Preparation method of sulfonyl ketone containing perfluorobutyl

Abstract

The invention discloses a preparation method of perfluorobutanesulfonyl ketone, which comprises the following steps of: heating perfluorobutanesulfonyl fluoride and ethyl acetoacetate to react under normal pressure in the presence of a solvent and alkali, and carrying out three-step reaction to obtain the perfluorobutanesulfonyl ketone. According to the invention, industrial products perfluorobutanesulfonyl fluoride and ethyl acetoacetate are selected as raw materials, the method has the advantages of simple operation, cheap and easily available reagents, environmental protection and the like, the total yield of the three-step reaction can reach 85%, and the method is beneficial to industrial production.

Description

Technical Field

[0001] The invention belongs to the technical field of fine chemical synthesis, and specifically relates to a preparation method of a perfluorobutyl sulfonyl ketone. Background Art

[0002] Perfluorobutylsulfonyl ketone is a new ketone compound, and there are few research reports related to it. According to our research, it has the following advantages compared with other ketones:

[0003] 1. Can be used as a high-quality surfactant precursor;

[0004] 2. It contains both hydrophobic perfluoroalkyl groups and hydrophilic carbonyl groups, and is a natural surfactant with potential application value.

[0005] Due to the unique advantages of perfluorobutyl sulfonyl ketone, it is urgent to develop a method for synthesizing perfluorobutyl sulfonyl ketone. Summary of the invention

[0006] The object of the present invention is to provide a method for preparing a perfluorobutyl sulfonyl ketone in view of the above-mentioned problems.

[0007] The present invention provides a method for preparing a perfluorobutyl sulfonyl ketone, comprising the following steps:

[0008] Under normal pressure, perfluorobutylsulfonyl fluoride and ethyl acetoacetate are heated to react in the presence of a solvent and a base, and then decarboxylation and acidification are performed to obtain 1-((perfluorobutyl)sulfonyl)propan-2-one in a total of three steps. The reaction equation is shown in Formula 1:

[0009]

[0010] In some embodiments: the molar ratio of perfluorobutylsulfonyl fluoride to ethyl acetoacetate in Formula 1A is not higher than 1:1, preferably, the molar ratio of perfluorobutylsulfonyl fluoride to ethyl acetoacetate is 1:(1.1-2), and the usage ratio of ethyl acetoacetate to solvent is 1 mmol:(1-4 mL), preferably, the usage ratio of ethyl acetoacetate to solvent is 1 mmol:(1-1.5) mL.

[0011] In some embodiments: the base in Formula 1A is one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, n-butyl lithium, sodium hydride, sodium amide or cesium carbonate, and the molar ratio of the base to perfluorobutylsulfonyl fluoride is not higher than 1:0.1, preferably, the molar ratio of the base to perfluorobutylsulfonyl fluoride is 1:(0.1~22).

[0012] In some embodiments: the solvent in Formula 1A is one of ethyl acetate, acetonitrile, dichloromethane, chloroform, chlorobenzene, toluene, benzene, tetrahydrofuran or 1,2-dichloroethane.

[0013] In some embodiments: the atmosphere of the heating reaction in Formula 1A is a protective atmosphere or an air atmosphere. Preferably, the atmosphere of the heating reaction is an air atmosphere, the reaction temperature is 40 to 150° C., and the reaction time is 8 h to 48 h.

[0014] In some embodiments: the intermediate A in Formula 1A is obtained by separation and purification, and the separation and purification steps are: removing the solvent by reduced pressure distillation, washing with water, extracting with tert-methyl ether, and then concentrating and separating by column chromatography to obtain the intermediate A.

[0015] In some embodiments: in Formula 1B, the ratio of the intermediate A to the solvent is 1 mmol: (1-3) mL. Preferably, the ratio of the intermediate A to the solvent is 1 mmol: (1-1.5) mL.

[0016] In some embodiments: the base in Formula 1B is sodium hydroxide or potassium hydroxide, and the molar ratio of the base to the intermediate A is not higher than 1:1. Preferably, the molar ratio of the base to the intermediate A is 1:(1-2).

[0017] In some embodiments: the solvent in Formula 1B is one of ethyl acetate, acetonitrile, dichloromethane, chloroform, chlorobenzene, toluene, benzene, tetrahydrofuran or 1,2-dichloroethane.

[0018] In some embodiments: the atmosphere of the heating reaction in Formula 1B is a protective atmosphere or an air atmosphere. Preferably, the atmosphere of the heating reaction is an air atmosphere. The reaction temperature in Formula 1B is 40 to 150° C., and the reaction time is 8 h to 48 h.

[0019] In some embodiments, the inorganic acid in Formula 1B is dilute sulfuric acid, and the concentration of the dilute sulfuric acid is 5% to 60%. Preferably, the concentration of the dilute sulfuric acid is 10% to 60%.

[0020] In some embodiments: the perfluorobutyl sulfonyl ketone in Formula 1B is obtained by separation and purification, and the separation and purification steps are: removing the solvent by distillation under reduced pressure, washing with water, extracting with tert-methyl ether, and then concentrating and separating by column chromatography to obtain the product 1-((perfluorobutyl)sulfonyl)propan-2-one.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The invention uses industrial raw materials perfluorobutylsulfonyl fluoride and ethyl acetoacetate as raw materials, heats the reaction under the condition of a solvent and a base, and heats the reaction under the condition of a solvent and a base to prepare the perfluorobutylsulfonyl ketone through three steps of acylation, decarboxylation and acidification. The invention has the advantages of no need for a catalyst, cheap and easy to obtain raw materials, simple operation, green and environmental protection, etc., and is conducive to industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 FIG. 1 is a liquid chromatogram of perfluorobutylsulfonyl ketone in one embodiment of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0025] Embodiment 1:

[0026] A method for preparing a perfluorobutylsulfonyl ketone comprises the following steps:

[0027] S1. Under normal pressure, perfluorobutylsulfonyl fluoride and ethyl acetoacetate are heated to react in the presence of solvent ethyl acetate and base sodium hydroxide. The molar ratio of perfluorobutylsulfonyl fluoride to ethyl acetoacetate is 1:1.2, the molar ratio of the base to perfluorobutylsulfonyl fluoride is 1:1, the amount ratio of ethyl acetoacetate to the solvent is 1 mol / L, the atmosphere of the heating reaction is air atmosphere, the heating reaction temperature is 100°C; the heating reaction time is 8h. After the reaction is completed, the solvent must be removed by reduced pressure distillation, washed with water, extracted with tert-methyl ether, and then concentrated by column chromatography to obtain intermediate A.

[0028] S2. Under normal pressure, the intermediate A is heated and decarboxylated in the presence of sodium hydroxide and ethyl acetate, and then the inorganic acid dilute sulfuric acid is added for acidification to obtain 1-((perfluorobutyl)sulfonyl)propan-2-one. The concentration of the dilute sulfuric acid is 60%, the dosage ratio of the intermediate A to the solvent is 1 mol / L, the molar ratio of the base to the intermediate A is 1:1, the atmosphere of the heating reaction is air atmosphere, the heating reaction temperature is 100°C, and the thermal reaction time is 8h. After the reaction is completed, the solvent must be removed by reduced pressure distillation, washed with water, extracted with tertiary methyl ether, and then concentrated by column chromatography to obtain the product 1-((perfluorobutyl)sulfonyl)propan-2-one. After 1-((perfluorobutyl)sulfonyl)propan-2-one is purified, tertiary methyl ether is used as the solvent. Its liquid chromatogram is as shown below. Figure 1 , the purity can reach 97%.

[0029] The invention uses industrial raw materials perfluorobutylsulfonyl fluoride and ethyl acetoacetate as raw materials, heats the reaction under the condition of a solvent and a base, and heats the reaction under the condition of a solvent and a base to prepare the perfluorobutylsulfonyl ketone through three steps of acylation, decarboxylation and acidification. The invention has the advantages of no need for a catalyst, cheap and easy to obtain raw materials, simple operation, green and environmental protection, etc., and is conducive to industrial production.

[0030] Finally, it should be noted that: technicians in this industry should understand that the present invention is not limited to the above-mentioned implementation cases. The above-mentioned embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for preparing a perfluorobutylsulfonyl ketone, characterized in that: The following steps are involved: Under normal pressure, perfluorobutylsulfonyl fluoride and ethyl acetoacetate are heated to react in the presence of a solvent and a base, and then decarboxylation and acidification are performed to obtain 1-((perfluorobutyl)sulfonyl)propan-2-one in a total of three steps. The reaction equation is shown in Formula 1:

2. The preparation method according to claim 1, characterized in that: The molar ratio of perfluorobutylsulfonyl fluoride to ethyl acetoacetate in Formula 1A is not higher than 1:

1. Preferably, the molar ratio of perfluorobutylsulfonyl fluoride to ethyl acetoacetate is 1:

1. (1.1-2), the usage ratio of ethyl acetoacetate to the solvent is 1 mmol:(1-4 mL), preferably, the usage ratio of ethyl acetoacetate to the solvent is 1 mmol:(1-1.5) mL.

3. The preparation method according to claim 1, characterized in that: The base in Formula 1A is one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, n-butyl lithium, sodium hydride, sodium amide or cesium carbonate, and the molar ratio of the base to perfluorobutylsulfonyl fluoride is not higher than 1:0.

1. Preferably, the molar ratio of the base to perfluorobutylsulfonyl fluoride is 1:(0.1-22).

4. The preparation method according to claim 1, characterized in that: The solvent in Formula 1A is one of ethyl acetate, acetonitrile, dichloromethane, chloroform, chlorobenzene, toluene, benzene, tetrahydrofuran or 1,2-dichloroethane.

5. The preparation method according to claim 1, characterized in that: The atmosphere of the heating reaction in Formula 1A is a protective atmosphere or an air atmosphere. Preferably, the atmosphere of the heating reaction is an air atmosphere. The reaction temperature is 40 to 150° C., and the reaction time is 8 to 48 hours.

6. The preparation method according to claims 1 to 5, characterized in that: The intermediate A in Formula 1A is obtained by separation and purification, wherein the separation and purification steps are: removing the solvent by distillation under reduced pressure, washing with water, extracting with tert-methyl ether, and then concentrating and separating by column chromatography to obtain the intermediate A.

7. The preparation method according to claim 1, characterized in that: In Formula 1B, the ratio of the intermediate A to the solvent is 1 mmol: (1-3) mL. Preferably, the ratio of the intermediate A to the solvent is 1 mmol: (1-1.5) mL.

8. The preparation method according to claim 1, characterized in that: In Formula 1B, the base is sodium hydroxide or potassium hydroxide, and the molar ratio of the base to the intermediate A is not higher than 1:

1. Preferably, the molar ratio of the base to the intermediate A is 1: (1～2)。 9. The preparation method according to claim 1, characterized in that: The solvent in Formula 1B is one of ethyl acetate, acetonitrile, dichloromethane, chloroform, chlorobenzene, toluene, benzene, tetrahydrofuran or 1,2-dichloroethane.

10. The preparation method according to claim 1, characterized in that: The atmosphere of the heating reaction in Formula 1B is a protective atmosphere or an air atmosphere. Preferably, the atmosphere of the heating reaction is an air atmosphere. The reaction temperature in Formula 1B is 40 to 150° C., and the reaction time is 8 h to 48 h.

11. The preparation method according to claim 1, characterized in that: The inorganic acid described in Formula 1B is dilute sulfuric acid, and the concentration of the dilute sulfuric acid is 5% to 60%. Preferably, the concentration of the dilute sulfuric acid is 10% to 60%.

12. The preparation method according to claims 7 to 11, characterized in that: The perfluorobutyl sulfonyl ketone in formula 1B is obtained by separation and purification, and the separation and purification steps are: removing the solvent by reduced pressure distillation, washing with water, extracting with tertiary methyl ether, and then concentrating and separating by column chromatography to obtain the product 1-((perfluorobutyl)sulfonyl)propan-2-one.

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