CN110981808A

CN110981808A - Method for synthesizing diastereomer 2-imidazolone compound by silver and alkali concerted catalysis

Info

Publication number: CN110981808A
Application number: CN201911342472.4A
Authority: CN
Inventors: 刘振华; 陈慧敏; 刘建全; 高雯
Original assignee: Shandong Normal University
Current assignee: Shandong Normal University
Priority date: 2019-12-23
Filing date: 2019-12-23
Publication date: 2020-04-10
Anticipated expiration: 2039-12-23
Also published as: CN110981808B

Abstract

The invention discloses a method for synthesizing a diastereomer 2-imidazolone compound by concerted catalysis of silver and alkali, which comprises the steps of taking a compound 1 and a compound 2 as raw materials, taking a monovalent silver compound as a catalyst, and heating and reacting in an organic solvent under inert atmosphere to synthesize the 2-imidazolone compound; the chemical structural formula of the compound 1 is as follows:

the compound 2 is ethyl isocyanoacetate, and the chemical structural formula is as follows:

the chemical structural formula of the 2-imidazolinone compound is as follows:

wherein Ar is¹Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; ar (Ar)²Selected from aromatic hydrocarbonsA group, an electron donating or electron withdrawing substituted aryl group, an electron donating or electron withdrawing heteroaryl group. The invention can not only obtain the 2-imidazolone compound with high yield, but also easily obtain the diastereomer 2-imidazolone compound by adjusting the type of the added alkali.

Description

Method for synthesizing diastereomer 2-imidazolone compound by silver and alkali concerted catalysis

Technical Field

The invention belongs to the technical field of organic synthetic chemistry, and relates to a method for synthesizing a diastereomer 2-imidazolone compound by silver and alkali concerted catalysis.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

Nitrone compounds and isocyano compounds are two important general components in organic synthesis and are widely applied to construction of nitrogen-containing motifs. To date, significant progress has been made in such research. Meanwhile, among the methods disclosed, cycloaddition reaction is one of the most representative and powerful strategies for constructing N-heterocyclic compounds.

As far as the present inventors know, in the existing literature, there have been many reports of cycloaddition reaction of nitrones with isocyanides, as early as 1987, Jones reported a novel method of obtaining imines by inserting isonitriles into C- -H bonds of aromatic hydrocarbons catalyzed by iron, and subsequently, cinnoline and his colleagues found that quinazoline derivatives were obtained after refluxing toluene by providing an oxygen atmosphere under the catalysis of palladium acetate, and, at the same time, there has been reported in detail the cycloaddition reaction of nitrones with isocyanates, that is, a [3+3] cycloaddition reaction involving the action of nitrones and α -metallated isocyanates to form five-membered 2-imidazolidinones, and recently, reports on organic reactions involving isocyanates using silver salts as catalysts have been rapidly increased.

Despite these advances, the present inventors have discovered during their research that various deficiencies still exist in the synthesis: firstly, most of the five-membered ring products formed have poor reaction selectivity, especially in terms of diastereoselectivity and enantioselectivity; secondly, the catalyst has various types and complex reaction conditions, and the condition design is still difficult to be achieved; at the same time, the yield of the obtained product is low.

Disclosure of Invention

In order to solve the defects of the prior art, the invention aims to provide a method for synthesizing a diastereomer 2-imidazolone compound by concerted catalysis of silver and alkali, which not only can obtain the 2-imidazolone compound with high yield, but also can easily obtain the diastereomer 2-imidazolone compound.

In order to achieve the purpose, the technical scheme of the invention is as follows:

on the one hand, the method for synthesizing the 2-imidazolone compound takes a compound 1 and a compound 2 as raw materials, takes a monovalent silver compound as a catalyst, and synthesizes the 2-imidazolone compound by heating reaction in an organic solvent under inert atmosphere;

the chemical structural formula of the compound 1 is as follows:

the chemical structural formula of the 2-imidazolinone compound is as follows:

wherein Ar is¹Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; ar (Ar)²Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl.

On the other hand, the method for synthesizing the diastereomer 2-imidazolone compound by the concerted catalysis of silver and alkali takes a compound 1 and a compound 2 as raw materials, takes a monovalent silver compound as a catalyst, and synthesizes the diastereomer 2-imidazolone compound by heating reaction in an organic solvent under the action of the catalyst and the alkali in an inert atmosphere;

process for preparation of Compound 1The chemical structural formula is as follows:

the chemical structural formula of the diastereomer 2-imidazolinone compound is as follows:

wherein Ar is¹Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; ar (Ar)²Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; the base is an inorganic base.

Experiments show that when the inorganic base and the monovalent silver compound are catalyzed synergistically, the method is favorable for generating a trans-configuration product.

In a third aspect, a method for synthesizing a diastereomer 2-imidazolone compound by concerted catalysis of silver and alkali is characterized in that a compound 1 and a compound 2 are used as raw materials, a monovalent silver compound is used as a catalyst, and the mixture is heated and reacted in an organic solvent under the inert atmosphere and under the action of the catalyst and the alkali to synthesize the diastereomer 2-imidazolone compound;

the chemical structural formula of the compound 1 is as follows:

wherein Ar is¹Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; ar (Ar)²Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; the base is an organic base.

Experiments show that when the organic base and the monovalent silver compound are subjected to concerted catalysis, the method is favorable for generating a trans-configuration product.

The invention has the beneficial effects that:

the invention provides a new preparation method of five-membered ring products 2-imidazolone compounds with different configurations under cycloaddition reaction, which can synthesize products with two configurations of cis and trans through selecting alkali types in synthesis, has good selectivity in enantiomers and diastereoisomers, and simultaneously has good stability of the 2-imidazolone compounds with two different configurations; the silver salt and the alkaline substance are used for concerted catalysis, the catalyst is simple and easy to obtain, and the dominant configuration can be changed by changing the catalyst; DBU plays a dual role of a base and a ligand in one-time conversion, is favorable for the generation of cis-products, and Cs₂CO₃The generation of trans-products can be improved; in addition, the reaction conditions for preparing the 2-imidazolone compound under the method are easy to control, the yield of the reaction product is high, and the method is suitable for large-scale production.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a drawing of Compound A prepared in example 4 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 2 is a single crystal X-ray plot of Compound 3a prepared according to examples 9, 10 of the present invention;

FIG. 3 is a single crystal X-ray diagram of Compound 4a prepared according to examples 11 and 12 of the present invention;

FIG. 4 is a single crystal X-ray of Compound 3b prepared in example 13 of the present invention;

FIG. 5 shows an embodiment of the present inventionExample 13 preparation of Compound 3b¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 6 is a single crystal X-ray of Compound 4b prepared in example 13 of the present invention;

FIG. 7 is a photograph of Compound 4b prepared in example 14 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 8 is a photograph of Compound 3c prepared in example 15 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 9 is a photograph of Compound 4c, prepared according to example 16 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 10 is a photograph of Compound 3d prepared in example 17 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 11 is a photograph of Compound 4d prepared in example 18 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 12 is a drawing of Compound 3e, prepared according to example 19 of the invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 13 is a photograph of Compound 4e, prepared in example 20 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 14 is a photograph of Compound 3f prepared in example 21 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 15 is a photograph of Compound 4f prepared in example 22 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 16 is a photograph of Compound 3i prepared in example 23 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR;

FIG. 17 is a photograph of Compound 4i prepared in example 24 of the present invention¹Nuclear magnetic resonance spectrum of H-NMR.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

In view of the problems of low yield and difficulty in obtaining the diastereomer 2-imidazolone compound in the existing method for synthesizing the 2-imidazolone compound, the invention provides a method for synthesizing the diastereomer 2-imidazolone compound by the concerted catalysis of silver and alkali.

The invention provides a typical embodiment of a method for synthesizing 2-imidazolinone compounds, which comprises the steps of taking a compound 1 and a compound 2 as raw materials, taking a monovalent silver compound as a catalyst, and heating and reacting in an organic solvent under an inert atmosphere to synthesize the 2-imidazolinone compounds;

the chemical structural formula of the compound 1 is as follows:

the chemical structural formula of the 2-imidazolinone compound is as follows:

In one or more embodiments of this embodiment, the aryl group is selected from phenyl and substituted phenyl;

in this series of embodiments, the substituted phenyl is phenyl substituted with halo, alkyl, or cyano;

in this series of examples, the halogen is selected from F, Cl, Br;

in this series of examples, the alkyl group is selected from C₁-C₂A linear or branched alkyl group;

in this series of examples, the cyano group is selected from C₁-C₂A linear cyano group;

in this series of embodiments, the halogen is selected from Cl;

in this series of examples, said C₁-C₂The linear or branched alkyl group is selected from methyl;

in this series of examples, said C₁-C₂The straight-chain cyano group is selected from CN;

in one or more embodiments of this embodiment, Ar¹Selected from phenyl, 4-methylphenyl, 4-chlorophenyl; ar (Ar)²Selected from phenyl, 4-methylphenyl, 2-chlorophenyl, 4-cyanophenyl.

Silver salts according to the invention are monovalent silver-containing compounds, e.g. AgOAc, AgF, Ag₂O、Ag₂CO₃、AgBr、AgCl、AgNO₃And the like. In one or more embodiments of this embodiment, the monovalent silver salt is AgOAc, AgF, Ag for increasing the yield of the 2-imidazolinone compound₂O、Ag₂CO₃. Especially when the monovalent silver salt is Ag₂CO₃When the method is used, the yield of the generated 2-imidazolinone compound is higher.

The organic solvent is one or more selected from ethanol, toluene, N-dimethylformamide, 1, 2-dichloroethane, acetonitrile, 1, 4-dioxane, dimethyl sulfoxide, tetrahydrofuran and ethanol. In one or more embodiments of this embodiment, the organic solvent is one of acetonitrile, N-dimethylformamide, toluene, 1, 4-dioxahexaane, ethanol, which increases the conversion of the starting material while increasing the yield of the product. When the organic solvent is 1, 4-dioxane, the conversion rate of raw materials and the yield of products are higher.

In one or more embodiments of this embodiment, the reaction is carried out by heating to 25-90 ℃. This temperature can increase the conversion of the feedstock while increasing the yield of the product. When the reaction temperature is 80 + -8 deg.C, the conversion rate of the raw materials and the yield of the product can be further improved.

In one or more embodiments of this embodiment, the amount of catalyst added is 10-30% of the total mass of the feedstock.

In this series of examples, the amount of catalyst added was 20% of the total mass of the feedstock.

In one or more embodiments of this embodiment, the molar ratio of compound 1 to compound 2 is 1.9 to 2.1: 1.

In one or more embodiments of this embodiment, the reaction time is 0 to 10 hours, and the reaction time is not 0.

In this series of examples, the reaction time was 8. + -. 0.2 h.

In order to improve the purity of the 2-imidazolinone compound, in one or more embodiments of this embodiment, the reacted solution is added to an extraction solvent to extract an organic phase, the solvent in the organic phase is removed, and silica gel column chromatography is performed to obtain the 2-imidazolinone compound.

In the series of embodiments, the extraction solvent used for extraction is one or more of 1, 2-dichloroethane, toluene, nitromethane, ethyl acetate, diethyl ether, n-hexane, cyclohexane, petroleum ether or dichloromethane.

In this series of examples, the extraction solvent used for the extraction was dichloromethane.

In the series of embodiments, the extraction is performed 1-3 times, and 5-30 mL of the extraction solvent is used each time.

In this series of examples, the organic phase obtained was dried over anhydrous magnesium sulfate and the organic solvent was removed.

In the series of examples, the eluent of the silica gel column chromatography is petroleum ether and ethyl acetate.

In the series of embodiments, the volume ratio of the petroleum ether to the ethyl acetate is 1-20: 1-4.

In this series of examples, the volume ratio of petroleum ether to ethyl acetate was 10: 3. The eluent can be used for obtaining the 2-imidazolone compound with higher purity.

In another embodiment of the invention, a method for synthesizing a diastereomer 2-imidazolone compound by concerted catalysis of silver and alkali is provided, wherein a compound 1 and a compound 2 are used as raw materials, a monovalent silver compound is used as a catalyst, and the compound is heated and reacted in an organic solvent under the action of the catalyst and the alkali in an inert atmosphere to synthesize the diastereomer 2-imidazolone compound;

the chemical structural formula of the compound 1 is as follows:

The selection of conditions in this embodiment is consistent with the selection of conditions for the above-described method for synthesizing 2-imidazolinone compounds.

The inorganic base is Cs₂CO₃、K₂CO₃NaOH, etc. In one or more embodiments of this embodiment, the inorganic base is Cs₂CO₃、K₂CO₃. In this case, the formation of trans-configuration products is more favored. When the inorganic base is Cs₂CO₃In the process, the yield of the trans-configuration 2-imidazolone compound and the conversion rate of raw materials are improved.

In one or more embodiments of this embodiment, the inorganic base is 1 to 3 times the total mass of the starting materials. In this series of examples, the inorganic base is 2 times the total mass of the starting materials.

In a third embodiment of the invention, a method for synthesizing a diastereomer 2-imidazolone compound by concerted catalysis of silver and alkali is provided, wherein a compound 1 and a compound 2 are used as raw materials, a monovalent silver compound is used as a catalyst, and the diastereomer 2-imidazolone compound is synthesized by heating reaction in an organic solvent under the action of the catalyst and alkali in an inert atmosphere;

the chemical structural formula of the compound 1 is as follows:

The organic base is DABCO, DBU, triethylamine, PMDETA and the like. In one or more embodiments of this embodiment, the organic base is DBU, DABCO. In this case, the production of the product in the cis configuration is favored. When the organic base is DBU, the yield of the cis-configuration 2-imidazolone compound and the conversion rate of raw materials are obviously improved.

In order to make the technical solutions of the present invention more clearly understood by those skilled in the art, the technical solutions of the present invention will be described in detail below with reference to specific embodiments.

Example 1

Compound 1A, namely N-A-benzonitrone (0.0985g, 0.5mmol) (CAS: 1137-96-8), and compound 2A, namely ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and AgOAc (0.0083g, 0.05mmol) was added to the system, and heating and stirring were continued for 8 hours under nitrogen protection. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in a yield of 45%.

Example 2

Compound 1A, namely N-A-benzonitrone (0.0985g, 0.5mmol) and compound 2A, namely ethyl isocyanoacetate (0.0273mL, 0.25mmol) are added into 2mL of 1, 4-dioxane and dissolved at 80 ℃, AgF (0.0063g, 0.05mmol) is added into the system, and heating and stirring are continued for 8 hours under the nitrogen protection. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in a yield of 32%.

Example 3

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxan, dissolved at 80 deg.C, and then Ag was added to the system₂O (0.0116g, 0.05mmol) under the protection of nitrogen, and continuing to heatStirred for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in 54% yield.

Example 4

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxan, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), and stirring under nitrogen protection for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in 89% yield.

Example 5

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), and compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of DMF, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), and stirring under nitrogen protection for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in 74% yield.

Example 6

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), and compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of toluene, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), and stirring under nitrogen protection for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in a yield of 68%.

Example 7

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), and compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of acetonitrile, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), and stirring under nitrogen protection for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in a yield of 65%.

Example 8

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), and compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of ethanol, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), and stirring under nitrogen protection for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound a in 39% yield.

The reactions of examples 1 to 8 are as follows:

compound 3A:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 1: δ 7.45-7.16(m,9H),7.01-6.95(m,1H),6.19(s,1H),5.46(d, J ═ 3.7Hz,1H),4.29(q, J ═ 7.1,2.0Hz,2H),4.05(s,1H),1.33(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₈N₂O₃[M+Na]⁺:333.1197,found:333.1204.

Example 9

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxan, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3a in 89% yield.

Example 10

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxan, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g，0.05mmol)、K₂CO₃(0.0691g, 0.5mmol), and stirring was continued under nitrogen protection for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3a in a yield of 64%.

The reactions of examples 9-10 are as follows:

the resulting product 3a has a detailed structure of a single crystal X-ray pattern as shown in figure 2.

Example 11

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxan, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4a in 87% yield.

Example 12

Compound 1A, i.e., N-A-benzonitrone (0.0985g, 0.5mmol), compound 2A, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxan, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol) and DABCO (0.0561g, 0.5mmol) were stirred under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4a in a yield of 70%.

The reactions of examples 11-12 are as follows:

the resulting product 4a has a detailed structure of a single crystal X-ray pattern as shown in figure 3.

Example 13

Compound 1b, i.e., N-phenyl- α -o-chlorophenyl nitrone (0.1156g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3b in a yield of 90%.

The reaction formula is shown as follows:

the resulting product 3b has a detailed structure of a single crystal X-ray pattern as shown in figure 4.

Compound 3b:

¹h NMR (400MHz, Chloroform-d) is shown in FIG. 5: δ 7.46-7.39 (m,3H),7.34(d, J ═ 7.2,2.2Hz,1H),7.26-7.18(m,4H), 7.06-6.91 (m,1H), 6.32-6.10 (m,1H),5.93(d, J ═ 2.8Hz,1H),4.29(q, J ═ 7.2,2.3Hz,2H),4.04(d, J ═ 2.8Hz,1H),1.32(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₇ClN₂O₃[M+Na]⁺:367.0826,found:367.0806.

Example 14

Compound 1b, i.e., N-phenyl- α -o-chlorophenyl nitrone (0.1156g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours.TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4b in 89% yield.

The reaction formula is shown as follows:

the resulting product 4b has a detailed structure of a single crystal X-ray pattern as shown in figure 6.

Compound 4b:

¹h NMR (400MHz, Chloroform-d) is shown in FIG. 7: δ 7.35(d, J ═ 10.8,8.2,1.1Hz,3H),7.26 to 7.15(m,4H),7.11(t, J ═ 7.6,1.3Hz,1H),7.03 to 6.97(m,1H),6.18(d, J ═ 9.8Hz,1H),5.53(s,1H),4.81(d, J ═ 9.9Hz,1H),3.79(q, J ═ 10.7,7.1Hz,1H),3.54(q, J ═ 10.8,7.1Hz,1H),0.86(t, J ═ 7.2Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₇ClN₂O₃[M+Na]⁺:367.0826,found:367.0815.

Example 15

Compound 1c, i.e., N-phenyl- α -p-chlorophenyl nitrone (0.1156g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3c in 87% yield.

The reaction formula is shown as follows:

compound 3c:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 8: δ 7.42-7.37 (m,2H),7.33(s,4H), 7.26-7.20 (m,2H),7.01(d, J ═ 8.1,6.6Hz,1H),5.83(d, J ═ 18.2Hz,1H),5.46(t, J ═ 3.2Hz,1H),4.31(q, J ═ 7.1,1.4Hz,2H),4.02(t, J ═ 2.9Hz,1H),1.34(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₇ClN₂O₃[M+Na]⁺:367.0826,found:367.0830.

Example 16

Compound 1c, i.e., N-phenyl- α -p-chlorophenyl nitrone (0.1156g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4c in a yield of 91%.

The reaction formula is shown as follows:

compound 4c:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 9: δ 7.37-7.30 (m,2H), 7.29-7.17 (m,6H),7.00(t, J ═ 7.4Hz,1H),5.74(s,1H),5.55(d, J ═ 9.6Hz,1H),4.75(d, J ═ 9.6Hz,1H),3.84(q, J ═ 10.7,7.1Hz,1H),3.66(q, J ═ 10.8,7.2Hz,1H),0.92(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₇ClN₂O₃[M+Na]⁺:367.0826,found:367.0838.

Example 17

Compound 1d, i.e., N-phenyl- α -p-cyanophenylnitrone (0.1110g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3d with a yield of 90%.

The reaction formula is shown as follows:

compound 3d:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 10: δ 7.71-7.61 (m,2H),7.52(d, J ═ 8.3Hz,2H), 7.42-7.32 (m,2H), 7.28-7.20 (m,2H), 7.08-7.00 (m,1H), 5.93-5.64 (m,1H),5.55(d, J ═ 3.4Hz,1H),4.32(q, J ═ 7.1Hz,2H),4.02(d, J ═ 3.9Hz,1H),1.35(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₉H₁₇N₃O₃[M+Na]⁺:358.1168,found:358.1138.

Example 18

Compound 1d, i.e., N-phenyl- α -p-cyanophenylnitrone (0.1110g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction mixture was cooled and poured into 30mL of water, extracted with dichloromethane (3X 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then distilled off under reduced pressureThe organic solvent was removed to give a viscous liquid, which was chromatographed on silica gel (eluent V petroleum ether: V ethyl acetate 10:3) to give compound 4d in 88% yield.

The reaction formula is shown as follows:

compound 4d:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 11: δ 7.62-7.55 (m,2H), 7.46-7.41 (m,2H),7.31(d, J ═ 7.7Hz,2H), 7.25-7.18 (m,2H),7.02(t, J ═ 7.3Hz,1H),5.73(s,1H),5.63(d, J ═ 9.6Hz,1H),4.80(d, J ═ 9.5Hz,1H),3.83(q, J ═ 10.8,7.1Hz,1H),3.64(q, J ═ 10.8,7.2Hz,1H),0.91(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₉H₁₇N₃O₃[M+Na]⁺:358.1168,found:358.1145.

Example 19

Compound 1e, N-phenyl- α -p-methylphenyl nitrone (0.1055g, 0.5mmol), and compound 2a, ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3e in 92% yield.

The reaction formula is shown as follows:

compound 3e:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 12: δ 7.42(d, J ═ 8.7,1.2Hz,2H),7.29–7.12(m,6H),6.98(t,J＝7.3,1.1Hz,1H),5.98(s,1H),5.42(d,J＝3.8Hz,1H),4.29(q,J＝7.1,2.4Hz,2H),4.04(d,J＝3.7Hz,1H),2.31(s,3H),1.33(t,J＝7.1Hz,3H)；HRMS(ESI)m/zcalculated for C₁₉H₂₀N₂O₃[M+Na]⁺:347.1382,found:347.1399.

Example 20

Compound 1e, N-phenyl- α -p-methylphenyl nitrone (0.1055g, 0.5mmol), and compound 2a, ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4e in 89% yield.

The reaction formula is shown as follows:

compound 4e:

¹h NMR (400MHz, Chloroform-d), as shown in FIG. 13: δ 7.43-7.33 (m,2H), 7.24-7.13 (m,4H),7.07(d, J ═ 7.9Hz,2H),6.98(t, J ═ 7.4Hz,1H),5.53(d, J ═ 9.5Hz,1H),5.17(s,1H),4.73(d, J ═ 9.5Hz,1H),3.82(q, J ═ 10.7,7.2Hz,1H),3.63(q, J ═ 10.7,7.2Hz,1H),0.90(t, J ═ 7.2Hz, 3H); HRMS (ESI) m/z calculated for C₁₉H₂₀N₂O₃[M+Na]⁺:347.1382,found:347.1369.

Example 21

Compound 1f, i.e., N-p-chlorophenyl- α -phenylnitrone (0.1156g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3f in 87% yield.

The reaction formula is shown as follows:

compound 3f:

¹h NMR (400MHz, Chloroform-d) is shown in FIG. 14: δ 7.40-7.29 (m,7H),7.16(d, J ═ 8.5,1.4Hz,2H), 5.94-5.68 (m,1H),5.43(d, J ═ 3.8Hz,1H),4.31(q, J ═ 7.2,2.0Hz,2H),4.06(d, J ═ 3.7Hz,1H),1.34(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₇ClN₂O₃[M+Na]⁺:367.0826,found:367.0880.

Example 22

Compound 1f, i.e., N-p-chlorophenyl- α -phenylnitrone (0.1156g, 0.5mmol) and compound 2a, i.e., ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and then Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4f in a yield of 90%.

The reaction formula is shown as follows:

compound 4f:

¹h NMR (400MHz, Chloroform-d) is shown in FIG. 15: δ 7.35-7.30 (m,2H),7.27(q, J ═ 5.2,4.1Hz,5H), 7.19-7.13 (m,2H),5.54(d, J ═ 9.6Hz,1H),5.22(s,1H),4.74(d, J ═ 9.6Hz,1H),3.80(q, J ═ 10.8,7.1Hz,1H),3.58(q, J ═ 10.7,7.2Hz,1H),0.87(t, J ═ 7.2Hz, 3H); HRMS (ESI) m/z calculated for C₁₈H₁₇ClN₂O₃[M+Na]⁺:367.0826,found:367.0810.

Example 23

Compound 1i, N-p-methylphenyl- α -phenylnitrone (0.1055g, 0.5mmol) and compound 2a, ethyl isocyanoacetate (0.0273mL, 0.25mmol) were added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and Ag was added to the system₂CO₃(0.0138g，0.05mmol)、Cs₂CO₃(0.1629g, 0.5mmol), and stirring was continued under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 3i in 88% yield.

The reaction formula is shown as follows:

¹h NMR (400MHz, Chloroform-d) is shown in FIG. 16: δ 7.42-7.24 (m,7H),7.01(d, J ═ 8.3Hz,2H), 5.88-5.65 (m,1H),5.42(d, J ═ 3.9Hz,1H),4.30(q, J ═ 7.1,2.2Hz,2H),4.05(d, J ═ 3.9Hz,1H),2.22(s,3H),1.34(t, J ═ 7.1Hz, 3H); HRMS (ESI) m/z calculated for C₁₉H₂₀N₂O₃[M+Na]⁺:347.1382,found:347.1369.

Example 24

Compound 1i, i.e. N-p-methylphenyl- α -phenylnitrone (0.1055g,0.5mmol), Compound 2a, ethyl isocyanoacetate (0.0273mL, 0.25mmol) was added to 2mL of 1, 4-dioxahexane, dissolved at 80 deg.C, and Ag was added to the system₂CO₃(0.0138g, 0.05mmol), DBU (0.0761g, 0.5mmol), and stirring under nitrogen for 8 hours. TLC detects the disappearance of the substrate and the reaction is finished. The reaction solution was cooled and poured into 30mL of water, and extracted with dichloromethane (3 × 10mL), the organic phases were combined, dried over anhydrous magnesium sulfate, filtered with suction, and then the organic solvent was distilled off under reduced pressure to obtain a viscous liquid, which was subjected to silica gel column chromatography (eluent V petroleum ether: V ethyl acetate ═ 10:3) to obtain compound 4i in 87% yield.

The reaction formula is shown as follows:

compound 4i:

¹h NMR (400MHz, Chloroform-d) is shown in FIG. 17: δ 7.33-7.19 (m,7H),7.01(d, J ═ 8.3Hz,2H),5.54(d, J ═ 9.6Hz,1H),5.30(s,1H),4.73(d, J ═ 9.7Hz,1H),3.79(q, J ═ 10.7,7.2Hz,1H),3.58(q, J ═ 10.7,7.2Hz,1H),2.21(s,3H),0.86(t, J ═ 7.2Hz, 3H); HRMS (ESI) m/z calculated for C₁₉H₂₀N₂O₃[M+Na]⁺:347.1382,found:347.1392.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for synthesizing 2-imidazolinone compounds is characterized in that a compound 1 and a compound 2 are used as raw materials, a monovalent silver compound is used as a catalyst, and the 2-imidazolinone compounds are synthesized by heating reaction in an organic solvent under inert atmosphere;

the chemical structural formula of the compound 1 is as follows:

the chemical structural formula of the 2-imidazolinone compound is as follows:

2. A method for synthesizing diastereomer 2-imidazolone compounds by silver and alkali concerted catalysis is characterized in that a compound 1 and a compound 2 are used as raw materials, a univalent silver compound is used as a catalyst, and the heating reaction is carried out in an organic solvent under the inert atmosphere and under the action of the catalyst and alkali to synthesize the diastereomer 2-imidazolone compounds;

the chemical structural formula of the compound 1 is as follows:

wherein Ar is¹Selected from aryl, electron-donating or electron-withdrawing substituted aryl, electron-donatingA heteroaryl group which is electron withdrawing; ar (Ar)²Selected from aryl, electron donating or electron withdrawing substituted aryl, electron donating or electron withdrawing heteroaryl; the base is an inorganic base.

3. The method according to claim 2, wherein the inorganic base is Cs₂CO₃、K₂CO₃(ii) a Preferably, the inorganic base is Cs₂CO₃。

4. A method for synthesizing diastereomer 2-imidazolone compounds by silver and alkali concerted catalysis is characterized in that a compound 1 and a compound 2 are used as raw materials, a univalent silver compound is used as a catalyst, and the heating reaction is carried out in an organic solvent under the inert atmosphere and under the action of the catalyst and alkali to synthesize the diastereomer 2-imidazolone compounds;

the chemical structural formula of the compound 1 is as follows:

5. The process as claimed in claim 4, wherein the organic base is DBU, DABCO; preferably, the organic base is DBU.

6. The process as claimed in claim 1,2 or 4, wherein the aryl group is selected from phenyl and substituted phenyl;

preferably, the substituted phenyl is phenyl substituted by halogen, alkyl or cyano;

preferably, the halogen is selected from F, Cl, Br;

preferably, the alkyl group is selected from C₁-C₂A linear or branched alkyl group;

preferably, the cyano group is selected from C₁-C₂A linear cyano group;

preferably, the halogen is selected from Cl;

preferably, said C₁-C₂The linear or branched alkyl group is selected from methyl;

preferably, said C₁-C₂The straight-chain cyano group is selected from CN;

preferably, Ar is¹Selected from phenyl, 4-methylphenyl, 4-chlorophenyl; ar (Ar)²Selected from phenyl, 4-methylphenyl, 2-chlorophenyl, 4-cyanophenyl.

7. The method of claim 1,2 or 4, wherein the monovalent silver salt is AgOAc, AgF, Ag₂O、Ag₂CO₃(ii) a Preferably, the monovalent silver salt is Ag₂CO₃；

Or the organic solvent is one of acetonitrile, N-dimethylformamide, toluene, 1, 4-dioxane and ethanol; preferred organic solvents are 1, 4-dioxahexaalkane;

or heating to 25-90 ℃ for reaction; preferably, the temperature of the reaction is 80. + -. 8 ℃.

8. The method as claimed in claim 1,2 or 4, wherein the amount of the catalyst added is 10-30% of the total mass of the raw materials;

preferably, the addition amount of the catalyst is 20% of the total mass of the raw materials;

or the molar ratio of the compound 1 to the compound 2 is 1.9-2.1: 1;

or the reaction time is 0-10 h and is not 0;

preferably, the reaction time is 8. + -. 0.2 h.

9. The method according to claim 1,2 or 4, wherein the solution after the reaction is added to an extraction solvent to extract the solution to obtain an organic phase, the solvent in the organic phase is removed, and silica gel column chromatography is performed to obtain the 2-imidazolinone compound;

preferably, the extraction solvent used for extraction is one or more of 1, 2-dichloroethane, toluene, nitromethane, ethyl acetate, diethyl ether, n-hexane, cyclohexane, petroleum ether or dichloromethane;

preferably, the extraction solvent used for extraction is dichloromethane;

preferably, the extraction is carried out for 1-3 times, and 5-30 mL of extraction solvent is used each time;

preferably, the obtained organic phase is dried by adopting anhydrous magnesium sulfate, and then the organic solvent is removed;

preferably, the eluent of the silica gel column chromatography is petroleum ether and ethyl acetate;

preferably, the volume ratio of the petroleum ether to the ethyl acetate is 1-20: 1-4;

preferably, the volume ratio of petroleum ether to ethyl acetate is 10: 3.

10. The method according to claim 2 or 4, wherein the amount of the alkali is 1 to 3 times the total mass of the raw materials; preferably, the amount of base is 2 times the total mass of the starting materials.