Method for synthesizing trifluoromethanesulfonyl chloride

Abstract

The invention discloses a method for synthesizing trifluoromethanesulfonyl chloride, which belongs to the technical field of organic chemical industry, and comprises the following steps: adding a heteropolyacid catalyst into a reaction device, heating, introducing oxygen and trifluoromethyl sulfur chloride, and setting the pressure of a high-pressure reaction container for reaction to prepare trifluoromethanesulfonyl chloride; according to the synthesis method, trifluoromethyl sulfur chloride and oxygen are adopted as raw materials, trifluoromethanesulfonyl chloride is synthesized through a one-step method, and oxygen is simple, easy to obtain and low in price; the heteropolyacid catalyst promotes the reaction process, shortens the reaction time, improves the conversion rate, and can be filtered and recycled after the reaction is completed, so that the catalyst is reutilized, and the production cost is reduced; the synthesis method provided by the invention is clean in reaction, convenient in post-treatment, almost free of three wastes, low in cost, high in yield and suitable for large-scale industrial production, and conforms to the concept of green chemistry.

Description

Technical Field

[0001] The present invention relates to the technical field of organic chemical industry, and in particular to a method for synthesizing trifluoromethanesulfonyl chloride. Background Art

[0002] Trifluoromethanesulfonyl chloride belongs to organic sulfonyl chloride compounds. It is a colorless to pale yellow liquid and is volatile at room temperature. Trifluoromethanesulfonyl chloride is a commonly used reagent in organic synthesis and has a wide range of applications in organic chemistry. It is mainly used to protect hydroxyl functional groups. It reacts with hydroxyl groups to generate the corresponding trifluoromethanesulfonyl protecting group. This protecting group has good stability and can be removed by deprotection reactions under characteristic conditions. In addition, trifluoromethanesulfonyl chloride can also be used as a fluorination reagent to participate in fluorination reactions in organic synthesis.

[0003] In the prior art, the synthesis of trifluoromethanesulfonyl chloride mainly includes the reaction of trifluoromethanesulfonic acid and dichlorothionyl in DMF, fluorination of methanesulfonyl chloride, reaction of trifluoromethanesulfonic acid and phosphorus trichloride, reaction of trifluoromethanesulfinic acid and chlorine, etc. The above methods have complex reaction systems, cumbersome post-treatment, and produce a lot of three wastes, which do not meet the requirements of green chemistry. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a method for synthesizing trifluoromethanesulfonyl chloride to solve the technical problems that the existing synthesis system of trifluoromethanesulfonyl chloride is complex, produces a lot of three wastes, and has high production costs.

[0005] To achieve the above-mentioned purpose, the technical solution adopted in the present application is: to provide a method for synthesizing trifluoromethanesulfonyl chloride, which specifically comprises the following steps: adding a heteropolyacid catalyst into a reaction device and then heating it, then introducing singlet oxygen and trifluoromethylsulfonyl chloride, setting up a pressure reaction in a high-pressure reaction vessel, and obtaining trifluoromethanesulfonyl chloride.

[0006] In one embodiment, The heteropolyacid catalyst includes one of molybdenum heteropolyacid and salts thereof, tungsten heteropolyacid and salts thereof, and cobalt heteropolyacid and salts thereof. Preferably, the heteropolyacid catalyst is molybdenum heteropolyacid and salts thereof.

[0007] In one embodiment, The heating temperature is 90-120°C, preferably, the temperature is 100°C.

[0008] In one embodiment, The molar ratio of oxygen to trifluoromethyl sulfide is 1:2-5, preferably, the molar ratio of oxygen to trifluoromethyl sulfide is 1:3.

[0009] In one embodiment, The rate of introducing oxygen and trifluoromethyl sulfhydryl chloride is 1:2-5, preferably, the rate of introducing is 1:3.

[0010] In one embodiment, The mass ratio of the heteropolyacid catalyst to trifluoromethyl sulfide is 1:4.7-23.5, preferably, the mass ratio of the heteropolyacid catalyst to trifluoromethyl sulfide is 1:14.

[0011] In one embodiment, The reaction time is 2-10 h, preferably, the reaction time is 4 h.

[0012] In one embodiment, The pressure must be maintained throughout the reaction.

[0013] The present application provides a method for synthesizing trifluoromethanesulfonyl chloride. Trifluoromethanesulfonyl chloride and oxygen are used as raw materials to synthesize trifluoromethanesulfonyl chloride in a one-step method. Oxygen is simple, easy to obtain and inexpensive. A heteropolyacid catalyst promotes the reaction process, shortens the reaction time, and improves the conversion rate. The catalyst can be filtered and recovered after the reaction is completed, and the catalyst is reused to reduce the production cost. The synthesis method provided by the present application has a clean reaction, convenient post-treatment, and almost no three wastes are generated, which conforms to the concept of green chemistry, and has low cost and high yield, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 It is a synthetic route for trifluoromethanesulfonyl chloride; Figure 2 The reaction mechanism of trifluoromethanesulfonyl chloride; Figure 3 This is the mass spectrum of trifluoromethanesulfonyl chloride. DETAILED DESCRIPTION

[0016] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clear, the present application is further described in detail. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0017] Example 1 like Figure 1-2As shown, a method for synthesizing trifluoromethanesulfonyl chloride specifically comprises the following steps: adding a heteropolyacid of molybdenum and its salt ((X n+ Mo 12 O 40 ) (8-n)- ) 384 g and then heated to 100 ° C, the mass ratio of molybdenum heteropolyacid and its salt to trifluoromethyl sulfide is 1: 14, and then singlet oxygen and trifluoromethyl sulfide are introduced at a rate of 1: 3, the molar ratio of oxygen to trifluoromethyl sulfide is 1: 3, the pressure of the high-pressure reaction container is the system pressure maintained by the gas at the reaction temperature, and the reaction is carried out for 4 hours to obtain trifluoromethanesulfonyl chloride; trifluoromethanesulfonyl chloride is purified by distillation to obtain 1787 g of trifluoromethanesulfonyl chloride, with a yield of 91.27% and a purity of 92.21%. The structural characterization is as follows Figure 3 As shown; the heteropolyacid catalyst is recovered by filtration.

[0018] Example 2 The difference between this embodiment and embodiment 1 is that the heteropolyacid catalyst is a tungsten heteropolyacid and its salt (X n+ I 12 O 40 ) (8-n)- The remaining operations were the same to obtain trifluoromethanesulfonyl chloride in a yield of 90.8%.

[0019] Example 3 The difference between this embodiment and embodiment 1 is that the heteropoly acid catalyst is a cobalt heteropoly acid and its salt (X n+ Co 12 O 40 ) (8-n)- The remaining operations were the same to obtain trifluoromethanesulfonyl chloride with a yield of 89.69%.

[0020] Example 4 The difference between this example and Example 1 is that the reaction temperature is changed from 100°C to 90°C, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 85.68%.

[0021] Example 5 The difference between this example and Example 1 is that the reaction temperature is changed from 100°C to 120°C, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 84.19%.

[0022] Example 6 The difference between this embodiment and embodiment 1 is that the molar ratio of oxygen to trifluoromethylsulfonyl chloride is changed from 1:3 to 1:2, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 88.22%.

[0023] Example 7 The difference between this embodiment and embodiment 1 is that the molar ratio of trifluoromethylsulfonyl chloride and oxygen is changed from 1:3 to 1:5, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 75.68%.

[0024] Example 8 The difference between this embodiment and embodiment 1 is that the rate of introducing oxygen and trifluoromethylsulfonyl chloride is changed from 1:3 to 1:2, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 88.37%.

[0025] Example 9 The difference between this embodiment and embodiment 1 is that the rate of introducing oxygen and trifluoromethylsulfonyl chloride is changed from 1:3 to 1:5, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 89.91%.

[0026] Example 10 The difference between this embodiment and embodiment 1 is that the mass ratio of molybdenum heteropolyacid and its salt to trifluoromethylsulfonyl chloride is changed to 1:4.7, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 87.39%.

[0027] Embodiment 11 The difference between this embodiment and embodiment 1 is that the mass ratio of molybdenum heteropolyacid and its salt to trifluoromethylsulfonyl chloride is changed to 1:9.4, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 90.12%.

[0028] Example 12 The difference between this embodiment and embodiment 1 is that the mass ratio of molybdenum heteropolyacid and its salt to trifluoromethylsulfonyl chloride is changed to 1:23.5, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 91.05%.

[0029] Embodiment 13 The difference between this embodiment and embodiment 1 is that the amount of molybdenum heteropolyacids and salts thereof added is 298 g, the mass ratio of molybdenum heteropolyacids and salts thereof to trifluoromethylsulfonyl chloride is 1:12, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 80.93%.

[0030] Embodiment 14 The difference between this embodiment and embodiment 1 is that the amount of molybdenum heteropolyacids and salts thereof added is 453 g, the mass ratio of molybdenum heteropolyacids and salts thereof to trifluoromethylsulfonyl chloride is 1:8, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 90.11%.

[0031] Embodiment 15 The difference between this example and Example 1 is that the reaction time is changed from 4 h to 2 h, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 84.19%.

[0032] Example 16 The difference between this embodiment and embodiment 1 is that the reaction time is changed from 4 h to 6 h, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 88.4%.

[0033] Embodiment 17 The difference between this example and Example 1 is that the reaction time is changed from 4 h to 10 h, and the other operations are the same to obtain trifluoromethanesulfonyl chloride with a yield of 75.68%.

[0034] The reaction device is a high-pressure reactor; the preparation of singlet oxygen is a prior art and will not be described in detail here.

[0035] The present application provides a method for synthesizing trifluoromethanesulfonyl chloride, which specifically comprises the following steps: adding a heteropolyacid catalyst into a high-pressure reaction vessel, heating the vessel, introducing oxygen and trifluoromethyl sulfide, setting a pressure reaction in the high-pressure reaction vessel, and preparing trifluoromethanesulfonyl chloride; the synthesis method uses trifluoromethyl sulfide and oxygen as raw materials to synthesize trifluoromethanesulfonyl chloride in a one-step method, and oxygen is simple, easy to obtain, and low in price; the heteropolyacid catalyst promotes the reaction process, shortens the reaction time, and improves the conversion rate, and can be filtered and recovered after the reaction is completed, so that the catalyst is reused and the production cost is reduced; the synthesis method provided by the present application has a clean reaction, convenient post-treatment, almost no three wastes are generated, conforms to the concept of green chemistry, and has low cost and high yield, and is suitable for large-scale industrial production.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0037] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for synthesizing trifluoromethanesulfonyl chloride, characterized in that, The specific steps include: After adding a heteropoly acid catalyst into the reaction device and heating it, singlet oxygen and trifluoromethylsulfonyl chloride are introduced to react to prepare trifluoromethanesulfonyl chloride.

2. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The heteropolyacid catalyst includes one of a molybdenum heteropolyacid and a salt thereof, a tungsten heteropolyacid and a salt thereof, and a cobalt heteropolyacid and a salt thereof.

3. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The heating temperature is 90-120°C.

4. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The molar ratio of oxygen to trifluoromethylsulfonyl chloride is 1:2-5.

5. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The rate of introducing oxygen and trifluoromethylsulfonyl chloride is 1:2-5.

6. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The mass ratio of the heteropolyacid catalyst to trifluoromethyl sulfoxide is 1:4.7-23.

5.

7. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The reaction time is 2-10 h.

8. A method for synthesizing trifluoromethanesulfonyl chloride according to claim 1, characterized in that, The pressure must be maintained throughout the reaction.

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