Preparation method of sulfonyl gamma-butyrolactam

Abstract

The invention relates to the field of organic synthetic chemistry, in particular to a preparation method of sulfonyl gamma-butyrolactam, which comprises the following steps: by taking 1, 6-enyne, aryl diazonium salt and sodium pyrosulfite as reaction raw materials, adding a photocatalyst and an organic solvent, reacting in a nitrogen environment under the irradiation of visible light, and performing vacuum concentration and column chromatography separation to obtain the sulfonyl gamma-butyrolactam. The sulfonyl gamma-butyrolactam is obtained; the sulphone gamma-butyrolactam is prepared by adopting cheap and easily available sodium pyrosulfite as a sulfur source through a one-pot cyclization reaction under a mild condition; the preparation method has the advantages of easily available raw materials, simplicity in operation, greenness, environmental protection and the like.

Description

Technical Field

[0001] The invention relates to the field of organic synthetic chemistry, and in particular to a method for preparing sulfone-substituted gamma-butyrolactam. Background Art

[0002] The information disclosed in the background of the present invention is only intended to increase the understanding of the overall background of the present invention and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] γ-lactams are an important class of nitrogen-containing heterocycles that are widely found in drug molecules, biomolecules and some functional materials. Compounds containing butyrolactam structures can be used to prepare anticancer drugs for treating multiple myeloma and drugs for treating Alzheimer's disease; they have good activity in promoting intelligence, fighting aging and protecting the liver.

[0004] Sulfone functional groups are widely present in the core structural skeletons of various natural products and bioactive molecules. In particular, organic sulfur compounds containing sulfur sulfone structural units have strong anti-cancer and anti-tumor biological activities and show important medicinal value. In recent years, chemists have developed three methods for synthesizing sulfone-substituted γ-butyrolactam: the first method uses cuprous iodide as a catalyst and tert-butyl peroxide as an oxidant to promote the reaction of 1,6-enyne with sulfonyl hydrazide to synthesize sulfone-substituted γ-butyrolactam (Asian Journal of Organic Chemistry, 2019, 8, 2050-2053; CN110590637 A); the second method uses 1,6-enyne and aromatic azosulfone to react under heating conditions of 80 degrees to synthesize sulfone-substituted γ-butyrolactam (Chinese Chemical Letters 2021, 32, 136–139); the third method uses 1,6-enyne and sulfonyl chloride to selectively synthesize sulfone-substituted γ-butyrolactam under visible light irradiation with 2-methyltetrahydrofuran as a solvent (Green Chem., 2020, 22, 1388-1392; CN111348980 A). Although the above three methods can construct sulfone-substituted γ-butyrolactam, these methods have the disadvantages of metal residue, use of dangerous oxidants, cumbersome operation, high energy consumption, unstable raw materials and strong corrosion. Therefore, it is of certain practical value to develop a method for synthesizing sulfone-substituted γ-butyrolactam using mild conditions and simple steps. Summary of the invention

[0005] In order to solve the shortcomings and deficiencies of the prior art, the object of the present invention is to provide a method for preparing sulfone-substituted γ-butyrolactam, which has the advantages of simple operation and cheap and readily available raw materials.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A method for preparing sulfone-substituted γ-butyrolactam, the preparation method comprising: using 1,6-enyne shown in formula I, aryl diazonium salt shown in formula II and sodium pyrosulfite as reaction raw materials, adding a photocatalyst and an organic solvent, and performing a photoinduced reaction to obtain sulfone-substituted γ-butyrolactam shown in formula III; the reaction route is as follows: Among them, R 1 is hydrogen, chlorine, bromine, fluorine, methyl, tert-butyl or methoxy; R 2 is hydrogen or methyl; R 3 is hydrogen, methyl, fluorine, chlorine, bromine, methoxy or trifluoromethyl.

[0007] Furthermore, the molar ratio of the 1,6-enyne, aryl diazonium salt and sodium pyrosulfite is 1:(1-3):(1-3); and the amount of the photocatalyst is 1-5 mol% of the 1,6-enyne.

[0008] Furthermore, the molar ratio of the 1,6-enyne, the aryl diazonium salt and the sodium pyrosulfite is 1:2:2; and the amount of the photocatalyst is 1 mol% of the 1,6-enyne.

[0009] Furthermore, the photocatalyst is 1,2,3,5-tetrakis(carbazole-9-yl)-4,6-dicyanobenzene (4CzIPN), Rhodamine 6G, Na2-Eosin Y, Rhodamine B, Acridine Red or Eosin B.

[0010] Furthermore, the reaction is carried out under nitrogen conditions, at room temperature, for 12 h; and the light source is a 10-30 W blue LED lamp.

[0011] Furthermore, the organic solvent is tetrahydrofuran, 1,2-dimethoxyethane, 1,2-dichloroethane, N,N-dimethylformamide, acetonitrile or 1,4-dioxane.

[0012] Furthermore, the organic solvent is 1,2-dichloroethane.

[0013] Furthermore, after the reaction is completed, the reaction solution needs to be concentrated and separated by column chromatography.

[0014] Furthermore, the concentration step is: vacuum concentration under a pressure of 0.08 MPa to obtain a crude product free of organic solvent; The column chromatography separation step comprises: washing the crude product with a mixed eluent of petroleum ether and ethyl acetate, and performing column chromatography separation through a silica gel column, wherein the volume ratio of the petroleum ether to ethyl acetate is 5:1.

[0015] The preparation method provided by the present invention uses sodium pyrosulfite (Na2S2O5) as a sulfur source, combines aromatic diazonium salts and 1,6-enyne, uses an organic dye as a catalyst, and can prepare sulfone-substituted γ-butyrolactam at room temperature through a simple light-induced reaction. The preparation method has the advantages of simple operation and cheap and readily available raw materials.

[0016] Beneficial Effects The invention provides a method for preparing sulfone-substituted γ-butyrolactam. The preparation method uses sodium pyrosulfite as a sulfur source, adds an organic photocatalyst under visible light irradiation, and reacts with 1,6-enyne and an aryl diazonium salt to achieve efficient construction of sulfone-substituted γ-butyrolactam. The invention adopts cheap and readily available raw materials, and prepares the sulfone-substituted γ-butyrolactam through a one-pot cyclization reaction under mild conditions. The preparation method has the advantages of simple operation, readily available raw materials, mild reaction conditions, good functional group compatibility, and the like. DETAILED DESCRIPTION

[0017] The following description further describes the specific details of the present invention for a full understanding of the present invention. The terms used in the description of the present invention are only used to illustrate the advantages and features of the present invention and are not intended to limit the present invention.

[0018] Unless otherwise defined, all professional and scientific terms used in the present invention have the same meanings as those understood by those skilled in the art of the present invention. Unless otherwise specified, the drugs or reagents used in the present invention are used in accordance with the product instructions or in the conventional methods of use in the relevant field. The process of the present invention is further described based on the instructions and specific embodiments.

[0019] Example 1 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube, 1,2-dichloroethane was added under nitrogen protection, mixed evenly, and then stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, it was concentrated under vacuum (0.08 MPa) to no solvent to obtain a crude product, which was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil 55.9 mg, with a yield of 82%.

[0020] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Example 2 At room temperature, 1,6-enyne 1b (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4b, as a yellow oil (54.5 mg) with a yield of 76%.

[0021] The nuclear magnetic resonance results of the product 4b in this example are: 1 H NMR (400 MHz, CDCl3): d 7.87 (d, J = 7.6Hz, 2H), 7.65 - 7.58 (m, 3H), 7.49 (t, J = 7.7 Hz, 2H),7.11 - 7.07 (m, 2H),5.42 (s, 1H), 5.35 (s, 1H), 4.69 - 4.65 (m, 1H), 4.51 - 4.46 (m, 1H), 3.87(d, J = 14.3 Hz, 1H), 3.49 (d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz,CDCl3): d 174.1, 160.0 (d, J = 243.4 Hz), 142.1, 141.1, 134.9 (d, J = 2.9 Hz),133.6, 129.2, 127.6, 122.8 (d, J = 8.0 Hz), 115.7 (d, J = 22.3 Hz), 110.7, 63.4,52.6, 47.6, 27.0. ESI HRMS: calculated for C 19 H 19 FNO3S [M+H] + 360.1070, found360.1040. Example 3 At room temperature, 1,6-enyne 1c (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4c, as a yellow oil (54.2 mg) with a yield of 72%.

[0022] The nuclear magnetic resonance results of the product 4c in this example are: 1 H NMR (400 MHz, CDCl3): d 7.89 - 7.84 (m, 2H), 7.65 (d, J = 7.8 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.44 (d, J = 7.7 Hz,2H), 7.41 (t, J = 8.0 Hz, 2H), 5.44 (s, 1H), 5.37 (s, 1H), 4.75 - 4.65 (m, 1H), 4.54 - 4.46 (m, 1H), 3.89 (d, J = 14.2 Hz, 1H), 3.48 (d, J = 14.2 Hz, 1H), 1.40(s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.2, 142.3, 141.0, 138.7, 133.5, 129.4,129.3, 127.5, 125.1, 120.4, 110.3, 63.2, 52.1, 47.5, 26.8. ESI HRMS: calculated for 19 H 19 ClNO3S [M+H] + 376.0774, found 376.0786. Example 4 At room temperature, 1,6-enyne 1d (0.2 mmol), aryl diazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube, 1,2-dichloroethane was added under nitrogen protection, mixed evenly, and then stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, it was concentrated under vacuum (0.08 MPa) to no solvent to obtain a crude product, which was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4d, which was a yellow oil (65.3 mg) with a yield of 78%.

[0023] The nuclear magnetic resonance results of the product 4d in this example are: 1 H NMR (400 MHz, CDCl3): d 7.85 - 7.81 (m, 2H), 7.64 (d, J = 7.6 Hz, 2H), 7.52 (t, J = 7.5 Hz, 1H),7.43 (d, J = 7.6 Hz,2H), 7.46 (t, J = 7.9 Hz, 2H), 5.44 (s, 1H), 5.37 (s, 1H), 4.75 - 4.65 (m, 1H), 4.54 - 4.46 (m, 1H), 3.89 (d, J = 14.2 Hz, 1H), 3.48 (d, J = 14.2 Hz, 1H), 1.40(s, 3H); 13 C NMR (100 MHz, CDCl3): d 175.1, 143.1, 141.2, 139.1, 133.3, 130.1,129.8, 127.9, 125.3, 121.0, 110.7, 63.6, 52.5, 47.7, 26.9. ESI HRMS:calculated for C 19 H 19 BrNO3S [M+H] + 420.0269, found 420.0257. Example 5 At room temperature, 1,6-enyne 1e (0.2 mmol), aryl diazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4e, as a yellow oil (56.6 mg) with a yield of 75%.

[0024] The nuclear magnetic resonance results of the product 4e in this example are: 1 H NMR (400 MHz, CDCl3): d 7.90- 7.79 (m,2H), 7.65 (d, J = 7.5 Hz, 2H), 7.51 (t, J = 7.7 Hz, 1H),7.41 (d, J = 7.5 Hz, 2H),7.46 (t, J = 7.8 Hz, 2H), 5.49 (s, 1H), 5.39 (s, 1H), 4.77 - 4.66 (m, 1H), 4.56- 4.44 (m, 1H), 3.91 (d, J = 14.3 Hz, 1H), 3.51 (d, J = 14.3 Hz, 1H), 1.42(s, 3H), 1.37 (s, 9H); 13 C NMR (100 MHz, CDCl3): d ESI HRMS: calculated for C 23 H 28 NO3S [M+H] + 378.1790, found 378.1778. Example 6 At room temperature, 1,6-enyne 1f (0.2 mmol), aryl diazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4f, as a yellow oil (56.6 mg) with a yield of 77%.

[0025] The nuclear magnetic resonance results of the product 4f in this example are: 1 H NMR (400 MHz, CDCl3): d 7.86 (d, J = 8.7Hz, 2H), 7.63 (d, J = 7.6 Hz, 2H), 7.40 (t, J = 8.0 Hz, 2H), 7.16 (t, J = 7.6 Hz,1H), 6.90 (d, J = 8.7 Hz, 2H), 5.45 (s, 1H), 5.37 (s, 1H), 4.70 - 4.64 (m, 1H), 4.53 - 4.48 (m, 1H), 3.89 (d, J = 14.3 Hz, 1H), 3.83 (s, 3H), 3.47 (d, J = 14.3 Hz, 1H), 1.40 (s, 3H); 13 C NMR (100 MHz, CDCl3): d ESI HRMS: calculated for C 20 H 22 NO4S [M+H] + 372.1270, found 372.1245. Example 7 At room temperature, 1,6-enyne 1a (0.2 mmol), p-methylphenyldiazonium salt 2b (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the reaction was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to rapid column chromatography on a silica gel column to obtain 4 g of the product of this example, 50.4 mg of a yellow oil, with a yield of 71%.

[0026] The nuclear magnetic resonance results of the product 4g in this example are: 1 H NMR (500 MHz, CDCl3): d 7.73 (d, J = 8.2Hz, 2H), 7.65 (d, J = 7.9 Hz, 2H), 7.39 (t, J = 8.0 Hz, 2H), 7.25 (d, J = 8.1 Hz,2H), 7.19 (t, J = 7.4 Hz, 1H), 5.42 (s, 1H), 5.35 (s, 1H), 4.69 - 4.66 (m, 1H), 4.51 - 4.47 (m, 1H), 3.86 (d, J = 14.4 Hz, 1H), 3.47 (d, J = 14.4 Hz, 1H), 2.37(s, 3H), 1.38 (s, 3H); 13 C NMR (125 MHz, CDCl3): d ESI HRMS: calculated for C 20 H 22 NO3S [M+H] + 356.1320, found 356.1616. Example 8 At room temperature, 1,6-enyne 1a (0.2 mmol), p-fluorophenyl diazonium salt 2c (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to rapid column chromatography on a silica gel column to obtain the product of this example, sulfone γ-butyrolactam 4h, as a yellow oil 53.1 mg, with a yield of 74%.

[0027] The nuclear magnetic resonance results of the product 4h in this example are: 1 H NMR (400 MHz, CDCl3): d 7.89 - 7.85(m, 2H), 7.67 - 7.65 (m, 2H), 7.40 (t, J = 8.0 Hz, 2H), 7.20 (t, J = 7.4 Hz, 1H),7.13 (t, J = 8.6 Hz, 2H), 5.43 (s, 1H), 5.36 (s, 1H), 4.71 - 4.67 (m, 1H), 4.53- 4.49 (m, 1H), 3.88 (d, J = 14.4 Hz, 1H), 3.50 (d, J = 14.4 Hz, 1H), 1.39 (s,3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 165.8 (d, J = 254.6 Hz), 142.2, 138.8,137.2 (d, J = 3.1 Hz), 130.6 (d, J = 9.6 Hz), 129.0, 125.2, 120.6, 116.4 (d, J =22.6 Hz) 110.6, 63.5, 52.1, 47.9, 27.0. ESI HRMS: calculated for C 19 H 19 FNO3S [M+H]+ 360.1070, found 360.1078. Example 9 At room temperature, 1,6-enyne 1a (0.2 mmol), p-chlorophenyldiazonium salt 2d (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under irradiation with a 10 W blue LED lamp. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4i, as a yellow oil (57.8 mg) with a yield of 77%.

[0028] The nuclear magnetic resonance results of the product 4i in this example are: 1 H NMR (400 MHz, CDCl3): d 7.79 (d, J = 8.6Hz, 2H), 7.65 (d, J = 7.8 Hz, 2H), 7.45 - 7.39 (m, 4H), 7.20 (t, J = 7.4 Hz, 1H),5.43 (s, 1H), 5.36 (s, 1H), 4.71 - 4.66 (m, 1H), 4.53 - 4.49 (m, 1H), 3.88(d, J = 14.4 Hz, 1H), 3.50 (d, J = 14.4 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz,CDCl3): d ESI HRMS: calculated for C 19 H 19 ClNO3S [M+H] + 376.0774, found 376.0791. Example 10 At room temperature, 1,6-enyne 1a (0.2 mmol), p-bromophenyldiazonium salt 2e (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4j, as a yellow oil (56.1 mg) with a yield of 67%.

[0029] The nuclear magnetic resonance results of the product 4j in this example are: 1 H NMR (400 MHz, CDCl3): d 7.71 (d, J = 8.6Hz, 2H), 7.64 (d, J = 7.8 Hz, 2H), 7.60 (d, J = 8.6 Hz, 2H), 7.41 (t, J = 8.0 Hz,2H), 7.20 (t, J = 7.4 Hz, 1H), 5.43 (s, 1H), 5.36 (s, 1H), 4.70 - 4.65 (m, 1H), 4.53 - 4.48 (m, 1H), 3.87 (d, J = 14.4 Hz, 1H), 3.50 (d, J = 14.4 Hz, 1H), 1.39(s, 3H); 13 C NMR (100 MHz, CDCl3): d 173.9, 142.1, 140.0, 138.7, 132.5, 129.3,129.0, 129.0, 125.3, 120.5, 110.6, 63.4, 52.1, 47.9, 27.1. ESI HRMS: calculated for 19 H 19 BrNO3S [M+H] + 420.0269, found 420.0245. Embodiment 11 At room temperature, 1,6-enyne 1a (0.2 mmol), o-bromophenyldiazonium salt 2f (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under irradiation with a 10 W blue LED lamp. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4k, which was a yellow oil of 55.3 mg with a yield of 66%.

[0030] The nuclear magnetic resonance results of the product 4k in this example are: 1 H NMR (400 MHz, CDCl3): d 8.00 - 7.99(m, 1H), 7.81 - 7.79 (m, 1H), 7.71 - 7.66 (m, 3H), 7.42 - 7.34 (m, 3H), 7.22- 7.18 (m, 1H), 5.43 (s, 1H), 5.36 (s, 1H), 4.71 - 4.66 (m, 1H), 4.54 - 4.49(m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50 (d, J = 14.4 Hz, 1H), 1.40 (s, 3H); 13 CNMR (100 MHz, CDCl3): d 173.8, 142.8, 142.1, 138.7, 136.7, 130.8, 130.7, 129.0,126.4, 125.3, 123.1, 120.6, 110.7, 63.3, 52.1, 47.9, 27.0. HRMS:calculated for C 19 H 19 BrNO3S [M+H] + 420.0269, found 420.0283. Example 12 At room temperature, 1,6-enyne 1a (0.2 mmol), p-methoxyphenyl diazonium salt 2g (0.4 mmol), sodium pyrosulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the reaction was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4l, which was a yellow oil 55.6 mg with a yield of 75%.

[0031] The nuclear magnetic resonance results of the product 41 in this example are: 1 H NMR (400 MHz, CDCl3): d 7.76 (d, J = 8.9Hz, 2H), 7.65 (d, J = 7.7 Hz, 2H), 7.39 (t, J = 8.0 Hz, 2H), 7.18 (t, J = 7.5 Hz,1H), 6.89 (d, J = 8.9 Hz, 2H), 5.42 (s, 1H), 5.35 (s, 1H), 4.69 - 4.65 (m, 1H), 4.50 - 4.46 (m, 1H), 3.86 (d, J = 14.3 Hz, 1H), 3.80 (s, 3H), 3.46 (d, J = 14.3 Hz, 1H), 1.38 (s, 3H); 13 C NMR (100 MHz, CDCl3): d ESI HRMS: calculated for C 20 H 22 NO4S [M+H] + 372.1270, found 372.1245. Example 13 At room temperature, 1,6-enyne 1a (0.2 mmol), p-trifluoromethylphenyldiazonium salt 2h (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dichloroethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4m, as a yellow oil (55.6 mg) with a yield of 64%.

[0032] The nuclear magnetic resonance results of the product 4m in this example are: 1 H NMR (400 MHz, CDCl3): d 7.99 (d, J = 8.2Hz, 2H), 7.73 (d, J = 8.3 Hz, 2H), 7.64 (d, J = 8.1 Hz, 2H), 7.40 (t, J = 7.9 Hz,2H), 7.21 (t, J = 7.4 Hz, 1H), 5.44 (s, 1H), 5.37 (s, 1H), 4.72 - 4.67 (m, 1H), 4.54 - 4.50 (m, 1H), 3.91 (d, J = 14.4 Hz, 1H), 3.54 (d, J = 14.4 Hz, 1H), 1.39(s, 3H); 13 C NMR (100 MHz, CDCl3): d 173.8, 144.4, 142.1, 138.7, 135.3 (q, J = 32.9Hz), 129.1, 128.4, 126.3 (q, J = 3.7 Hz), 125.3, 123.1 (d, J = 271.5 Hz), 120.5,110.6, 63.3, 52.1, 48.0, 27.1. ESI HRMS: calculated for C 20 H 19F3NO3S [M+H] + 410.1038, found 410.1025. Embodiment 14 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.2 mmol), sodium metabisulfite 3 (0.2 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube, tetrahydrofuran was added under nitrogen protection, mixed evenly, and then stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, it was concentrated under vacuum (0.08 MPa) to no solvent to obtain a crude product, which was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil 27.9 mg, with a yield of 41%.

[0033] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 15 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.3 mmol), sodium metabisulfite 3 (0.3 mmol), and rhodamine 6G (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,4-dioxane was added under nitrogen protection and mixed evenly. Then, the reaction was stirred for 12 h under irradiation with a 30 W blue LED lamp. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to rapid column chromatography on a silica gel column to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil (35.5 mg) with a yield of 52%.

[0034] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Example 16 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.6 mmol), sodium metabisulfite 3 (0.6 mmol), and rhodamine 6G (5 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. Acetonitrile was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under irradiation with a 30 W blue LED lamp. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil (42.3 mg), with a yield of 62%.

[0035] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 17 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine 6G (2 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. 1,2-dimethoxyethane was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil (45.7 mg) with a yield of 67%.

[0036] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 18 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and alcohol-soluble eosin (Na2-Eosin Y) (the amount is 2 mol% of 1,6-enyne) were added in a 15 mL reaction tube in sequence, 1,2-dimethoxyethane was added under nitrogen protection, mixed evenly, and then stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, it was concentrated under vacuum (0.08 MPa) to no solvent to obtain a crude product, which was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, which was a yellow oil 45.7 mg, with a yield of 67%.

[0037] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H); 13C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 19 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and 4CzIPN (2 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube. N,N-dimethylformamide was added under nitrogen protection and mixed evenly. Then, the mixture was stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, the mixture was concentrated under reduced pressure (0.08 MPa) to a solvent-free state to obtain a crude product. The crude product was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to rapid column chromatography on a silica gel column to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil (45.7 mg) with a yield of 31%.

[0038] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J = 14.3 Hz, 1H), 1.39 (s, 3H);13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 20 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), and rhodamine B (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube, 1,2-dichloroethane was added under nitrogen protection, mixed evenly, and then stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, it was concentrated under vacuum (0.08 MPa) to no solvent to obtain a crude product, which was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil 38.2 mg, with a yield of 56%.

[0039] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d, J= 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 21 At room temperature, 1,6-enyne 1a (0.2 mmol), phenyldiazonium salt 2a (0.4 mmol), sodium metabisulfite 3 (0.4 mmol), acridine red (1 mol% of 1,6-enyne) were added in sequence in a 15 mL reaction tube, 1,2-dichloroethane was added under nitrogen protection, mixed evenly, and then stirred for 12 h under 10 W blue LED light. After the reaction was completed by TLC, it was concentrated under vacuum (0.08 MPa) to no solvent to obtain a crude product, which was then washed with a mixed eluent of petroleum ether and ethyl acetate in a volume ratio of 5:1, and subjected to silica gel column rapid column chromatography to obtain the product of this example, sulfone γ-butyrolactam 4a, as a yellow oil 35.5 mg, with a yield of 52%.

[0040] The nuclear magnetic resonance results of the product 4a in this example are: 1 H NMR (400 MHz, CDCl3): d 7.88 - 7.85 (m, 2H), 7.67 (d, J = 7.9 Hz, 2H), 7.58 (t, J = 7.4 Hz, 1H),7.48 (t, J = 7.7 Hz,2H), 7.40 (t, J = 8.0 Hz, 2H), 7.19 (t, J = 7.4 Hz, 1H), 5.41 (s, 1H), 5.35 (s,1H), 4.72 - 4.68 (m, 1H), 4.53 - 4.48 (m, 1H), 3.88 (d, J = 14.3 Hz, 1H), 3.50(d,J = 14.3 Hz, 1H), 1.39 (s, 3H); 13 C NMR (100 MHz, CDCl3): d 174.0, 142.2,141.1, 138.8, 133.6, 129.2, 129.0, 127.7, 125.2, 120.7, 110.6, 63.3, 52.2,47.8, 27.0. ESI HRMS: calculated for C 19 H 20 NO3S [M+H] + 342.1164, found 342.1171. Embodiment 22 The MTT experiment was used to detect the effect of the sulfone-substituted γ-butyrolactam compound prepared by the present invention on inhibiting the growth of liver cancer cell HepG2.

[0041] Experimental methods (1) Cell line: Hepatocellular carcinoma cell line: HepG2 (purchased from Cell Resource Center, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences).

[0042] (2) Experimental reagents: DMEM cell culture medium, PBS buffer, EDTA-0.25% trypsin, fetal bovine serum, penicillin-streptomycin mixture, MTT staining solution, DMSO solvent, etc.

[0043] (3) Experimental steps: The inhibitory effect of the sulfone-substituted γ-butyrolactam compound prepared by the present invention on liver cancer cell HepG2 was detected by MTT experiment: HepG2 liver cancer cells in logarithmic growth phase were digested with 0.25% trypsin, and single cell suspension was prepared with complete culture medium containing 10% FBS, 5000 cells were seeded in each well of 96-well plate, and incubated overnight in a constant temperature incubator at 37°C and 5% CO2. Culture medium containing different concentrations (6.25, 12.5, 25, 50, 100, 200, 300 μM) of sulfone-substituted γ-butyrolactam compound was added to the cells for culture, and 5-fluorouracil (5-FU) group was set as positive control, DMSO group (containing 0.1% DMSO) was set as negative control, and no cell group was set as blank control, with three replicate wells in each group. After 48 h, 20 μL of 5 mg / mL MTT solution was added. After 4 h, the culture medium was aspirated and 150 μL of DMSO was added. After incubation at 37°C for 10 min, the absorbance of each well at 490 nm was measured using an enzyme reader and the IC was calculated. 50 value.

[0044] The experimental results are shown in the following table: The values ​​in the table are the half inhibitory concentration (IC50 The results showed that the synthesized sulfone-substituted γ-butyrolactam compounds could inhibit the growth of liver cancer cells HepG2, among which compounds 4b, 4f, 4j and 4m had a half inhibitory concentration (IC 50 ) were 93.96, 94.30, 98.64 and 91.59 μM respectively, which are equivalent to the positive drug 5-fluorouracil (5-FU) and have strong anti-cancer ability. See the table below for specific data: Table 1 Effects of sulfone γ-butyrolactam compounds on the growth inhibition of HepG2 Comp. IC50(μM) 4a 132.33±2.48 4b 93.96±1.66 4c 115.71±4.30 4d 106.24±3.31 4e 126.27±2.33 4f 94.30±3.41 4g 114.13±1.68 4h 121.36±2.69 4i 108.29±3.27 4j 98.64±1.88 4k 128.34±1.69 4l 106.46±2.87 4m 91.59±3.54 positive control(5-FU) 93.79±1.31 Darkness - blank comparison - Each set of values ​​has three replicates. The above description only illustrates several embodiments of the present invention, and it cannot be understood as limiting the scope of the present invention. It should be pointed out that other persons in the art may make modifications, substitutions, improvements, etc. without departing from the concept and scope of the present invention, and these all belong to the protection scope of the present invention. Therefore, the scope of the present invention shall be based on the described claims.

Claims

1. A method for preparing sulfone-substituted γ-butyrolactam, It is characterized in that The preparation method comprises taking 1,6-enyne shown in formula I, aryl diazonium salt shown in formula II and sodium pyrosulfite as reaction raw materials, adding a photocatalyst and an organic solvent, and performing a photoinduced reaction to obtain sulfone-substituted γ-butyrolactam shown in formula III; the reaction route is as follows: ； Among them, R 1 is hydrogen, chlorine, bromine, fluorine, methyl, tert-butyl or methoxy; R 2 is hydrogen or methyl; R 3 is hydrogen, methyl, fluorine, chlorine, bromine, methoxy or trifluoromethyl.

2. The preparation method according to claim 1, It is characterized in that The molar ratio of the 1,6-enyne, aryl diazonium salt and sodium pyrosulfite is 1:(1-3):(1-3); the amount of the photocatalyst is 1-5 mol% of the amount of the 1,6-enyne.

3. The preparation method according to claim 2, It is characterized in that The molar ratio of the 1,6-enyne, the aryl diazonium salt and the sodium pyrosulfite is 1:2:2; and the amount of the photocatalyst is 1 mol% of the 1,6-enyne.

4. The preparation method according to claim 1, It is characterized in that The reaction was carried out under nitrogen conditions, at room temperature, for 12 h; the light source for the reaction was a 10-30 W blue LED lamp.

5. The preparation method according to claim 1, It is characterized in that The photocatalyst is 1,2,3,5-tetrakis(carbazole-9-yl)-4,6-dicyanobenzene, rhodamine 6G, alcohol-soluble eosin, rhodamine B, acridine red or eosin B; the organic solvent is tetrahydrofuran, 1,2-dimethoxyethane, 1,2-dichloroethane, N,N-dimethylformamide, acetonitrile or 1,4-dioxane.

6. The preparation method according to claim 5, It is characterized in that The organic solvent is 1,2-dichloroethane.

7. The preparation method according to claim 1, It is characterized in that After the reaction is completed, the reaction solution needs to be concentrated and separated by column chromatography.

8. The preparation method according to claim 7, It is characterized in that The concentration step comprises: performing vacuum decompression concentration treatment under a pressure of 0.08 MPa to obtain a crude product free of organic solvent; The column chromatography separation step comprises: washing the crude product with a mixed eluent of petroleum ether and ethyl acetate, and performing column chromatography separation through a silica gel column, wherein the volume ratio of the petroleum ether to ethyl acetate is 5:1.

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