Method for preparing 2-phenylbenzene-1, 3-sulfur oxygen heterocyclic hexadiene-4-ketone through HI catalysis

Abstract

The invention relates to the technical field of fine chemical engineering, in particular to a method for preparing 2-phenylbenzene-1, 3-sulfur oxygen heterocyclic hexadiene-4-ketone through HI catalysis. The yield of the 2-phenylbenzo-1, 3-sulfur oxygen heterocyclic hexadiene-4-ketone synthesized by a conventional method is relatively low. In order to solve the technical problems, the invention provides the method for preparing the 2-phenylbenzene-1, 3-sulfur oxygen heterocyclohexadiene-4-ketone through HI catalysis, the method comprises the following steps: adding thiosalicylic acid, benzaldehyde and HI into an organic solvent, stirring and reacting at the temperature higher than room temperature to obtain the 2-phenylbenzene-1, 3-sulfur oxygen heterocyclohexadiene-4-ketone, and then adding the 2-phenylbenzene-1, 3-sulfur oxygen heterocyclohexadiene-4-ketone into the organic solvent to obtain the 2-phenylbenzene-1, 3-sulfur oxygen heterocyclohexadiene-4-ketone. In the method, the reaction raw materials are easy to obtain, the operation is simple and convenient, the equipment requirement is low, the yield is up to 95%, and the method has a better application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of fine chemicals, and in particular to a method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis. Background Art

[0002] 2-Phenylbenzo-1,3-thioxadien-4-one is an important class of organic sulfur-containing oxygen heterocyclic compounds with significant biological activities, including insecticide and antibacterial effects. In addition, this compound can also be used as a food additive.

[0003] At present, there are few methods for synthesizing 2-phenylbenzo-1,3-thioxadiene-4-one. The early synthesis method mainly used 2-benzylsulfinylbenzoic acid as the raw material and used the Pummerer reaction to prepare 2-phenylbenzo-1,3-thioxadiene-4-one; then, 2-benzylthiobenzoic acid was used as the raw material and Selectfluor or iodophenyldiacetic acid was added to achieve the preparation of the product. The main drawback of these methods is that 2-benzylsulfinylbenzoic acid and 2-benzylthiobenzoic acid need to be prepared in advance.

[0004] Recently, the target product can be quickly prepared using benzothiol-3-one and benzaldehyde as raw materials, chromium dichloride as a metal catalyst, potassium carbonate and 1,2-bis(diphenylphosphine)ethane as additives, but the yield is low, only 45%.

[0005] Although there are literature reports on the use of thiosalicylic acid and benzaldehyde as raw materials to prepare 2-phenylbenzo-1,3-thiooxadiene-4-one, the reported yield is only 33% and no specific synthesis method is provided (Bulletin de la Societe Chimique de France, 1975, 206; Tetrahedron, 1980, 36, 3309).

[0006] Based on the above problems, we designed a method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by the HI-catalyzed reaction of thiosalicylic acid and benzaldehyde, which provides a new idea for the synthesis of this type of active compounds and has good potential application value. Summary of the invention

[0007] The problem in the prior art is that the yield of 2-phenylbenzo-1,3-thioxan-4-one synthesized by conventional methods is low. In view of the above technical problems, the present invention provides a method for preparing 2-phenylbenzo-1,3-thioxan-4-one by HI catalysis, which comprises the following preparation steps:

[0008] Thiosalicylic acid, benzaldehyde and HI are added to an organic solvent, and the mixture is stirred and reacted at a temperature higher than room temperature. After the reaction is completed, the reaction solution is purified to obtain 2-phenylbenzo-1,3-thioxadiene-4-one. The structural formula of the 2-phenylbenzo-1,3-thioxadiene-4-one is as follows:

[0009]

[0010] Ph in the above structural formula represents a benzene ring.

[0011] Preferably, the purification method is to sequentially concentrate the reaction solution and separate it by column chromatography.

[0012] Preferably, the reaction temperature is 40-120°C.

[0013] Preferably, the reaction temperature is 40°C.

[0014] Preferably, during the reaction, the molar ratio of thiosalicylic acid to benzaldehyde and HI is 0.2:0.2-0.6:0.04-0.3.

[0015] Preferably, the usage ratio of thiosalicylic acid to the organic solvent is 0.2 mmol:1-3 mL.

[0016] Preferably, the usage ratio of thiosalicylic acid to the organic solvent is 0.2 mmol:2 mL.

[0017] Preferably, during the reaction, the molar ratio of thiosalicylic acid to benzaldehyde and HI is 0.2:0.5:0.04.

[0018] Preferably, the organic solvent includes at least one of dichloromethane, chloroform, 1,2-dichloroethane, acetonitrile, ethyl acetate, anhydrous methanol, tetrahydrofuran, and dimethyl sulfoxide.

[0019] Preferably, the reaction time is 1 h.

[0020] The present invention has the following beneficial effects:

[0021] The invention provides a method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis, which has easy-to-obtain reaction raw materials, simple operation, low equipment requirements, and a yield of up to 95%, and has good application prospects. DETAILED DESCRIPTION

[0022] The present invention is described in detail below with reference to the examples. However, it should be understood that the following examples are only illustrative of the embodiments of the present invention, and are not intended to limit the scope of the present invention.

[0023] Example 1

[0024] Thiosalicylic acid (0.2mmol, 30.8mg), benzaldehyde (0.3mmol, 31μL), dichloromethane (2.0mL), and HI (0.2mmol, 24μL) were added to a 25mL sealed tube in sequence, and stirred at 100°C for 1 hour before the reaction was completed. After the reaction, the reaction solution was concentrated and separated by column chromatography in sequence to obtain 2-phenylbenzo-1,3-thioxadiene-4-one with a yield of 60%. The structure of the target product was confirmed by nuclear magnetic hydrogen spectrum. The reaction process of the above reaction is as follows:

[0025]

[0026] The NMR data of the target product are as follows:

[0027] 1 H NMR (300MHz, CDCl3) δ8.22 (d, J = 8.0Hz, 1H), 7.62-7.58 (m, 2H), 7.54-7.49 (m, 1H), 7.46-7.31 (m, 5H), 6.57 (s, 1H).

[0028] Screening HI dosage

[0029] Example 2 is the same as Example 1, except that the amount of HI used in Example 2 is 0. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 0%.

[0030] Example 3 is the same as Example 1, except that the amount of HI used in Example 3 is 0.04 mmol. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 65%.

[0031] Example 4 is the same as Example 1, except that the amount of HI used in Example 4 is 0.1 mmol. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 60%.

[0032] Screening the dosage of benzaldehyde

[0033] Example 5 is the same as Example 3, except that the amount of benzaldehyde used in Example 5 is 0.2 mmol. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 30%.

[0034] Example 6 is the same as Example 3, except that the amount of benzaldehyde used in Example 6 is 0.4 mmol. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 70%.

[0035] Example 7 is the same as Example 3, except that the amount of benzaldehyde used in Example 7 is 0.5 mmol. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 90%.

[0036] Example 8 is the same as Example 3, except that the amount of benzaldehyde used in Example 8 is 0.6 mmol. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 89%.

[0037] Screening solvent types

[0038] Example 9 is the same as Example 7, except that Example 9 uses the same volume of chloroform to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 85%.

[0039] Example 10 is the same as Example 7, except that Example 10 uses the same volume of 1,2-dichloroethane to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 80%.

[0040] Example 11 is the same as Example 7, except that the same volume of acetonitrile is used in Example 11 to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 80%.

[0041] Example 12 is the same as Example 7, except that the same volume of ethyl acetate is used to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 52%.

[0042] Example 13 is the same as Example 7, except that the same volume of anhydrous methanol is used to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 15%.

[0043] Example 14 is the same as Example 7, except that Example 14 uses the same volume of tetrahydrofuran to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 0%.

[0044] Example 15 is the same as Example 7, except that Example 15 uses the same volume of dimethyl sulfoxide to replace the dichloromethane in Example 7. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 0%.

[0045] Screening reaction temperature

[0046] Example 16 is the same as Example 7, except that the reaction temperature in Example 16 is 20° C. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 0%.

[0047] Example 17 is the same as Example 7, except that the reaction temperature in Example 17 is 40° C. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 95%.

[0048] Example 18 is the same as Example 7, except that the reaction temperature in Example 18 is 60° C. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 93%.

[0049] Example 19 is the same as Example 7, except that the reaction temperature in Example 19 is 80° C. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 90%.

[0050] Example 20 is the same as Example 7, except that the reaction temperature in Example 20 is 120° C. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 85%.

[0051] Screening response time

[0052] Example 21 is the same as Example 17, except that the reaction time in Example 21 is 0.5 h. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 85%.

[0053] Example 22 is the same as Example 17, except that the reaction time in Example 22 is 3 hours. The yield of 2-phenylbenzo-1,3-thioxadien-4-one is 80%.

[0054] Screening solvent dosage

[0055] Example 23 is the same as Example 17, except that the amount of dichloromethane used in Example 23 is 1 mL. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 80%.

[0056] Example 24 is the same as Example 17, except that the amount of dichloromethane used in Example 24 is 3 mL. The yield of 2-phenylbenzo-1,3-thioxadiene-4-one is 83%.

[0057] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis, characterized in that: The method comprises the following preparation steps: Thiosalicylic acid, benzaldehyde and HI are added to an organic solvent, and the mixture is stirred and reacted at a temperature higher than room temperature. After the reaction is completed, the reaction solution is purified to obtain 2-phenylbenzo-1,3-thioxadiene-4-one. The structural formula of the 2-phenylbenzo-1,3-thioxadiene-4-one is as follows: Ph in the above structural formula represents a benzene ring.

2. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 1, characterized in that: The purification method is to concentrate the reaction solution and separate it by column chromatography in sequence.

3. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 1, characterized in that: The reaction temperature is 40-120°C.

4. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 3, characterized in that: The reaction temperature was 40°C.

5. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 1, characterized in that: During the reaction, the molar ratio of thiosalicylic acid to benzaldehyde and HI is 0.2:0.2-0.6:0.04-0.

3.

6. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 5, characterized in that: The usage ratio of thiosalicylic acid to the organic solvent is 0.2mmol:1-3mL.

7. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 6, characterized in that: The dosage ratio of thiosalicylic acid to the organic solvent is 0.2mmol:2mL.

8. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 1, characterized in that: During the reaction, the molar ratio of thiosalicylic acid to benzaldehyde and HI was 0.2:0.5:0.

04.

9. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 1, characterized in that: The organic solvent includes at least one of dichloromethane, chloroform, 1,2-dichloroethane, acetonitrile, ethyl acetate, anhydrous methanol, tetrahydrofuran, and dimethyl sulfoxide.

10. The method for preparing 2-phenylbenzo-1,3-thioxadiene-4-one by HI catalysis according to claim 1, characterized in that: The reaction time is 1h.

Images