0047] Formula (I1) Equation (I2), Equation (I3)

[0048] Equation (I4) Formula (I5), Equation (I6)

[0049] Formula (I7) Formula (I8) Equation (I9).

[0050] In some embodiments, the α-diimine ligand compounds of the present invention preferably have a structure as shown in any one of formulas (I4) to (I6):

[0051] Equation (I4) Formula (I5), Equation (I6).

[0052] As a second aspect of the present invention, a method for preparing an α-diimine ligand compound is also provided, comprising:

[0053] Compound A and The reaction yields the first intermediate. The first intermediate reacts with 2,3-butanedione via a Schiff base reaction to give the second intermediate. The second intermediate and compound B The Schiff base reaction yields an α-diimine ligand compound having the structure shown in formula (I), wherein R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; and R3 is selected from hydrogen or methyl.

[0054] According to an embodiment of the present invention, compound A compound L With compound M The reaction was obtained.

[0055] Specifically, the reaction route for synthesizing compound A is shown in equation (1) below.

[0056] Equation (1).

[0057] Specifically, the method for preparing compound A is as follows: Under anhydrous and oxygen-free conditions, 100 mmol of compound M is slowly added dropwise at -30 °C to 50 mL of compound L (i.e., 4-methoxyphenyl magnesium bromide) diluted in tetrahydrofuran (THF). After the addition is complete, the mixture is slowly brought to room temperature and stirred for 6 h. After the reaction is complete, a saturated ammonium chloride aqueous solution is added to quench the reaction, and the mixture is extracted with ethyl acetate. The resulting organic phase is dried, concentrated under reduced pressure, and then petroleum ether is added. Recrystallization yields compound A.

[0058] According to an embodiment of the present invention, the reaction route for synthesizing the first intermediate is shown in equation (2) below.

[0059] Equation (2).

[0060] Specifically, the method for synthesizing the first intermediate is as follows: 50 mmol of compound A is mixed with 55 mmol of 2,4-dimethylaniline and heated to 120 °C. Then, a solution of zinc chloride (ZnCl2) in hydrochloric acid (HCl) is added, and the temperature is adjusted to 160 °C, with the reaction continuing for 4 h. After the reaction is complete and cooled to room temperature, the mixture is extracted with dichloromethane (DCM) and water (H2O). The resulting organic phase is dried, concentrated under reduced pressure, and then methanol (CH3OH or MeOH) is added. Recrystallization yields the first intermediate.

[0061] According to an embodiment of the present invention, the reaction route for synthesizing the second intermediate is shown in equation (3) below.

[0062] Equation (3).

[0063] Specifically, the method for synthesizing the second intermediate is as follows: 25 mmol of the first intermediate, 50 mL of methanol (MeOH), and 100 mmol of 2,3-butanedione are mixed and heated at 90 °C for 8 h, with 0.1 mL of formic acid (HCOOH) added as a catalyst. After the reaction is complete, the methanol solvent is evaporated to dryness to obtain the second intermediate.

[0064] According to an embodiment of the present invention, the reaction route for synthesizing an α-diimine ligand compound having the structure shown in formula (I) from the second intermediate and compound B is shown in formula (4).

[0065] Equation (4).

[0066] Specifically, the method for synthesizing the α-diimine ligand compound having the structure shown in formula (I) is as follows: 10 mmol of the second intermediate, 10 mmol of compound B, 0.2 mmol of p-toluenesulfonic acid monohydrate (PTSA), and 100 mL of toluene (Tol) are added to a 250 mL round-bottom flask. The resulting mixture is refluxed at 150 °C for 24 h. After cooling to room temperature, the solvent is evaporated, and the α-diimine ligand compound having the structure shown in formula (I) is obtained by column chromatography.

[0067] It should be noted that the present invention does not impose any particular restrictions on the preparation method of the α-diimine ligand compound having the structure shown in formula (I). Conventional preparation methods known to those skilled in the art are acceptable. Those skilled in the art can select and adjust the method according to actual production conditions, product requirements and usage requirements.

[0068] As a third aspect of the present invention, an α-diimine nickel catalyst is provided, having a structure as shown in formula (II):

[0069] Formula (II);

[0070] R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; R3 is selected from hydrogen or methyl.

[0071] In embodiments of the present invention, a methoxy structure is introduced into the α-diimine nickel catalyst. By utilizing the synergistic effect of the electronic and steric effects of the methoxy (-OCH3) structure, the α-diimine nickel catalyst exhibits good activity and thermal stability, as well as good tolerance to polar monomers.

[0072] According to embodiments of the present invention, the α-diimine nickel catalyst has a structure as shown in any one of formulas (II1) to (II9):

[0073] Formula (Ⅱ1) Formula (Ⅱ2) Formula (Ⅱ3) Formula (Ⅱ4) Formula (Ⅱ5), Formula (Ⅱ6) Formula (Ⅱ7) Formula (Ⅱ8) Formula (Ⅱ9).

[0074] As a fourth aspect of the present invention, a method for preparing an α-diimine nickel catalyst having the structure shown in Formula (II) is also provided, wherein the α-diimine nickel catalyst is formed by coordination of the above-mentioned α-diimine ligand compound with a bromide of divalent nickel metal, wherein the bromide of divalent nickel metal includes at least one of NiBr2 and (DME)NiBr2, wherein DME is ethylene glycol dimethyl ether.

[0075] Specifically, the method for preparing an α-diimine nickel catalyst having the structure shown in formula (II) includes: dissolving an α-diimine ligand compound having the structure shown in formula (I) and a bromide of divalent nickel in a 1:1 molar ratio in an organic solvent, stirring for 6 h, concentrating the reaction under vacuum, adding a saturated alkane for recrystallization for 30 min, and filtering to obtain an α-diimine nickel catalyst having the structure shown in formula (II). The organic solvent is selected from at least one of dichloromethane (DCM), tetrahydrofuran (THF), ethyl acetate, or toluene (Tol), and the saturated alkane used in the recrystallization process is selected from at least one of n-pentane, n-hexane, or n-heptane.

[0076] According to embodiments of the present invention, the preparation of the α-diimine nickel catalyst having the structure shown in formula (II) is preferably carried out in a protective atmosphere, wherein the protective atmosphere may be nitrogen or other inert gas; the reaction conditions are preferably carried out under anhydrous and oxygen-free or almost anhydrous and oxygen-free conditions.

[0077] As a fifth aspect of the present invention, an application of an α-diimine nickel catalyst in the catalytic polymerization reaction of olefin monomers is provided, comprising: adding a co-catalyst and an olefin monomer to a polymerization solvent, and then adding an α-diimine nickel catalyst to allow the olefin monomer to undergo a polymerization reaction.

[0078] In this invention, the synergistic effect of the electronic and steric effects of the methoxy structure enables the α-diimine nickel catalyst to exhibit good activity and thermal stability, ensuring the smooth progress of the polymerization reaction. Simultaneously, the oxygen atom in the methoxy group of the α-diimine nickel catalyst exhibits a relatively weak coordination interaction with the nickel metal center, which significantly affects the catalyst's performance in olefin polymerization, such as giving the polyolefin material formed by homopolymerization resilience.

[0079] According to an embodiment of the present invention, the olefin monomer is C2-C. 11 α-olefins selected from straight-chain C2-C 11 α-olefins or branched C2-C 11 α-olefins, the C2-C 11 The α-olefin is selected from at least one of ethylene, propylene, butene, pentene, hexene, hepten, octene, nonene, decene, undecene, and 6-chloro-1-hexene. Alternatively, the olefin monomer is C2-C. 11The polymerization reaction involves an α-olefin and a polar monomer, wherein the polar monomer is selected from at least one of methacrylic acid, methyl methacrylate, ethyl methacrylate, 10-undecenol, and 10-undecenic acid. Therefore, the polymerization reaction of the olefin monomer includes C2~C2. 11 The homopolymerization of α-olefins, or C2~C 11 The copolymerization reaction of α-olefins with polar monomers.

[0080] According to embodiments of the present invention, the polymerization solvent is selected from at least one of toluene, benzene, n-hexane, and n-heptane. The co-catalyst is selected from at least one of alkylaluminum and alkylaluminum chloride, wherein the alkylaluminum is selected from at least one of trimethylaluminum, triethylaluminum, tri-n-butylaluminum, and triisobutylaluminum, and the alkylaluminum chloride is selected from at least one of diethylaluminum chloride and dichloroethylaluminum.

[0081] According to an embodiment of the present invention, the temperature of the polymerization reaction is 30℃-80℃, for example, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, etc.; the pressure of the polymerization reaction is 8-10 atm, for example, 8 atm, 9 atm, 10 atm, etc.

[0082] According to embodiments of the present invention, the polyolefin material formed by homopolymerization has elastic recovery properties, wherein the elastic recovery rate is greater than 80%. For example, the polyethylene elastomer material formed by homopolymerization has an elastic recovery rate greater than 80%.

[0083] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a comprehensive explanation of the embodiments of the invention for ease of explanation. 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. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0084] It should be noted that the following examples illustrate the specific content of the present invention, and the data given include the synthesis of α-diimine ligand compounds, the synthesis of α-diimine nickel catalysts, and the homopolymerization or copolymerization methods of ethylene. The synthesis of α-diimine ligand compounds and the olefin polymerization process are carried out under anhydrous and oxygen-free conditions; all sensitive substances are stored in a glove box; all solvents are strictly dried to remove water; and ethylene gas is purified by passing it through a dehydration and deoxygenation column. Unless otherwise specified, all raw materials can be purchased and used directly. The methods used in the following examples, such as column chromatography, are methods well-known in the art and can be described in textbooks or relevant literature, and will not be elaborated further.

[0085] In this embodiment of the invention, NMR detection was performed using a Bruker 400MHz NMR instrument, elemental analysis and melting point were determined by the Physical and Chemical Center of the University of Science and Technology of China, molecular weight and molecular weight distribution index were determined by high temperature (160℃) and / or room temperature gel permeation chromatography (GPC), high resolution mass spectrometry (HRMS) was performed using a Thermo LTQ Orbitrap XL, single crystal analysis was performed using a Bruker Smart CCD, and cycle recovery performance was determined using a universal testing machine.

[0086] Example 1

[0087] The specific synthetic route of the α-diimine ligand compound I1 is shown in equation (5) below.

[0088] Equation (5).

[0089] To a 250 mL round-bottom flask, add the second intermediate Q1 (10 mmol), 2,4,6-trimethylaniline (10 mmol), p-toluenesulfonic acid monohydrate (PTSA, 0.2 mmol), and 100 mL of toluene (Tol). The resulting mixture was refluxed at 150 °C for 24 h. After cooling to room temperature, the solvent was evaporated, and the mixture was separated by column chromatography to obtain a yellow solid, namely the α-diimine ligand compound I1, with a mass of 2.67 g and a reaction yield of 53.2%.

[0090] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I1 was characterized by C1NMR and mass spectrometry, and the specific characterization results are as follows: Figure 1a , Figure 1b and Figure 10 As shown in (a) of the diagram.

[0091] Figure 1a It is the α-diimine ligand compound I1 in Example 1 of this invention. 1 H NMR spectrum Figure 1b It is the α-diimine ligand compound I1 in Example 1 of this invention. 13 C NMR spectrum, Figure 10 (a) is the mass spectrum of α-diimine ligand compound I1 in Example 1 of this invention.

[0092] 1H NMR (400 MHz, CDCl3) δ 7.20 - 7.07 (m, 3H), 6.98 (t, J = 7.8 Hz, 2H), 6.90 (dd, J = 8.7, 7.4 Hz, 2H), 6.85 (d, J = 1.9 Hz, 1H), 6.78 (d, J =7.3 Hz, 2H), 6.70 (dd, J = 15.0, 8.7 Hz, 2H), 6.52 (d, J = 14.5 Hz, 1H), 5.29(s, 1H), 3.67 (d, J = 13.3 Hz, 3H), 2.19 (s, 3H), 2.15 (d, J = 5.6 Hz, 3H),1.91 (d, J = 1.8 Hz, 3H), 1.90 - 1.86 (m, 6H), 1.84 (d, J = 4.5 Hz, 3H), 1.25 (d, J = 27.5 Hz, 3H).

[0093] 13 C NMR (101 MHz, CDCl3) δ 169.36, 169.33, 167.99, 167.93, 157.96,157.86, 145.95, 145.55, 145.48, 144.14, 143.08, 135.91, 134.78, 132.99,132.92, 132.36, 132.34, 132.18, 130.59, 130.51, 129.63, 129.53, 129.27,129.24, 128.70, 128.58, 128.58, 128.55, 128.53, 128.44, 128.08, 127.77, 127.74, 126.17, 126.02, 124.44, 124.42, 124.37, 124.25, 124.23, 113.79, 113.48, 55.24, 55.18, 51.70, 51.56, 21.10, 21.08, 20.77, 18.00, 17.98, 17.77, 17.68, 17.62, 17.59, 15.84, 15.82, 15.74, 15.62.

[0094] HRMS (m / z): Theoretical calculated value C 35 H 38 N₂O: [M+H] +503.30624, experimentally measured value: 503.30560.

[0095] Example 2

[0096] The specific synthetic route of the α-diimine ligand compound I2 is shown in equation (6) below.

[0097] Equation (6).

[0098] The α-diimine ligand compound I2 was prepared using the same method as in Example 1, except that 2,6-diethylaniline was used instead of 2,4,6-trimethylaniline. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I2 weighed 3.0 g, with a reaction yield of 52.1%.

[0099] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I2 was characterized by C1NMR and mass spectrometry, and the specific characterization results are as follows: Figure 2a , Figure 2b and Figure 10 As shown in (b) of the diagram.

[0100] Figure 2a It is the α-diimine ligand compound I2 in Example 2 of this invention. 1 H NMR spectrum Figure 2b It is the α-diimine ligand compound I2 in Example 2 of this invention. 13 C NMR spectrum, Figure 10 (b) is the mass spectrum of α-diimine ligand compound I2 in Example 2 of the present invention.

[0101] 1H NMR (400 MHz, CDCl3) δ 7.19-7.08 (m, 3H), 7.04-6.97 (m, 4H), 6.95-6.89 (m, 3H), 6.85 (s, 1H), 6.72 (t, J = 8.6 Hz, 2H), 6.53 (d, J = 11.2 Hz,1H), 5.30 (d, J = 2.7 Hz, 1H), 3.68 (d, J = 9.1 Hz, 3H), 2.23 (dqd, J = 11.8,7.8, 3.1 Hz, 4H), 2.15 (d, J = 5.3 Hz, 3H), 1.93 (d, J = 1.4 Hz, 3H), 1.87(d, J = 3.7 Hz, 3H), 1.23-1.16 (m, 3H), 1.10 (q, J = 7.4 Hz, 3H), 1.02 (td, J= 7.5, 3.5 Hz, 3H).

[0102] 13 C NMR (101 MHz, CDCl3) δ 169.33, 169.31, 167.73, 167.64, 158.01,157.87, 147.45, 145.52, 145.46, 144.16, 143.11, 135.93, 134.78, 132.98,132.90, 132.22, 130.59, 130.51, 130.39, 130.36, 130.34, 129.62, 129.52,129.29, 129.26, 128.42, 128.08, 127.80, 127.76, 126.16, 126.07, 126.03, 126.00, 125.92, 124.21, 123.49, 123.46, 113.76, 113.49, 55.25, 55.19, 51.69, 51.54, 24.67, 24.50, 24.47, 24.35, 21.10, 21.09, 17.58, 17.56, 16.33, 15.70, 15.60, 13.93, 13.58, 13.56, 13.15.

[0103] HRMS (m / z): Theoretical calculated value C 36 H 40 N₂O: [M+H] +517.32189, experimentally measured value: 517.32123.

[0104] Example 3

[0105] The specific synthetic route of the α-diimine ligand compound I3 is shown in equation (7) below.

[0106] Equation (7).

[0107] The α-diimine ligand compound I3 was prepared using the same method as in Example 1, except that 2,6-diisopropylaniline was used instead of 2,6-diethylaniline. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I3 weighed 3.0 g, with a reaction yield of 55.2%.

[0108] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I3 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 3a , Figure 3b and Figure 10 As shown in (c) in the figure.

[0109] Figure 3a It is the α-diimine ligand compound I3 in Example 3 of this invention. 1 H NMR spectrum Figure 3b It is the α-diimine ligand compound I3 in Example 3 of this invention. 13 C NMR spectrum, Figure 10 (c) is the mass spectrum of α-diimine ligand compound I3 in Example 3 of this invention.

[0110] 1 H NMR (400 MHz, CDCl3) δ 7.23-7.18 (m, 1H), 7.13-7.04 (m, 3H), 7.03-6.96 (m, 4H), 6.95-6.90 (m, 2H), 6.87 (s, 1H), 6.77-6.72 (m, 2H), 6.53 (d, J= 10.3 Hz, 1H), 5.31 (s, 1H), 3.74-3.67 (m, 3H), 2.60-2.46 (m, 2H), 2.21-2.13(m, 3H), 1.96 (d, J = 3.1 Hz, 3H), 1.89 (t, J = 3.6 Hz, 3H), 1.23 -1.18 (m,9H), 1.12-1.02 (m,9H).

[0111] 13 C NMR (101 MHz, CDCl3) δ 168.27, 166.79, 166.68, 156.93, 156.78,145.09, 144.44, 144.37, 143.08, 142.04, 134.84, 133.94, 133.90, 133.86,133.83, 133.66, 131.89, 131.80, 131.44, 131.13, 129.52, 129.43, 128.54,128.43, 128.21, 128.18, 127.27, 127.00, 126.70, 126.66, 125.06, 124.96, 123.12, 122.67, 121.93, 121.73, 117.56, 112.62, 112.41, 54.17, 50.60, 50.42, 27.44, 27.08, 26.99, 26.88, 22.39, 22.36, 22.11, 22.00, 21.86, 21.83, 21.67, 21.42, 20.02, 16.49, 15.63, 14.65, 14.59.

[0112] HRMS (m / z): Theoretical calculated value C 38 H 44 N₂O: [M+H] + 545.35319, experimentally measured value: 545.35260.

[0113] Example 4

[0114] The specific synthetic route of the α-diimine ligand compound I4 is shown in equation (8) below.

[0115] Equation (8).

[0116] The α-diimine ligand compound I4 was prepared using the same method as in Example 1, except that the second intermediate Q2 was used instead of the second intermediate Q1. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I4 weighed 2.8 g, with a reaction yield of 53.3%.

[0117] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I4 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 4a , Figure 4b and Figure 10 As shown in (d) in the figure.

[0118] Figure 4a It is the α-diimine ligand compound I4 in Example 4 of this invention. 1 H NMR spectrum Figure 4b It is the α-diimine ligand compound I4 in Example 4 of this invention. 13 C NMR spectrum, Figure 10 (d) is the mass spectrum of α-diimine ligand compound I4 in Example 4 of this invention.

[0119] 1 H NMR (400 MHz, CDCl3) δ 7.02-6.96 (m, 4H), 6.93 (d, J = 1.8 Hz, 1H), 6.88 (d, J = 5.2 Hz, 2H), 6.79 (dd, J = 16.9, 8.7 Hz, 4H), 6.62-6.59 (m, 1H),5.32 (s, 1H), 3.79 (s, 3H), 3.75 (s, 3H), 2.29 (s, 3H), 2.24 (s, 3H), 2.00(s, 3H), 1.98 (s, 3H), 1.96 (s, 3H), 1.94 (s, 3H), 1.37 (s, 3H).

[0120] 13 C NMR (101 MHz, CDCl3) δ 168.22, 166.93, 156.86, 156.78, 144.91,144.45, 135.27, 134.17, 132.11, 131.28, 131.09, 129.43, 129.36, 128.11,127.52, 127.46, 126.62, 123.35, 123.32, 123.14, 112.73, 112.40, 54.17, 54.11,49.71, 20.01, 19.68, 16.91, 16.59, 16.51, 14.74, 14.66.

[0121] HRMS (m / z): Theoretical calculated value C 36 H 40 N₂O₂: [M+H] + 533.31680, experimentally measured value: 533.31616.

[0122] Example 5

[0123] The specific synthetic route of the α-diimine ligand compound I5 is shown in equation (9) below.

[0124] Equation (9).

[0125] The α-diimine ligand compound I5 was prepared using the same method as in Example 1, except that second intermediate Q2 was used instead of second intermediate Q1 and 2,6-diethylaniline was used instead of 2,4,6-trimethylaniline. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I5 weighed 2.8 g, with a reaction yield of 50.7%.

[0126] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I5 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 5a , Figure 5b and Figure 11 As shown in (a) of the diagram.

[0127] Figure 5a It is the α-diimine ligand compound I5 in Example 5 of this invention. 1 H NMR spectrum Figure 5b It is the α-diimine ligand compound I5 in Example 5 of this invention. 13 C NMR spectrum, Figure 11 (a) is the mass spectrum of α-diimine ligand compound I5 in Example 5 of this invention.

[0128] 1 H NMR (400 MHz, CDCl3) δ 7.12 -7.06 (m, 2H), 7.02 (d, J = 7.5 Hz,1H), 6.99 (s, 1H), 6.98 (d, J = 3.2 Hz, 2H), 6.96 (s, 1H), 6.93 (s, 1H),6.82-6.76 (m, 4H), 6.60 (s, 1H), 5.31 (s, 1H), 3.77 (d, J = 11.0 Hz, 6H),2.37-2.26 (m, 4H), 2.24 (s, 3H), 2.01 (s, 3H), 1.95 (s, 3H), 1.36 (s, 3H), 1.19 (t, J = 7.5 Hz, 3H), 1.10 (t, J = 7.5 Hz, 3H).

[0129] 13C NMR (101 MHz, CDCl3) δ 168.20, 166.67, 156.92, 156.80, 146.41,144.41, 135.29, 134.17, 132.10, 131.12, 129.43, 129.35, 129.33, 129.30,128.13, 126.65, 124.97, 124.86, 123.10, 122.43, 112.70, 112.40, 54.17, 54.12,49.69, 23.60, 23.43, 20.01, 16.48, 15.25, 14.62, 12.85, 12.50.

[0130] HRMS (m / z): Theoretical calculated value C 37 H 42 N₂O₂: [M+H] + 547.33245, experimentally measured value: 547.33179.

[0131] Example 6

[0132] The specific synthetic route of the α-diimine ligand compound I6 is shown in equation (10).

[0133] Equation (10).

[0134] The α-diimine ligand compound I6 was prepared using the same method as in Example 1, except that second intermediate Q2 was used instead of second intermediate Q1 and 2,6-diisopropylaniline was used instead of 2,4,6-trimethylaniline. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I6 weighed 3.2 g, with a reaction yield of 55.2%.

[0135] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I6 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 6a , Figure 6b and Figure 11 As shown in (b) of the diagram.

[0136] Figure 6a It is the α-diimine ligand compound I6 in Example 6 of this invention. 1 H NMR spectrum Figure 6b It is the α-diimine ligand compound I6 in Example 6 of this invention. 13 C NMR spectrum, Figure 11(b) is the mass spectrum of α-diimine ligand compound I6 in Example 6 of this invention.

[0137] 1 H NMR (400 MHz, CDCl3) δ 7.10-7.05 (m, 2H), 7.01 (d, J = 7.5 Hz, 1H), 6.90 (dd, J = 8.4, 4.2 Hz, 4H), 6.86 (s, 1H), 6.75-6.69 (m, 4H), 6.53 (s,1H), 5.24 (s, 1H), 3.71 (s, 3H), 3.68 (s, 3H), 2.58-2.50 (m, 2H), 2.17 (s,3H), 1.96 (s, 3H), 1.88 (s, 3H), 1.29 (s, 3H), 1.19 (d, J = 7.5 Hz, 3H), 1.13-1.04 (m, 9H).

[0138] 13 C NMR (101 MHz, CDCl3) δ 169.33, 167.89, 158.01, 157.87, 146.19,145.45, 136.37, 135.22, 135.03, 134.97, 133.16, 132.21, 130.51, 130.42,129.21, 127.70, 124.17, 123.77, 123.03, 123.00, 113.72, 113.48, 55.25, 55.21,50.73, 28.53, 28.17, 23.46, 23.15, 22.94, 22.72, 21.08, 17.55, 16.72, 15.73.

[0139] HRMS (m / z): Theoretical calculated value C 39 H 46 N₂O₂: [M+H] + 575.36375, experimentally measured value: 575.36316.

[0140] Example 7

[0141] The specific synthetic route of the α-diimine ligand compound I7 is shown in equation (11) below.

[0142] Equation (11).

[0143] The α-diimine ligand compound I7 was prepared using the same method as in Example 1, except that the second intermediate Q3 was used instead of the second intermediate Q1. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I7 weighed 2.9 g, with a reaction yield of 51.0%.

[0144] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I7 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 7a , Figure 7b and Figure 11 As shown in (c) in the figure.

[0145] Figure 7a It is the α-diimine ligand compound I7 in Example 7 of this invention. 1 H NMR spectrum Figure 7b It is the α-diimine ligand compound I7 in Example 7 of this invention. 13 C NMR spectrum, Figure 11 (c) is the mass spectrum of α-diimine ligand compound I7 in Example 7 of this invention.

[0146] 1 H NMR (400 MHz, CDCl3) δ 7.27-7.21 (m, 2H), 7.03-6.95 (m, 4H), 6.91(s, 1H), 6.86 (d, J = 7.0 Hz, 2H), 6.81 (d, J = 8.7 Hz, 1H), 6.76 (d, J = 8.7Hz, 1H), 6.63 (d, J = 5.2 Hz, 1H), 5.32 (s, 1H), 3.76 (d, J = 14.8 Hz, 3H), 2.27 -2.22 (m, 6H), 2.01-1.92 (m, 12H), 1.32 (d, J = 20.9 Hz, 6H), 1.26 (s, 6H).

[0147] 13C NMR (101 MHz, CDCl3) δ 169.38, 169.35, 168.01, 157.92, 157.84,148.91, 148.69, 146.03, 145.56, 145.45, 141.04, 139.87, 136.05, 135.06,133.35, 133.05, 132.35, 132.32, 132.15, 132.11, 130.58, 130.51, 129.27,129.18, 129.14, 129.07, 128.58, 128.53, 128.48, 127.72, 127.61, 125.23, 124.94, 124.46, 124.43, 124.38, 124.32, 124.16, 113.77, 113.45, 55.23, 55.18, 51.18, 51.08, 34.37, 34.34, 31.42, 31.39, 26.95, 21.08, 20.74, 18.12, 17.97, 17.65, 17.58, 17.51, 15.85, 15.80, 15.66, 15.39.

[0148] HRMS (m / z): Theoretical calculated value C 39 H 46 N₂O: [M+H] + 559.36884, experimentally measured value: 559.36829.

[0149] Example 8

[0150] The specific synthetic route of the α-diimine ligand compound I8 is shown in equation (12) below:

[0151] Equation (12).

[0152] The α-diimine ligand compound I8 was prepared using the same method as in Example 1, except that second intermediate Q3 was used instead of second intermediate Q1 and 2,6-diethylaniline was used instead of 2,4,6-trimethylaniline. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I8 weighed 3.2 g, with a reaction yield of 56.4%.

[0153] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I8 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 8a , Figure 8b and Figure 11 As shown in (d) in the figure.

[0154] Figure 8a It is the α-diimine ligand compound I8 in Example 8 of this invention. 1 H NMR spectrum Figure 8b It is the α-diimine ligand compound I8 in Example 8 of this invention. 13 C NMR spectrum Figure 11 (d) is the mass spectrum of α-diimine ligand compound I8 in Example 8 of this invention.

[0155] 1 H NMR (400 MHz, CDCl3) δ 7.28-7.24 (m, 2H), 7.12-7.06 (m, 2H), 7.04-6.97 (m, 5H), 6.92 (d, J = 4.4 Hz, 1H), 6.79 (dd, J = 12.1, 8.7 Hz, 2H), 6.65(s, 1H), 5.32 (d, J = 5.4 Hz, 1H), 3.76 (d, J = 10.4 Hz, 3H), 2.40-2.26 (m,4H), 2.24 (s, 3H), 2.02 (d, J = 11.9 Hz, 3H), 1.94 (d, J = 8.5 Hz, 3H), 1.28 (d, J = 9.4 Hz, 9H), 1.23-1.16 (m, 3H), 1.12-1.08 (m, 3H).

[0156] 13C NMR (101 MHz, CDCl3) δ 169.45, 169.33, 167.81, 167.75, 157.96,157.84, 149.00, 148.71, 147.49, 147.46, 145.50, 145.39, 141.05, 139.83,136.04, 135.05, 133.27, 133.04, 132.19, 132.14, 130.58, 130.48, 130.36,129.31, 129.19, 129.15, 129.05, 127.74, 127.61, 126.02, 125.91, 125.83, 125.18, 124.94, 124.14, 124.09, 123.47, 113.74, 113.45, 55.24, 55.19, 51.09, 51.05, 34.37, 31.42, 31.39, 26.95, 24.64, 24.47, 24.29, 21.08, 17.54, 17.48, 16.42, 16.31, 15.63, 15.29, 14.08, 13.92, 13.55, 13.51.

[0157] HRMS (m / z): Theoretical calculated value C 40 H 48 N₂O: [M+H] + 573.38449, experimentally measured value: 573.38391.

[0158] Example 9

[0159] The specific synthetic route of α-diimine ligand compound I9 is ​​shown in (13).

[0160] (13).

[0161] The α-diimine ligand compound I9 was prepared using the same method as in Example 1, except that intermediate Q3 was used instead of intermediate Q1 and 2,6-diisopropylaniline was used instead of 2,4,6-trimethylaniline. All other conditions remained the same and will not be repeated here. The obtained α-diimine ligand compound I9 weighed 3.3 g, with a reaction yield of 54.2%.

[0162] use 1 H NMR spectrum, 13 The structure of the α-diimine ligand compound I9 was characterized by C10 NMR and mass spectrometry, and the specific characterization results are as follows: Figure 9a , Figure 9b and Figure 12 As shown in (a) of the diagram.

[0163] Figure 9a It is the α-diimine ligand compound I9 in Example 9 of this invention. 1 H NMR spectrum Figure 9b It is the α-diimine ligand compound I9 in Example 9 of this invention. 13 C NMR spectrum Figure 12 (a) is the mass spectrum of α-diimine ligand compound I9 in Example 9 of the present invention.

[0164] 1 H NMR (400 MHz, CDCl3) δ 7.18 (dd, J = 8.1, 5.8 Hz, 2H), 7.10-7.03(m, 2H), 7.00 (d, J = 7.1 Hz, 1H), 6.91 (d, J = 8.6 Hz, 4H), 6.84 (d, J = 4.8Hz, 1H), 6.71 (t, J = 9.3 Hz, 2H), 6.58 (s, 1H), 5.25 (d, J = 6.1 Hz, 1H), 3.68 (d, J = 7.7 Hz, 3H), 2.65-2.48 (m, 2H), 2.16 (s, 3H), 1.96 (d, J = 14.1Hz, 3H), 1.87 (d, J = 9.0 Hz, 3H), 1.21 (d, J = 6.4 Hz, 9H), 1.16 (d, J = 9.8Hz, 6H), 1.07-1.01 (m, 6H).

[0165] 13C NMR (101 MHz, CDCl3) δ 168.40, 168.27, 166.94, 166.83, 156.93,156.79, 147.98, 147.66, 145.18, 145.15, 144.50, 144.39, 140.01, 138.75,135.01, 134.05, 133.98, 133.93, 133.89, 132.18, 131.95, 131.10, 131.04,129.54, 129.40, 128.30, 128.14, 128.11, 128.00, 126.67, 126.54, 124.09, 123.89, 123.04, 122.97, 122.68, 122.00, 121.96, 121.93, 112.64, 112.40, 54.17, 54.14, 49.98, 33.31, 30.36, 27.46, 27.42, 27.10, 26.90, 22.57, 22.43, 22.40, 22.10, 21.90, 21.87, 21.65, 21.59, 21.42, 20.03, 16.49, 16.42, 15.81, 15.63, 14.59, 14.20.

[0166] HRMS (m / z): Theoretical calculated value C 42 H 52 N₂O: [M+H] + 601.41579, experimentally measured value: 601.41504.

[0167] Example 10: Synthesis of α-diimine nickel catalyst II1

[0168] In a glove box, the α-diimine ligand compound I1 (2.0 mmol) prepared in Example 1 was added to a mixed solution of DCM and (DME)NiBr2 (0.62 g, 2.0 mmol) in 20 mL. The mixture was stirred at room temperature for 12 h. The solution was dried under vacuum, and 30 mL of n-hexane was added and stirred for 15 min. The dark red solid obtained by filtration was α-diimine nickel catalyst II1 (i.e. catalyst Ni1), with a mass of 1.3 g and a reaction yield of 90.2%.

[0169] The structure of the α-diimine nickel catalyst II1 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry (MALDI-TOF). The specific characterization results are as follows: Figure 12 As shown in (b) of the diagram.

[0170] Figure 12 (b) is the mass spectrum of the α-diimine nickel catalyst II1 in Example 10 of the present invention.

[0171] Elemental analysis results: Analytical calculation value C 35 H 38 Br2N2NiO: C, 58.29; H, 5.31; N, 3.88. Experimentally measured values: C, 58.83; H, 5.62; N, 3.49.

[0172] Mass spectrometry results: MALDI-TOF: m / z 638.9424 [M-Br] + 641.0082 [M-Br + 2H] + .

[0173] Example 11: Synthesis of α-diimine nickel catalyst II2

[0174] α-Diimine nickel catalyst II2 was prepared using the same method as in Example 10, except that α-diimine ligand compound I2 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II2 (i.e., catalyst Ni2) was 1.3 g, representing a yield of 88.9%.

[0175] The structure of α-diimine nickel catalyst II2 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. The specific characterization results are as follows: Figure 12 As shown in (c) in the figure.

[0176] Figure 12 (c) is the mass spectrum of α-diimine nickel catalyst II2 in Example 11 of the present invention.

[0177] Elemental analysis results: Analytical calculation value C 36 H 40 Br2N2NiO: C, 58.81; H, 5.48; N, 3.81. Experimentally measured values: C, 58.88; H, 5.66; N, 3.51.

[0178] Mass spectrometry results: MALDI-TOF: m / z 652.9942 [M-Br] + 655.0595 [M-Br + 2H] + .

[0179] Example 12: Synthesis of α-diimine nickel catalyst II3

[0180] α-Diimine nickel catalyst II3 was prepared using the same method as in Example 10, except that α-diimine ligand compound I3 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II3 (i.e., catalyst Ni3) was 1.3 g, representing a yield of 87.9%.

[0181] The structure of α-diimine nickel catalyst II3 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. The specific characterization results are as follows: Figure 12 As shown in (d) in the figure.

[0182] Figure 12(d) is the mass spectrum of α-diimine nickel catalyst II3 in Example 12 of the present invention.

[0183] Elemental analysis results: Analytical calculation value C 38 H 44 Br2N2NiO: C, 59.80; H, 5.81; N, 3.67. Experimentally measured values: C, 59.65; H, 5.78; N, 3.77.

[0184] Mass spectrometry results: MALDI-TOF: m / z 680.9977 [M-Br] + 683.0690 [M-Br+2H] + .

[0185] Example 13: Synthesis of α-diimine nickel catalyst II4

[0186] α-Diimine nickel catalyst II4 was prepared using the same method as in Example 10, except that α-diimine ligand compound I4 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II4 (i.e., catalyst Ni4) was 1.3 g, representing a yield of 86.7%.

[0187] The structure of α-diimine nickel catalyst II4 was characterized by elemental analysis, matrix-assisted laser desorption / ionization time-of-flight mass spectrometry, and single-crystal X-ray diffraction. Specific characterization results are as follows: Figure 13 (a) Figure 14 As shown in (a) and Table 1.

[0188] Figure 13 (a) is the mass spectrum of α-diimine nickel catalyst II4 in Example 13 of this invention. Figure 14(a) is the X-ray diffraction single crystal structure diagram of α-diimine nickel catalyst II4 in Example 13 of the present invention, and Table 1 is the crystal structure data table of α-diimine nickel catalyst II4 in Example 13 of the present invention.

[0189] Elemental analysis results: Analytical calculation value C 36 H 40 Br2N2NiO2: C, 57.56; H, 5.37; N, 3.73. Experimentally measured values: C, 57.46; H, 5.48; N, 3.88.

[0190] Mass spectrometry results: MALDI-TOF: m / z 669.0500 [M-Br] + 671.1208 [M-Br + 2H] + .

[0191] Table 1

[0192]

[0193] As shown in Table 1, the α-diimine nickel catalyst II4 has a single-crystal structure. In this single-crystal structure, the α-diimine nickel catalyst II4 coordinates with three water molecules. Therefore, the empirical formula in Table 1 is C. 36 H 46 Br2N2NiO5.

[0194] Example 14: Synthesis of α-diimine nickel catalyst II5

[0195] α-Diimine nickel catalyst II5 was prepared using the same method as in Example 10, except that α-diimine ligand compound I5 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II5 (i.e., catalyst Ni5) was 1.4 g, representing a yield of 91.1%.

[0196] The structure of α-diimine nickel catalyst II5 was characterized by elemental analysis, matrix-assisted laser desorption / ionization time-of-flight mass spectrometry, and single-crystal X-ray diffraction. Specific characterization results are as follows: Figure 13 (b) Figure 14 As shown in (b) and Table 2.

[0197] Figure 13 (b) is the mass spectrum of α-diimine nickel catalyst II5 in Example 14 of this invention. Figure 14 (b) is the X-ray diffraction single crystal structure diagram of α-diimine nickel catalyst II5 in Example 14 of the present invention, and Table 2 is the crystal structure data table of α-diimine nickel catalyst II5 in Example 14 of the present invention.

[0198] Elemental analysis results: Analytical calculation value C 37 H 42 Br2N2NiO2: C, 58.07; H, 5.53; N, 3.66. Experimentally measured values: C, 58.54; H, 5.42; N, 3.49.

[0199] Mass spectrometry results: MALDI-TOF: m / z 682.9405 [M-Br] + 685.0376 [M-Br + 2H] + .

[0200] Table 2

[0201]

[0202] As shown in Table 2, the α-diimine nickel catalyst II5 has a single-crystal structure. In this single-crystal structure, the α-diimine nickel catalyst II5 is not coordinated with water molecules. Therefore, the empirical formula in Table 2 is C. 37 H 42 Br2N2NiO2.

[0203] Example 15: Synthesis of α-diimine nickel catalyst II6

[0204] α-Diimine nickel catalyst II6 was prepared using the same method as in Example 10, except that α-diimine ligand compound I6 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II6 (i.e., catalyst Ni6) was 1.4 g, representing a yield of 89.4%.

[0205] The structure of α-diimine nickel catalyst II6 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. The specific characterization results are as follows: Figure 13 As shown in (c) in the figure.

[0206] Figure 13 (c) is the mass spectrum of α-diimine nickel catalyst II6 in Example 15 of the present invention.

[0207] Elemental analysis results: Analytical calculation value C 39 H 46 Br2N2NiO2: C, 59.05; H, 5.84; N, 3.53. Experimentally measured values: C, 59.33; H, 5.66; N, 3.46.

[0208] Mass spectrometry results: MALDI-TOF: m / z 710.9734 [M-Br] + 713.0728 [M-Br + 2H] + .

[0209] Example 16: Synthesis of α-diimine nickel catalyst II7

[0210] α-Diimine nickel catalyst II7 was prepared using the same method as in Example 10, except that α-diimine ligand compound I7 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II7 (i.e., catalyst Ni7) was 1.4 g, representing a yield of 88.4%.

[0211] The structure of α-diimine nickel catalyst II7 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. The specific characterization results are as follows: Figure 13 As shown in (d) in the figure.

[0212] Figure 13 (d) is the mass spectrum of α-diimine nickel catalyst II7 in Example 16 of this invention.

[0213] Elemental analysis results: Analytical calculation value C 39 H 46 Br2N2NiO: C, 60.26; H, 5.97; N, 3.60. Experimentally measured values: C, 60.46; H, 5.79; N, 3.59.

[0214] Mass spectrometry results: MALDI-TOF: m / z 694.9453 [M-Br] + 697.0541 [M-Br + 2H] + .

[0215] Example 17: Synthesis of α-diimine nickel catalyst II8

[0216] α-Diimine nickel catalyst II8 was prepared using the same method as in Example 10, except that α-diimine ligand compound I8 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II8 (i.e., catalyst Ni8) was 1.4 g, representing a yield of 87.7%.

[0217] The structure of α-diimine nickel catalyst II8 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. The specific characterization results are as follows: Figure 13 As shown in (e) in the diagram.

[0218] Figure 13 (e) is the mass spectrum of the α-diimine nickel catalyst II8 in Example 17 of this invention.

[0219] Elemental analysis results: Analytical calculation value C 40 H 48 Br2N2NiO: C, 60.71; H, 6.11; N, 3.54. Experimentally measured values: C, 60.82; H, 6.02; N, 3.68.

[0220] Mass spectrometry results: MALDI-TOF: m / z 709.0465 [M-Br] + 711.0884 [M-Br + 2H] + .

[0221] Example 18: Synthesis of α-diimine nickel catalyst II9

[0222] α-Diimine nickel catalyst II9 was prepared using the same method as in Example 10, except that α-diimine ligand compound I9 was used instead of α-diimine ligand compound I1. All other conditions remained the same and will not be repeated here. The yield of α-diimine nickel catalyst II9 (i.e., catalyst Ni9) was 1.5 g, representing a yield of 89.8%.

[0223] The structure of α-diimine nickel catalyst II9 was characterized by elemental analysis and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry. The specific characterization results are as follows: Figure 13 As shown in (f) in the figure.

[0224] Figure 13 (f) is the mass spectrum of α-diimine nickel catalyst II9 in Example 18 of the present invention.

[0225] Elemental analysis results: Analytical calculation value C 42 H 52 Br2N2NiO: C, 61.57; H, 6.40; N, 3.42. Experimentally measured values: C, 61.55; H, 6.37; N, 3.49.

[0226] Mass spectrometry results: MALDI-TOF: m / z 736.9833 [M-Br] + 739.0694 [M-Br + 2H] + .

[0227] Comparative Example 1

[0228] α-Diimine nickel catalysts (i.e., catalyst Ni10) with the structure shown in formula (IV) were prepared using α-diimine ligand compounds with the structure shown in formula (III). For specific synthetic methods, please refer to: Long Y, Chen Y, Chen A, et al. 2025. Ethylene (Co) Polymerization Catalyzed by α-Diimine Nickel Catalysts Bearing Ether Substituents. Polymer Science & Technology[J], 1(6): 563-568.

[0229] Formula (III) Formula (IV).

[0230] Application Example 1

[0231] The method for using different homogeneous α-diimine nickel catalysts prepared in Examples 10-18 and Comparative Example 1 in the homopolymerization of olefins includes: adding 28 mL of n-heptane and a dichloromethane solution containing 1 μmol of homogeneous α-diimine nickel catalyst to a pressure-resistant bottle of a 350 mL reactor (equipped with a magnetic stirrer, oil bath heating device, and thermometer) under a nitrogen atmosphere in a glove box. The reactor is connected to a high-pressure pipeline and the pipeline is evacuated. The reactor is controlled at different temperatures from 30-80°C using an oil bath, and 200 eq of Et₂AlCl is injected into the polymerization system using a syringe. After closing the valve and adjusting the ethylene pressure to 8 atm, the reaction is stopped after a specific time. The reactor is then opened, and the obtained polymer is vacuum-dried to obtain a white rubbery solid. Specifically, the experimental results of ethylene polymerization catalyzed by different homogeneous α-diimine nickel catalysts are shown in Table 3 below.

[0232] Table 3. Homogeneous α-diimine nickel catalyst for ethylene polymerization a

[0233]

[0234] a Polymerization conditions: 1.0 μmol nickel catalyst dissolved in 0.5 mL dichloromethane, 30 mL n-heptane, 0.8 MPa ethylene, 200 equivalents of Et₂AlCl, polymerization time 30 min. All active (Act) b . 10 6 g·mol -1 ·h -1 The molecular weight (M) is calculated from the average mass of the polymer obtained through polymerization.n c 10 4 g·mol -1 ) and molecular weight distribution index (PDI) c Branching degree (B) was determined by gel permeation chromatography. d ) by high-temperature nuclear magnetic resonance hydrogen spectrum ( 1 Detected by H NMR. e Melting point (T) m e The result was measured by a differential scanning calorimeter.

[0235] Application Example 2

[0236] The method for using different homogeneous α-diimine nickel catalysts prepared in Examples 10-18 and Comparative Example 1 in the copolymerization reaction of olefins includes: adding 18 mL of n-heptane and 5 μmol of a dichloromethane solution of different homogeneous α-diimine nickel catalysts to a pressure-resistant bottle of a 350 mL reactor (equipped with a magnetic stirrer, oil bath heating device, and thermometer) under a nitrogen atmosphere in a glove box. The reactor is connected to a high-pressure pipeline and the pipeline is evacuated. The reactor is controlled at 30°C using an oil bath. A mixed solution of 2000 eq of Et2AlCl and 2 mL of methyl 10-undecenoate is injected into the polymerization system using a syringe. The valve is closed, the ethylene pressure is adjusted to 8 atm (0.8 MPa), and the reaction is stopped after a specific time (30 min). The reactor is opened, and the obtained polymer is vacuum-dried to obtain a white powdery solid. Specifically, the experimental results of copolymerization of ethylene and methyl 10-undecenoate catalyzed by different homogeneous α-diimine nickel catalysts are shown in Table 4 below.

[0237] Table 4. Homogeneous α-diimine nickel catalyst for copolymerization of ethylene and methyl 10-undecenoate a

[0238]

[0239] a Polymerization conditions: 5.0 μmol nickel catalyst dissolved in 2.0 mL dichloromethane, 20 mL n-heptane, 0.8 MPa ethylene, 0.5 M polar monomer, 2000 equivalents of Et₂AlCl, polymerization time 30 min. All active (Act) b . 10 6 g·mol -1 ·h -1 The molecular weight (M) is calculated from the average mass of the polymer obtained through polymerization. n c 10 4 g·mol-1 ) and PDI c Measured by gel permeation chromatography. Insertion ratio (X) mol % d ) by high-temperature nuclear magnetic resonance hydrogen spectrum ( 1 Detected by H NMR. e The melting point was determined by differential scanning calorimetry.

[0240] Application Example 3

[0241] Polyethylene materials were prepared using different homogeneous α-diimine nickel catalysts obtained in Examples 10-18 at 50°C, and the prepared polyethylene materials were then laminated. The laminated samples were cut into dumbbell shapes, each 35 mm long, 2 mm wide, and 0.5 mm thick. Tensile cyclic recovery properties were then tested using a universal testing machine at a tensile rate of 10 mm / min, a tensile strain of 300%, and 10 cycles. Specific experimental results are shown below. Figure 15 As shown.

[0242] Figure 15 The diagram shows the elastic recovery properties of different polyethylene materials prepared using different catalysts in Application Example 3 of the present invention. In this diagram, (a) is catalyst Ni1, (b) is catalyst Ni2, (c) is catalyst Ni3, (d) is catalyst Ni4, (e) is catalyst Ni5, (f) is catalyst Ni6, (g) is catalyst Ni7, (h) is catalyst Ni8, and (i) is catalyst Ni9.

[0243] like Figure 15 As shown, polyethylene materials prepared using different homogeneous α-diimine nickel catalysts of the present invention at a polymerization temperature of 50°C exhibit good elastic recovery properties, while polyethylene materials prepared using Ni10 catalyst in Comparative Example 1 under the same conditions do not possess elastic cycling properties.

[0244] Comparative Application Example 1

[0245] The homogeneous α-diimine nickel catalyst prepared in Comparative Example 1 was used to prepare polyethylene material at 80℃, and the prepared polyethylene material was then pressed into a film. The pressed sample was cut into dumbbell shapes, with a length of 35 mm, a width of 2 mm, and a thickness of 0.5 mm. Tensile cyclic recovery performance was then tested using a universal testing machine at a tensile rate of 10 mm / min, a tensile strain of 300%, and 10 cycles. Specific experimental results are shown below. Figure 16 As shown.

[0246] Figure 16 The elastic recovery performance diagram of the polyethylene material in Application Example 1 is shown for comparison.

[0247] like Figure 16As shown, the Ni10 catalyst in Comparative Example 1 only exhibits elastic recovery properties in polyethylene materials prepared at a polymerization temperature of 80°C, while the present invention achieves this at 50°C. This demonstrates that the catalyst of the present invention can produce polyethylene elastomers with lower energy consumption. Furthermore, the elastic recovery rate of polyethylene catalyzed by the Ni4-Ni6 catalysts of the present invention is significantly higher than that of Comparative Example 1, reaching a maximum of 85%.

[0248] 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. An α-diimine ligand compound, characterized in that, It has a structure as shown in equation (I): Equation (I); R1 is selected from hydrogen, methoxy, or tert-butyl; R2 is selected from methyl, ethyl, or isopropyl; and R3 is selected from hydrogen or methyl.

2. The α-diimine ligand compound according to claim 1, characterized in that, The α-diimine ligand compound has a structure as shown in any one of formulas (I1) to (I9): Formula (I1) Equation (I2), Equation (I3), Equation (I4) Formula (I5), Equation (I6) Formula (I7) Formula (I8) Equation (I9).

3. A method for preparing an α-diimine ligand compound as described in any one of claims 1-2, characterized in that, include: Compound A and The reaction yields the first intermediate. The first intermediate reacts with 2,3-butanedione via a Schiff base reaction to yield the second intermediate. ; The second intermediate and compound B Following a Schiff base reaction, an α-diimine ligand compound with the structure shown in formula (I) was obtained.

4. An α-diimine nickel catalyst, characterized in that, It has a structure as shown in equation (II): Formula (II); R1 is selected from hydrogen, methoxy or tert-butyl; R2 is selected from methyl, ethyl or isopropyl; R3 is selected from hydrogen or methyl.

5. The α-diimine nickel catalyst according to claim 4, characterized in that, It has a structure as shown in any one of equations (II1) to (II9): Formula (Ⅱ1) Formula (Ⅱ2) Formula (Ⅱ3) Formula (Ⅱ4) Formula (Ⅱ5) Formula (Ⅱ6) Formula (Ⅱ7) Formula (Ⅱ8) Formula (Ⅱ9).

6. A method for preparing an α-diimine nickel catalyst as described in any one of claims 4-5, characterized in that, The α-diimine nickel catalyst is formed by coordination of the α-diimine ligand compound of any one of claims 1-2 with a bromide of divalent nickel; The bromide of the divalent nickel is selected from at least one of NiBr2 and (DME)NiBr2, wherein DME is ethylene glycol dimethyl ether.

7. The application of an α-diimine nickel catalyst as described in any one of claims 4-5 in the catalytic polymerization of olefin monomers, characterized in that, include: The co-catalyst and olefin monomer are added to the polymerization solvent, and then the α-diimine nickel catalyst is added to allow the olefin monomer to undergo a polymerization reaction.

8. The application according to claim 7, characterized in that, The olefin monomer is C2-C. 11 α-olefins, or the olefin monomers are C2-C 11 α-olefins and polar monomers; The polymerization solvent is selected from at least one of toluene, benzene, n-hexane, and n-heptane; The co-catalyst is selected from at least one of alkylaluminum and alkylaluminum chloride; The polymerization reaction includes homopolymerization or copolymerization; The polymerization reaction is carried out at a temperature of 30-80℃ and a pressure of 8-10 atm.

9. The application according to claim 8, characterized in that, The polar monomers include: At least one of methacrylic acid, methyl methacrylate, ethyl methacrylate, 10-undecenol, and 10-undecenic acid.

10. The application according to claim 8, characterized in that, The polyolefin material formed by the homopolymerization reaction has elastic recovery properties, wherein the elastic recovery rate is greater than 80%.

Images