A method for preparing a pyrrolidone derivative

Abstract

The application discloses a preparation method of a pyrrolidone derivative. Under the action of a non-precious bimetallic multifunctional catalyst, an acetylenic acid derivative shown in formula I is reacted with an amine, a nitro compound or a nitrile compound shown in formula II in a reaction solvent under the heating and stirring of hydrogen gas to prepare a pyrrolidone derivative shown in formula III, and a reaction formula is as follows: the non-precious bimetallic multifunctional catalyst is a nitrogen-doped carbon-based carrier NC derived from a metal-organic framework material ZIF-8 and an effective active ingredient embedded on the carrier NC; the effective active ingredient comprises two metals, one metal is Co, and the other metal is any one of Ni or Cu. The yield of the pyrrolidone derivative synthesized by the method can reach 77% to 100%. The method has the advantages of simple process, high selectivity of the target product, cleanness and environmental protection, small catalyst consumption, low cost, simple catalyst preparation, high catalytic stability and suitability for industrial production.

Description

Technical Field

[0001] This invention relates to a method for preparing pyrrolidone derivatives. Background Technology

[0002] Lignocellulosic biomass can be upgraded into a large number of important platform compounds, among which levulinic acid (LA) was recognized by the U.S. Department of Energy in 2004 as one of the 12 most competitive biomass platform molecules and can be easily obtained through acid-catalyzed dehydration. LA has been widely used to produce various value-added chemicals, such as γ-valerate lactone (GVL), succinic acid, 5-aminolevulinic acid, and N-substituted-5-methyl-2-pyrrolidone. N-substituted-5-methyl-2-pyrrolidone is a good reaction medium and can be used as an alternative to the typical aprotic polar solvent N-methylpyrrolidone. In addition, N-substituted-5-methyl-2-pyrrolidone can also be used as a solvent, surfactant, precursor in agrochemicals, and a key intermediate in printing inks and fiber dyes.

[0003] Currently, the industrial production method for pyrrolidone derivatives involves dehydrogenation-amination of γ-butyrolactone or butanediol with amines under harsh reaction conditions. Compared to these industrial methods that utilize fossil resources, the reductive amination of biomass-based platform molecules LA and amine compounds provides a sustainable production route for pyrrolidone derivatives. Chinese patent (CN107353237A) discloses a method for producing pyrrolidone derivatives from LA feedstocks and primary amines under the action of a carbon-based catalyst. Generally, amine compounds can be prepared from nitro / nitrile compounds through catalytic hydrogenation. To date, there are few studies on the one-pot synthesis of pyrrolidone derivatives from LA and its esters and amines / nitro / nitriles. In the literature (Green Chem. [J] 2020, 22, 7760), LA and amines / nitro / nitriles are converted into pyrrolidone derivatives under the action of an Ir-PVP catalyst. However, Ir-based catalysts are expensive and require large quantities (1.4 mol%), and for every metric amount of amine / nitro / nitrile compound in the reactants, two equivalents of LA are needed for the reaction, resulting in low atom economy. In the literature (Chem Catal. [J] 2022, 2, 178-194), the catalyst 0.75 Co-phen@C-800-HCl can simultaneously catalyze the one-pot synthesis of pyrrolidone derivatives from LA and amines / nitro / nitriles, but in the reductive amination reaction of LA and nitriles, additional NH3 is required, and the yield is low (65%–77%). Summary of the Invention

[0004] To address the aforementioned technical problems in existing technologies, the present invention aims to provide a method for preparing pyrrolidone derivatives. This invention provides an environmentally friendly method for the efficient one-pot synthesis of pyrrolidone derivatives from levulinic acid and its esters, along with amines / nitro compounds / nitrile compounds, in a hydrogen atmosphere under the action of a non-precious bimetallic multifunctional catalyst. The catalyst is inexpensive, simple to operate, requires low dosage, exhibits good stability, and results in high reaction yield and minimal waste.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for preparing pyrrolidone derivatives involves reacting an levulinic acid derivative of Formula I with an amine, nitro, or nitrile compound of Formula II in a reaction solvent under a hydrogen atmosphere using a non-precious bimetallic multifunctional catalyst, thereby obtaining a pyrrolidone derivative of Formula III. The reaction formula is as follows:

[0007]

[0008] In Formula I, R1 is H or C1-C4 alkyl, and in Formula II, R2 is selected from one of the following: C1-C10 alkyl, alkenyl or alkynyl, C3-C8 cycloalkyl, aryl or heteroaryl with unsubstituted or 1-3 substituents, wherein the substituent of the aryl or heteroaryl is halogen, C1-C4 alkyl or C1-C4 alkoxy.

[0009] The non-precious bimetallic multifunctional catalyst is a nitrogen-doped carbon-based support NC derived from the metal-organic framework material ZIF-8 and an effective active component embedded on the support NC; the effective active component includes two metals, one of which is Co and the other is either Ni or Cu.

[0010] This invention utilizes the non-noble metal Co in the aforementioned non-noble bimetallic multifunctional catalyst to promote the formation of ZIF-8, which serves as the main hydrogenation active site. The addition of a second non-noble metal, Ni or Cu, effectively promotes the formation of 0-valent Co. After high-temperature calcination, a graphite layer forms on the metal surface of ZIF-8, improving the catalyst's stability. By adjusting the calcination temperature to control the content of metals and N, a non-noble bimetallic multifunctional catalyst is formed, promoting the reduction of nitro / nitrile compounds and the reductive amination of LA and its esters, yielding high-yield pyrrolidone derivatives. The addition of the second non-noble metal creates an interaction between the bimetals, inhibiting Co aggregation, resulting in high Co dispersion, small size, and large specific surface area, thus improving the activity of the multifunctional catalyst. The catalyst of this invention exhibits high activity, good selectivity, and high product yield. Furthermore, the catalyst is recyclable, significantly reducing production costs.

[0011] The nitrogen-doped carbon-based support has a large specific surface area and pore volume, which allows non-precious metals to be uniformly dispersed on the support, thereby improving the activity of the non-precious bimetallic multifunctional catalyst. The nitrogen-doped carbon-based support has a large number of pores on its surface, which can promote substrate mass transfer and diffusion and adsorption of the effective active ingredients.

[0012] In the aforementioned non-precious bimetallic multifunctional catalyst, the content of Co is 2-10 wt%, and the molar ratio of Ni or Cu to Co is 1:2 to 2:1.

[0013] A suitable metal molar ratio leads to good metal-metal interactions, resulting in excellent catalytic performance. If the Co content is too low, the concentration of the active Co hydrogenation component is low, leading to low catalyst hydrogenation activity and hindering the hydrogenolysis of intermediates. Furthermore, an excessively low content of the second metal is detrimental to the formation of zero-valent Co and small-sized metal particles.

[0014] When the bimetallic content in a catalyst is too low, there are insufficient active sites, leading to incomplete reaction and very low product yield. However, when the bimetallic content is too high, the catalyst cost increases, and the excessive number of active sites makes over-hydrogenation or other side reactions more likely. In addition, when the bimetallic content is too high, the metal components on the catalyst surface are prone to aggregate, reducing the utilization of metal atoms.

[0015] Furthermore, the mass ratio of levulinic acid derivative to non-precious bimetallic multifunctional catalyst is 1:0.01 to 0.2.

[0016] If the amount of catalyst used in the reaction is too low, the reaction will be incomplete; however, if the amount of catalyst used is too high, a large number of by-products will be generated, which is detrimental to the reaction.

[0017] Further, the reaction solvent is methanol, ethanol, isopropanol, toluene, tetrahydrofuran, γ-valerolactone, or 1,4-dioxane, preferably ethanol or tetrahydrofuran. The volumetric amount of the solvent used is 1–20 mL / g based on the mass of the levulinic acid derivative.

[0018] Furthermore, the reaction conditions are as follows: the hydrogen pressure is 0.4–4 MPa, and the reaction is carried out at a temperature of 50–140°C for 5–36 hours.

[0019] Furthermore, the preferred hydrogen pressure is 1–4 MPa, and the reaction temperature is 120–130 °C.

[0020] Excessive hydrogen pressure will produce a large number of byproducts, which is detrimental to the reaction; if the reaction temperature is too low, the reduction and amination of LA and its esters and the hydrogenation of nitro / nitrile compounds will slow down, the reaction time will be longer, and the reaction will be incomplete; if the reaction temperature is too high, LA and its esters will undergo direct hydrogenation to form γ-valerolactone, and nitro / nitrile compounds will undergo irreversible transformation to form secondary amines, tertiary amines and other byproducts, resulting in a decrease in product yield.

[0021] The post-reaction processing method is as follows: the reaction solution is filtered, the filter cake is a non-precious bimetallic multifunctional catalyst, which is recovered and reused; the solvent is removed by distillation of the filtrate, and the residue is separated by column chromatography to obtain the product pyrrolidone derivative.

[0022] The preparation method of the non-noble bimetallic multifunctional catalyst is as follows: the second metal salt is Ni or Cu salt, Co salt, the second metal salt and Zn salt are dissolved in methanol to form solution A, 2-methylimidazole is dissolved in methanol to form solution B, solutions A and B are added to a hydrothermal synthesis reactor, ultrasonically mixed and then sealed, and the hydrothermal synthesis reactor is placed in an oven at 70-120°C for 6-24 hours; after the reactor body cools to room temperature, it is washed with methanol by centrifugation, dried at 70°C for 12 hours, ground into powder, and finally calcined at 700-1000°C under a nitrogen atmosphere for 1-4 hours to obtain the non-noble bimetallic multifunctional catalyst.

[0023] Furthermore, the molar ratio of the Co salt to the second metal salt is 1:2 to 2:1, and the ratio of the total mass of the Co salt and the second metal salt to the mass of 2-methylimidazole is 1:40 to 50, preferably 1:44 to 45.

[0024] Furthermore, the mass ratio of Zn salt to 2-methylimidazole is 1:4 to 5, and the methanol in the reaction solution is 5 to 20 mL / g based on the mass of 2-methylimidazole.

[0025] Furthermore, the preferred calcination temperature under the nitrogen atmosphere is 850–950°C.

[0026] The bimetallic soluble salt is decomposed at high temperature and reduced in situ under a nitrogen atmosphere. During the reduction process, some of the charge of the second metal is transferred to the Co metal, which reduces the chemical valence state of Co and thus forms more active 0-valent Co, thereby preparing the non-noble bimetallic multifunctional catalyst.

[0027] First, two metal salts, zinc nitrate, and 2-methylimidazole are hydrothermally synthesized, allowing the three metal cations to coordinate with 2-methylimidazole and self-assemble to form the ZIF-8 catalyst precursor. After calcination at high temperature in an inert gas atmosphere, the two metals form small-sized active metal particles, uniformly distributed on the support. The 2-methylimidazole forms a nitrogen-doped carbon-based support and a graphite layer on the metal surface. The zinc element sublimates at high temperature, leaving numerous channels in the nitrogen-doped carbon-based support, increasing the specific surface area of ​​the active metal, effectively improving the mass transfer of the substrate, and thus efficiently synthesizing pyrrolidone derivatives.

[0028] Furthermore, the Co salt is one of cobalt nitrate, cobalt acetate, or cobalt chloride, the second metal salt is the same anionic salt of the Co salt, and the Zn salt is zinc nitrate.

[0029] Compared with the prior art, the beneficial effects of this invention are reflected in:

[0030] 1. This invention develops a method for the one-pot synthesis of pyrrolidone derivatives from LA and its esters and amines / nitro compounds / nitriles under the action of a non-precious bimetallic multifunctional catalyst. Compared with metal catalysts in the prior art, it has a lower price, a simpler production method, and superior catalyst activity, selectivity and stability.

[0031] 2. The non-precious bimetallic multifunctional catalyst provided by this invention offers a simple, highly selective, and environmentally friendly application in the efficient synthesis of pyrrolidone derivatives from LA and its esters. The yield of pyrrolidone derivatives can reach over 77%.

[0032] 3. The non-precious bimetallic multifunctional catalyst of this invention exhibits good stability, is recyclable and reusable, requires low catalyst dosage, reduces costs, and is suitable for industrial production. In the embodiments of this invention, the calcination temperature during catalyst preparation reaches as high as 900℃. At this high temperature, the catalyst support is graphitized, greatly enhancing catalytic activity and stability. The volatilization of zinc atoms (zinc's boiling point is 907℃) leaves behind numerous pores, thereby improving mass transfer. Through extensive experiments, the applicant has found that catalysts prepared at calcination temperatures of only 500–600℃ exhibit significantly lower catalytic activity compared to this invention.

[0033] 4. The synthesis process of this invention is simple, the target product has high selectivity, it is clean and environmentally friendly, the amount of catalyst used is small, the cost is low, the catalyst preparation is simple, the catalytic stability is high, and it is suitable for industrial production. Detailed Implementation

[0034] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0035] The preparation method of the non-precious bimetallic multifunctional catalyst of the present invention takes a Co1Ni1@NC catalyst with a molar ratio of Co to Ni of 1:1 as an example: 1.116g of Zn(NO3)2·6H2O, 0.055g of Ni(NO3)2·6H2O, and 0.055g of Co(NO3)2·6H2O are weighed into a beaker, and 40mL of methanol is added to dissolve them, which is recorded as solution A; 4.928g of 2-methylimidazole is weighed into a beaker, and 40mL of methanol is added to dissolve it, which is recorded as solution B. Solutions A and B are poured into a 100mL hydrothermal synthesis reactor, sonicated for 10 minutes, sealed, and hydrothermally synthesized in a 90℃ oven for 12 hours. After the reactor body cools to room temperature, it is washed three times by centrifugation with methanol and dried at 70℃ for 12 hours. It is ground into powder and finally calcined at 900℃ under a nitrogen atmosphere for 2 hours to obtain the Co1Ni1@NC catalyst. The Co1Ni1@NC catalyst was tested by ICP-OES, and the total Co-Ni loading reached 5.8 wt%.

[0036] The Co1Ni2@NC catalyst was prepared by changing the molar ratio of Co to Ni to 1:2 as follows: 1.116 g of Zn(NO3)2·6H2O, 0.073 g of Ni(NO3)2·6H2O, and 0.037 g of Co(NO3)2·6H2O were weighed into a beaker, and 40 mL of methanol was added to dissolve them, which was designated as solution A. 4.928 g of 2-methylimidazole was weighed into a beaker, and 40 mL of methanol was added to dissolve it, which was designated as solution B. Solutions A and B were poured into a 100 mL hydrothermal synthesis reactor, sonicated for 10 minutes, sealed, and hydrothermally synthesized in a 90 °C oven for 12 hours. After the reactor cooled to room temperature, it was washed three times by centrifugation with methanol and dried at 70 °C for 12 hours. The powder was then ground and finally calcined at 900 °C under a nitrogen atmosphere for 2 hours to obtain the Co1Ni2@NC catalyst.

[0037] The Co2Ni1@NC catalyst was prepared by changing the molar ratio of Co to Ni to 2:1 as follows: 1.116 g of Zn(NO3)2·6H2O, 0.073 g of Co(NO3)2·6H2O, and 0.037 g of Ni(NO3)2·6H2O were weighed into a beaker, and 40 mL of methanol was added to dissolve them, which was designated as solution A. 4.928 g of 2-methylimidazole was weighed into a beaker, and 40 mL of methanol was added to dissolve it, which was designated as solution B. Solutions A and B were poured into a 100 mL hydrothermal synthesis reactor, sonicated for 10 minutes, sealed, and hydrothermally synthesized in a 90 °C oven for 12 hours. After the reactor cooled to room temperature, it was washed three times by centrifugation with methanol and dried at 70 °C for 12 hours. The powder was then ground and finally calcined at 900 °C under a nitrogen atmosphere for 2 hours to obtain the Co2Ni1@NC catalyst.

[0038] Using the same preparation method as the CoNi@NC catalyst, Ni(NO3)2·6H2O was replaced with an equal molar amount of Cu(NO3)2·6H2O to obtain the CoCu@NC catalyst.

[0039] The preparation method of the Co@NC catalyst of this invention is as follows: 1.116g Zn(NO3)2·6H2O and 0.11g Co(NO3)2·6H2O were weighed into a beaker, and 40mL of methanol was added to dissolve them, which was recorded as solution A. 4.928g 2-methylimidazole was weighed into a beaker, and 40mL of methanol was added to dissolve it, which was recorded as solution B. Solutions A and B were poured into a 100mL hydrothermal synthesis reactor, sonicated for 10 minutes, sealed, and hydrothermally synthesized in a 90℃ oven for 12 hours. After the reactor cooled to room temperature, it was washed three times by centrifugation with methanol and dried at 70℃ for 12 hours. It was ground into powder and finally calcined at 900℃ under a nitrogen atmosphere for 2 hours to obtain the Co@NC catalyst.

[0040] Using the same preparation method as the Co@NC catalyst, the Ni@NC catalyst was obtained by replacing Co(NO3)2·6H2O with an equal molar amount of Ni(NO3)2·6H2O.

[0041] The catalysts prepared above were applied in the following Examples 1-43.

[0042] Example 1:

[0043] 1.16 g (10 mmol) of levulinic acid and 1.07 g (10 mmol) of benzylamine were placed in a beaker and dissolved in 4 mL of tetrahydrofuran. The solution was then added to a 25 mL high-pressure reactor, along with 0.1 g of Co1Ni1@NC catalyst. The reactor was purged with nitrogen five times. The reaction was carried out at 130 °C and 3.0 MPa of hydrogen for 6 hours to obtain N-benzyl-5-methyl-2-pyrrolidone with a yield >99%.

[0044] Example 2:

[0045] 1.16 g (10 mmol) of levulinic acid and 1.07 g (10 mmol) of benzylamine were placed in a beaker and dissolved in 4 mL of tetrahydrofuran. The solution was then added to a 25 mL high-pressure reactor, along with 0.1 g of Co1Cu1@NC catalyst. The reactor was purged with nitrogen five times. The reaction was carried out at 130 °C and 3.0 MPa of hydrogen for 6 hours to obtain N-benzyl-5-methyl-2-pyrrolidone in 85% yield.

[0046] Example 3:

[0047] 1.30 g (10 mmol) of ethyl levulinate and 1.07 g (10 mmol) of benzylamine were placed in a beaker and dissolved in 4 mL of tetrahydrofuran. The solution was then added to a 25 mL high-pressure reactor, along with 0.1 g of Co1Ni1@NC catalyst. The reactor was purged five times with nitrogen gas. The reaction was carried out at 130 °C and 3.0 MPa with hydrogen gas for 10 hours to obtain N-benzyl-5-methyl-2-pyrrolidone with a yield of 98%.

[0048] Example 4:

[0049] 1.44 g (10 mmol) of ethyl levulinate and 1.07 g (10 mmol) of benzylamine were placed in a beaker and dissolved in 4 mL of tetrahydrofuran. The solution was then added to a 25 mL high-pressure reactor, along with 0.1 g of Co1Ni1@NC catalyst. The reactor was purged five times with nitrogen gas. The reaction was carried out at 130 °C and 3.0 MPa with hydrogen gas for 10 hours to obtain N-benzyl-5-methyl-2-pyrrolidone with a yield of 97%.

[0050] Examples 5-6:

[0051] Other operations were the same as in Example 1, except that the type of metal in the catalyst was changed, and the following reaction results were obtained (Table 1):

[0052] Table 1

[0053]

[0054]

[0055] Examples 7-8:

[0056] Other operations were the same as in Example 1, except that the molar ratio of Co and Ni metals in the catalyst was changed, resulting in the following reaction results (Table 2):

[0057] Table 2

[0058]

[0059] Examples 9-14:

[0060] Other operations are the same as in Example 1, except that the reaction solvent is changed, and the following reaction results are obtained (Table 3):

[0061] Table 3

[0062]

[0063]

[0064] Comparing Examples 1 and 9-14, it can be seen that the reaction solvent has a significant impact on the catalytic reaction results. In the reductive amination reaction of the present invention, a suitable solvent can highly disperse the reaction medium, which is beneficial for the exchange of matter between the catalyst surface and the reactants, improves mass transfer, and increases the reductive amination rate. According to Table 1, the preferred reaction solvents are tetrahydrofuran and ethanol.

[0065] Examples 15-16:

[0066] Other operations are the same as in Example 1, except that the reaction temperature is changed, and the following reaction results are obtained (Table 4):

[0067] Table 4

[0068]

[0069] Examples 17-26:

[0070] Other operations are the same as in Example 1, except that the number of times the catalyst is repeated is changed, and the following reaction results are obtained (Table 5):

[0071] Table 5

[0072]

[0073] Examples 27-31:

[0074] The other operations are the same as in Example 1, except that the type of primary amine and the reaction time are changed, and the following reaction results are obtained (Table 6):

[0075] Table 6

[0076]

[0077]

[0078] Example 32:

[0079] 1.16 g (10 mmol) of levulinic acid and 1.23 g (10 mmol) of nitrobenzene were placed in a beaker and dissolved in 4 mL of tetrahydrofuran. The solution was then added to a 25 mL high-pressure reactor, along with 0.1 g of Co1Ni1@NC catalyst. The reactor was purged five times with nitrogen gas. The reaction was carried out at 130 °C and 3.0 MPa with hydrogen gas for 36 hours to obtain N-phenyl-5-methyl-2-pyrrolidone with a yield of 97%.

[0080] Examples 33-37:

[0081] The other operations are the same as in Example 32, except that the type of nitroaromatic hydrocarbon and the reaction temperature are changed, and the following reaction results are obtained (Table 7):

[0082] Table 7

[0083]

[0084] Example 38:

[0085] 0.46 g (4 mmol) of levulinic acid and 0.49 g (4.8 mmol) of benzonitrile were placed in a beaker and dissolved in 4 mL of toluene. The solution was then added to a 25 mL high-pressure reactor, along with 0.13 g of Co1Ni1@NC catalyst. The reactor was purged five times with nitrogen gas. The reaction was carried out at 130 °C and 4.0 MPa with hydrogen gas for 24 hours to obtain N-benzyl-5-methyl-2-pyrrolidone in 84% yield.

[0086] Examples 39-43:

[0087] Other operations are the same as in Example 38, except that the types of nitrile compounds are changed, and the following reaction results are obtained (Table 8):

[0088] Table 8

[0089]

[0090] The contents described in this specification are merely an enumeration of the implementation forms of the inventive concept, and the scope of protection of this invention should not be regarded as limited to the specific forms described in the embodiments.

Claims

1. A method for preparing a pyrrolidone derivative, characterized in that, Under the action of a non-noble bimetallic multifunctional catalyst, the levulinic acid derivative shown in Formula I reacts with the amine, nitro, or nitrile compound shown in Formula II in a reaction solvent under a hydrogen atmosphere with heating and stirring to prepare the pyrrolidone derivative shown in Formula III. The reaction formula is as follows: ； In Formula I, R1 is H or C1-C4 alkyl, and in Formula II, R2 is selected from one of the following: C1-C10 alkyl, alkenyl or alkynyl, C3-C8 cycloalkyl, aryl or heteroaryl with unsubstituted or 1-3 substituents, wherein the substituent of the aryl or heteroaryl is halogen, C1-C4 alkyl or C1-C4 alkoxy. The non-precious bimetallic multifunctional catalyst is a nitrogen-doped carbon-based support NC derived from the metal-organic framework material ZIF-8 and an effective active component embedded on the support NC; the effective active component includes two metals, one of which is Co and the other is either Ni or Cu. In the aforementioned non-noble bimetallic multifunctional catalyst, the content of Co is 2~10wt%, and the molar ratio of Ni or Cu to Co is 1:2~2:1; The mass ratio of levulinic acid derivative to non-precious bimetallic multifunctional catalyst is 1:0.01~0.2; The reaction solvent is ethanol or tetrahydrofuran; The preparation method of the non-noble bimetallic multifunctional catalyst includes the following steps: the second metal salt is Ni or Cu salt; Co salt, the second metal salt and Zn salt are dissolved in methanol to form solution A; 2-methylimidazole is dissolved in methanol to form solution B; solutions A and B are added to a hydrothermal synthesis reactor; after ultrasonic mixing, the reactor is sealed; the hydrothermal synthesis reactor is placed in an oven at 70~120℃ for 6~24 hours; after the reactor body cools to room temperature, it is washed with methanol by centrifugation, dried, ground into powder, and finally calcined at 700~1000℃ under a nitrogen atmosphere for 1~4 hours to prepare the non-noble bimetallic multifunctional catalyst; In the preparation process of the non-noble bimetallic multifunctional catalyst, the calcination temperature under a nitrogen atmosphere is 850~950℃.

2. The method for preparing a pyrrolidone derivative according to claim 1, characterized in that, The volume of the solvent used is 1~20 mL / g based on the mass of the levulinic acid derivative.

3. The method for preparing a pyrrolidone derivative according to claim 1, characterized in that, The reaction conditions are: hydrogen pressure of 0.4~4MPa, reaction at 50~140℃ for 5~36 hours.

4. The method for preparing a pyrrolidone derivative according to claim 3, characterized in that, The reaction conditions are: hydrogen pressure of 1~4 MPa and reaction temperature of 120~130℃.

5. The method for preparing a pyrrolidone derivative according to claim 1, characterized in that, The ratio of the total mass of Co salt and the second metal salt to the mass of 2-methylimidazole is 1:40~50.

6. The method for preparing a pyrrolidone derivative according to claim 5, characterized in that, The ratio of the total mass of Co salt and the second metal salt to the mass of 2-methylimidazole is 1:44~45.

7. The method for preparing a pyrrolidone derivative according to claim 1, characterized in that, The mass ratio of Zn salt to 2-methylimidazole is 1:4~5, and the methanol in the reaction solution is 5~20 mL / g based on the mass of 2-methylimidazole.

8. The method for preparing a pyrrolidone derivative according to claim 1, characterized in that, The Co salt is one of cobalt nitrate, cobalt acetate, or cobalt chloride, the second metal salt is the same anionic salt of the Co salt, and the Zn salt is zinc nitrate.

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