A method for synthesizing methylsulfonyl fluoride and calcium chloride

Abstract

The application discloses a method for synthesizing methylsulfonyl fluoride and calcium chloride, and belongs to the technical field of chemical synthesis. The method comprises the following steps: mixing calcium fluoride with a non-aqueous solvent to obtain a mixed solution, adding methylsulfonyl chloride into the mixed solution, performing a heat preservation reaction after the addition of the methylsulfonyl chloride is completed, and separating methylsulfonyl fluoride and calcium chloride after the reaction is completed. The reaction process of the method avoids hydrolysis, has few side reactions, completely omits a distillation step with high energy consumption, and can realize resource utilization of fluorite, a three-waste byproduct in industry, so that the purposes of energy saving and consumption reduction, process simplification and green environmental protection are achieved.

Description

Technical Field

[0001] This invention belongs to the field of fine chemical and pharmaceutical synthesis technology, specifically relating to a method for synthesizing methanesulfonyl fluoride and calcium chloride. Background Technology

[0002] In existing production processes, the reaction of solid reactants calcium fluoride with methanesulfonyl chloride to prepare solid products methanesulfonyl fluoride and calcium chloride (reaction formula: calcium fluoride + methanesulfonyl chloride → methanesulfonyl fluoride + calcium chloride) generally uses water as the reaction medium or as the mother liquor for post-treatment washing. However, the applicant's in-depth research has revealed significant drawbacks to using water as a medium: 1. Hydrolysis Side Reactions: In an aqueous environment, especially at the reaction temperature, the sulfonyl group in the reactant methanesulfonyl chloride and the target product methanesulfonyl fluoride is prone to hydrolysis and other side reactions. These side reactions not only consume valuable raw materials and generate impurities that are difficult to separate, but also severely limit the theoretical yield of the target product. Currently, the industry average yield of this traditional method is approximately 96.4%.

[0003] 2. High energy consumption in separation and purification: After the reaction, in order to obtain a high-purity solid product from the aqueous phase and recover water resources, a high-energy-consuming distillation operation must be used to remove water. This process involves large equipment investment, high energy costs, and prolongs the production cycle.

[0004] 3. Limited sources of calcium fluoride raw materials: Existing processes mostly use high-purity commercial calcium fluoride, while a large amount of industrial waste containing calcium fluoride has not been effectively utilized, resulting in resource waste and increased treatment costs.

[0005] Therefore, developing a new method that can effectively avoid hydrolysis side reactions, further improve yield, and fundamentally simplify the separation process and reduce production costs has significant industrial application value. Summary of the Invention

[0006] The purpose of this invention is to provide a method for synthesizing methanesulfonyl fluoride and calcium chloride, which uses non-aqueous solvents to suppress side reactions, significantly improve product yield, and simplify subsequent separation and purification processes.

[0007] The technical solution of the present invention: A method for synthesizing methanesulfonyl fluoride and calcium chloride includes the following steps: mixing calcium fluoride with a non-aqueous solvent to obtain a mixture, then adding methanesulfonyl chloride to the mixture, and after adding methanesulfonyl chloride, carrying out a heat-preserving reaction, and after the reaction is completed, cooling and separating to obtain methanesulfonyl fluoride and calcium chloride.

[0008] Preferably, the non-aqueous solvent is methanesulfonyl fluoride, and the mass ratio of calcium fluoride to the non-aqueous solvent is 1:12.1-12.3; the molar ratio of calcium fluoride to methanesulfonyl chloride is 1.00-1.10:2.

[0009] Preferably, the mixture is stirred while being slowly added to the mixture.

[0010] Preferably, the methanesulfonyl chloride is added by dripping, and the dripping time is controlled within 1-3 hours.

[0011] Preferably, the dripping time is 2 hours.

[0012] Preferably, the temperature at which the reactant methanesulfonyl chloride is added to the mixture is 50℃±2℃.

[0013] Preferably, the temperature of the heat preservation reaction is 50℃±2℃, and the heat preservation reaction time is 4 hours.

[0014] Preferably, the purity of the non-aqueous solvent is greater than 98%.

[0015] Preferably, after the reaction is complete, the temperature is lowered to room temperature, and the separation method is centrifugation or pressure filtration.

[0016] Preferably, the methylsulfonyl fluoride obtained by cooling separation is directly recycled to the next batch for use as a non-aqueous solvent.

[0017] Preferably, the room temperature is 4-38℃.

[0018] 1. Selection of non-aqueous solvent: High-purity methanesulfonyl fluoride, as a non-aqueous solution, will not trigger the hydrolysis of methanesulfonyl chloride.

[0019] 2. Initial Feeding and Mixing: Add all the measured solid reactant calcium fluoride to the non-aqueous solution, start stirring and heat to 50±2℃ to form a calcium fluoride suspension mixture, which is beneficial for the reaction. The calcium fluoride can be a byproduct of industrial waste that has undergone simple pretreatment to replace high-purity commercial products.

[0020] 3. Controlled Feeding Reaction: Methylsulfonyl chloride was slowly and dropwise added to the calcium fluoride suspension mixture at 50±2℃ with stirring. This slow addition process is crucial, as it effectively controls the reaction rate, avoids side reactions caused by excessively high local concentrations or instantaneous exothermic reactions, and further suppresses the risk of hydrolysis. After all materials have been added, the reaction was maintained at 50±2℃ for 4 hours to ensure complete reaction and obtain a reaction slurry rich in the solid products calcium chloride and methylsulfonyl fluoride solution.

[0021] 4. Separation and Recycling: After the reaction is complete, the resulting reaction slurry is cooled to room temperature and then separated by centrifugation or pressure filtration to directly obtain the products methanesulfonyl fluoride and calcium chloride. The product methanesulfonyl fluoride can be directly recycled for use in the next batch of reaction as a non-aqueous solvent, achieving a closed-loop recycling of materials.

[0022] The beneficial effects of this invention are: 1. This invention completely avoids hydrolysis and significantly improves yield: By using non-aqueous methanesulfonyl fluoride to replace water, the hydrolysis side reaction pathway is fundamentally eliminated. Combined with the optimized process of slowly adding methanesulfonyl chloride at 50±2℃, the reaction becomes milder and more controllable, thereby steadily increasing the product yield from the traditional 96.4% to over 98.8%, resulting in significant economic benefits.

[0023] 2. This invention revolutionizes the separation process with a significant reduction in energy consumption: Since the mother liquor system itself is water-free and can be directly recycled, post-treatment only requires simple filtration to separate the solid product, completely eliminating the energy-intensive distillation step necessary in traditional processes. This greatly reduces steam and electricity consumption, and decreases equipment investment and operating costs.

[0024] 3. Green and environmentally friendly: It achieves near-zero emission recycling of the valuable component product, methanesulfonyl fluoride, which is in line with the concepts of green chemistry and sustainable development.

[0025] 4. Improved product quality: The reduction of side reactions directly reduces the impurity content in the product, improving the purity and quality consistency of the final product.

[0026] 5. Resource utilization: This invention can directly use calcium fluoride, a byproduct of industrial waste, as a raw material, realizing the resource utilization of waste, greatly reducing raw material costs, and conforming to the concepts of green chemistry and circular economy. Detailed Implementation

[0027] Example 1:

[0028] 65 g of calcium fluoride (97% purity) was added to a 2 L four-necked flask equipped with a stirrer, thermometer, dropping funnel, and reflux condenser. Stirring was started, and 800 g of methanesulfonyl fluoride (99% purity) was added. The mixture in the four-necked flask was heated to 50 °C and maintained. 178 g of methanesulfonyl chloride (99% purity) was weighed and transferred to the dropping funnel. At 50 °C, the methanesulfonyl chloride solution was slowly and evenly added dropwise to the reaction flask over 2 hours. After the addition was complete, the reaction was maintained at 50 °C for another 4 hours (total reaction time approximately 6 hours, including the addition time). After the reaction was complete, the slurry was cooled to 20 °C, filtered by pressure, and solid calcium chloride and filtrate methanesulfonyl fluoride were obtained. The yield and purity of methanesulfonyl fluoride were determined by HPLC. HPLC analysis showed that the total yield of methanesulfonyl fluoride, calculated as methanesulfonyl chloride, was 98.89%, and the purity of methanesulfonyl fluoride was 98.90%. Example 2:

[0029] Using the process conditions of Example 1, five batches of reactions were carried out consecutively. The filtrate obtained from the previous batch was used as the mother liquor for each batch, without adding fresh non-aqueous solvent. The specific results are as follows: Operating procedure: After each batch of reaction is completed, the reaction slurry is cooled to 20°C, centrifuged to obtain solid product, and the filtrate is used directly as the non-aqueous solvent for the next batch without any addition or treatment.

[0030] Results analysis: After five consecutive batches of recycling, the yield remained stable at over 98.86% and the purity remained above 98.8%, indicating that the mother liquor has good recycling performance and no significant decrease in yield due to impurity accumulation occurred. These results fully verify the feasibility and stability of the method of this invention in industrial continuous production. Example 3:

[0031] 65 g of calcium fluoride (97% purity) was added to a 2 L four-necked flask equipped with a stirrer, thermometer, dropping funnel, and reflux condenser. Stirring was started, and 789 g of methanesulfonyl fluoride (99% purity) was added. The mixture in the four-necked flask was heated to 52 °C and maintained. 170 g of methanesulfonyl chloride (99% purity) was weighed and transferred to a dropping funnel. At 52 °C, the methanesulfonyl chloride solution was slowly and evenly added dropwise to the reaction flask over 3 hours. After the addition was complete, the reaction was maintained at 52 °C for another 4 hours. After the reaction was complete, the slurry was cooled to 25 °C, centrifuged, and solid calcium chloride and filtrate methanesulfonyl fluoride were obtained. The yield and purity of methanesulfonyl fluoride were determined by HPLC. HPLC analysis showed that the total yield of methanesulfonyl fluoride, calculated based on methanesulfonyl chloride, was 98.90%, and the purity of methanesulfonyl fluoride was 98.80%. Example 4:

[0032] 65 g of calcium fluoride (97% purity) was added to a 2 L four-necked flask equipped with a stirrer, thermometer, dropping funnel, and reflux condenser. Stirring was started, and 795 g of methanesulfonyl fluoride (99% purity) was added. The mixture in the four-necked flask was heated to 48 °C and maintained. 187 g of methanesulfonyl chloride (99% purity) was weighed and transferred to the dropping funnel. At 48 °C, the methanesulfonyl chloride solution was slowly and evenly added dropwise to the reaction flask over 1 hour. After the addition was complete, the reaction was maintained at 48 °C for 4 hours. After the reaction was complete, the slurry was cooled to 35 °C, centrifuged, and solid calcium chloride and filtrate methanesulfonyl fluoride were obtained. The yield and purity of methanesulfonyl fluoride were determined by HPLC. HPLC analysis showed that the total yield of methanesulfonyl fluoride, calculated based on methanesulfonyl chloride, was 98.80%, and the purity of methanesulfonyl fluoride was 98.50%.

[0033] Comparative Example 1: 65g of 97% pure calcium fluoride was added to a reaction flask using 800g of deionized water as a solvent. After heating to 50℃, 178g of 99% pure methanesulfonyl chloride solution was slowly and evenly added dropwise over 2 hours. The reaction was carried out at 50℃ for 4 hours. The slurry after the reaction was distilled to remove most of the water, and the remaining wet material was dried. The yield and purity of the distillate fraction of methanesulfonyl fluoride were determined by HPLC. The final product, after analysis and calculation, showed a yield of 96.45% and a purity of 98.89% for methanesulfonyl fluoride.

[0034] The method of the present invention (Example 1), after precisely controlling the reaction temperature (50°C) and adopting a slow dropwise addition of methanesulfonyl chloride, significantly improves the yield compared with the traditional method (Comparative Example 1), while the product purity is not much different, but the energy-intensive distillation step is eliminated.

[0035] Comparative Example 2: 65 g of calcium fluoride (97% purity) was added to a 2 L four-necked flask equipped with a stirrer, thermometer, dropping funnel, and reflux condenser. Stirring was started, and 800 g of methanesulfonyl fluoride (99% purity) was added. The system was heated to 50 °C and maintained. 178 g of methanesulfonyl chloride (99% purity) was weighed. The methanesulfonyl chloride solution was added to the reaction flask in one go at 50 °C. After the addition was complete, the reaction was maintained at 50 °C for another 4 hours (total reaction time approximately 6 hours, including the addition time). After the reaction was complete, the slurry was cooled to 20 °C. The yield and purity of methanesulfonyl fluoride were determined by HPLC. The mixture was then filtered to obtain solid calcium chloride and filtrate methanesulfonyl fluoride. HPLC analysis showed that the total yield, based on methanesulfonyl chloride, was 98.82%, and the purity of methanesulfonyl fluoride was 97.91%.

[0036] The method of the present invention (Example 1), after precisely controlling the reaction temperature (50°C) and using a slow dropwise addition of methanesulfonyl chloride, significantly improves the yield and product purity compared to Comparative Example 2, which adds the methanesulfonyl chloride solution to the reaction flask all at once.

[0037] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for synthesizing methanesulfonyl fluoride and calcium chloride, characterized in that, Includes the following steps: Calcium fluoride is mixed with a non-aqueous solvent to obtain a mixture. Methylsulfonyl chloride is then added to the mixture. After the addition of methylsulfonyl chloride, the mixture is kept at a constant temperature for reaction. After the reaction is complete, the mixture is cooled and separated to obtain methylsulfonyl fluoride and calcium chloride.

2. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, The non-aqueous solvent is methanesulfonyl fluoride, and the mass ratio of calcium fluoride to the non-aqueous solvent is 1:12.1-12.3; the molar ratio of calcium fluoride to methanesulfonyl chloride is 1.00-1.10:

2.

3. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, Stirring is performed while slowly adding methanesulfonyl chloride to the mixture.

4. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, The methanesulfonyl chloride is added dropwise over a period of 1-3 hours.

5. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 4, characterized in that, The dripping time is 2 hours.

6. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 4, characterized in that, The temperature at which the reactant methanesulfonyl chloride is added to the mixture is 50℃±2℃.

7. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, The temperature for the heat preservation reaction was 50℃±2℃, and the heat preservation reaction time was 4 hours.

8. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, The purity of the non-aqueous solvent is greater than 98%.

9. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, After the reaction is complete, the temperature is lowered to room temperature, and the separation is carried out by centrifugation or pressure filtration.

10. The method for synthesizing methanesulfonyl fluoride and calcium chloride according to claim 1, characterized in that, The methylsulfonyl fluoride obtained by cooling separation is directly recycled to the next batch for use as a non-aqueous solvent.

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