Synthetic method of perfluorobutyl sulfonyl fluoride

Abstract

The invention relates to the technical field of organic synthesis, in particular to a synthetic method of perfluorobutanesulfonyl fluoride. The synthesis method comprises the following steps: S1, mixing water, a phase transfer catalyst, sodium pyrosulfite and acetonitrile to obtain a mixture, and adding perfluorobutyl iodide into the mixture for reaction to obtain a solid; s2, dissolving the solid with a hydrochloric acid solution, and introducing chlorine for reaction to obtain perfluorobutyl sulfonyl chloride; and S3, the perfluorobutyl sulfonyl chloride, potassium fluoride and water are subjected to a reaction, and the perfluorobutyl sulfonyl fluoride is obtained. According to the synthetic method, perfluorobutyl iodide is taken as a raw material, and perfluorobutyl sulfonyl fluoride is synthesized through an imidization deiodination reaction, a chlorination reaction and a fluorination reaction in sequence. The synthesis method is simple and easy to operate, the tail gas treatment process is reduced, and the raw material utilization efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of organic synthesis, and in particular to a method for synthesizing perfluorobutylsulfonyl fluoride. Background Art

[0002] Perfluorobutyl sulfonyl fluoride is mainly used in the synthesis of fluorocarbon surfactants, fluorinated pesticides, dyes, polycarbonate processing dispersants, etc. It is the best flame retardant for polycarbonate because of its thermal stability and low friction coefficient. At the same time, perfluorobutyl sulfonyl fluoride also has good electrical insulation properties and can be used as an insulating material for electronic components. As a highly stable chemical reagent, perfluorobutyl sulfonyl fluoride can be used in organic synthesis reactions, such as fluorination reactions, sulfurization reactions, etc.

[0003] At present, the most commonly used method for preparing perfluorobutylsulfonyl fluoride is the Simon electrolytic fluorination method, as shown in the Chinese invention patent application number 201180006487, using butanesulfonyl chloride and anhydrous hydrogen fluoride as raw materials, hydrogen is produced at the cathode through electrolysis, and perfluorobutylsulfonyl fluoride is generated at the anode. This method has the following disadvantages: 1. The hydrogen fluoride used needs to be cooled at low temperature before electrolysis and is highly corrosive; 2. Since butylsulfonyl fluoride is first generated in the reaction process, and then the final product, perfluorobutylsulfonyl fluoride, is obtained by further fluorination, the solubility and electrolysis efficiency of butylsulfonyl fluoride in anhydrous hydrogen fluoride are low; 3. The hydrogen produced by the reaction carries a certain amount of hydrogen fluoride, and the tail gas treatment is complicated. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for synthesizing non-electrolytic perfluorobutylsulfonyl fluoride. In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for synthesizing perfluorobutylsulfonyl fluoride, comprising the following steps: S1: firstly mixing water, a phase transfer catalyst, sodium pyrosulfite and acetonitrile to obtain a mixture, and adding perfluorobutyl iodide to the mixture to react and obtain a solid; S2: dissolving the solid in a hydrochloric acid solution and then introducing chlorine gas to react to obtain perfluorobutanesulfonyl chloride; S3: reacting the perfluorobutylsulfonyl chloride, potassium fluoride and water to obtain perfluorobutylsulfonyl fluoride.

[0005] The beneficial effect of the present invention is that the synthesis method of the present invention uses perfluorobutyl iodide as a raw material to synthesize perfluorobutylsulfonyl fluoride through imidization deiodination reaction, chlorination reaction and fluorination reaction in sequence. The synthesis method is simple, easy to operate, reduces the tail gas treatment process, and improves the utilization efficiency of raw materials. DETAILED DESCRIPTION

[0006] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes.

[0007] A method for synthesizing perfluorobutylsulfonyl fluoride comprises the following steps: S1: firstly mixing water, a phase transfer catalyst, sodium pyrosulfite and acetonitrile to obtain a mixture, and adding perfluorobutyl iodide to the mixture to react and obtain a solid; S2: dissolving the solid in hydrochloric acid solution and then introducing chlorine gas to react to obtain perfluorobutanesulfonyl chloride; S3: reacting perfluorobutylsulfonyl chloride, potassium fluoride and water to obtain perfluorobutylsulfonyl fluoride.

[0008] From the above description, it can be seen that the beneficial effect of the present invention is that: the synthesis method of the present invention uses perfluorobutyl iodide as a raw material to generate an intermediate product perfluorobutyl sulfonyl chloride through an imidization deiodination reaction and a chlorination reaction, and finally prepares perfluorobutyl sulfonyl fluoride through a simple fluorination reaction. The synthesis method does not prepare perfluorobutyl sulfonyl fluoride by electrolysis, reduces the tail gas treatment process, improves the raw material utilization efficiency, and avoids the requirement of low-temperature corrosion-resistant equipment for hydrogen fluoride.

[0009] Furthermore, the mass of the phase transfer catalyst in S1 is 0.8-1.2 wt % of the mass of perfluorobutyl iodide.

[0010] From the above description, it can be seen that if the amount of phase transfer catalyst added is too little, the reaction efficiency is low, and if the amount of phase transfer catalyst added is too much, it will lead to increased side reactions and reduced yield.

[0011] Furthermore, the mass ratio of perfluorobutyl iodide to sodium pyrosulfite in S1 is 0.8~1.2:1.

[0012] Furthermore, the mass ratio of water to acetonitrile in S1 is 1:2.8~3.2.

[0013] From the above description, it can be seen that the acetonitrile content should not be too high, as too high an acetonitrile content will lead to a significant increase in the reaction time.

[0014] Furthermore, the mass ratio of perfluorobutyl iodide to water in S1 is 1:2.8~3.3.

[0015] From the above description, it can be seen that the water content should not be too high, as too much water content will reduce the reaction rate and increase the reaction time.

[0016] Furthermore, the phase transfer catalyst is hexadecyltrimethylammonium bromide or polyethylene glycol.

[0017] Furthermore, the mixture in S1 is heated to 50-60° C. and then perfluorobutyl iodide is added to react for 5.5-6.5 hours to obtain a solid.

[0018] From the above description, it can be seen that heating up first and then adding perfluorobutyl iodide can activate the substrate, accelerate the reaction progress, and better control the reaction temperature.

[0019] Furthermore, the mass percentage of the hydrochloric acid solution in S2 is 4-6%.

[0020] From the above description, it can be seen that the amount of hydrochloric acid solution added is sufficient to completely dissolve the solid.

[0021] Furthermore, S2 is specifically as follows: dissolving the solid in hydrochloric acid solution, cooling the mixture to 10-15° C., and introducing chlorine gas to react until the reaction solution turns black, thereby obtaining perfluorobutylsulfonyl fluoride.

[0022] Furthermore, the mass ratio of perfluorobutanesulfonyl chloride, potassium fluoride and water in S3 is 1:3.5~4.5:2.

[0023] Furthermore, the reaction conditions of S3 are 50-60° C. for 7.5-8.5 h.

[0024] From the above description, it can be seen that the reaction time should not be too long, as the reaction time will cause white solid to precipitate, which is difficult to clean up.

[0025] Embodiment 1 of the present invention is: a method for synthesizing perfluorobutylsulfonyl fluoride, the steps are as follows: S1: Add 0.700 g of water, 2.14 g of hexadecyltrimethylammonium bromide, 250 g of sodium metabisulfite and 2100 g of acetonitrile to a reaction kettle and mix to obtain a mixture. After heating the reaction kettle to 55°C, slowly add 214 g of perfluorobutyl iodide (addition takes 3 hours), and continue the reaction for 6 hours to obtain a solid. S2: The solid was completely dissolved in a 5% by mass hydrochloric acid solution, then the temperature was lowered to 13°C, chlorine gas was introduced to react until the reaction liquid turned black, and the liquid was separated to obtain perfluorobutylsulfonyl fluoride solid; S3: 143.34 g of perfluorobutylsulfonyl fluoride, 4 g of potassium fluoride and 2 g of water are reacted at 55° C. for 8 h, and the resulting lower layer liquid is perfluorobutylsulfonyl chloride.

[0026] Embodiment 2 of the present invention is: The only difference between Example 2 and Example 1 is that when the reaction time is prolonged, a large amount of white solid is precipitated.

[0027] Embodiment 3 of the present invention is: The only difference between Example 3 and Example 1 is that the addition of perfluorobutyl iodide is completed within 2 hours.

[0028] The yields in Examples 1 to 3 were calculated, and the calculation results are shown in Tables 1 and 2.

[0029] Table 1

[0030] Table 2

[0031] As shown in Table 1, the yield of perfluorobutyl iodide as a raw material can reach 74.8% for perfluorobutyl sulfonyl chloride and 82.867% for perfluorobutyl sulfonyl fluoride, which are relatively high. By comparing the data of Example 2 and Example 3, it can be seen that the yield can be increased by regulating the addition speed of perfluorobutyl iodide. If the addition speed of perfluorobutyl iodide is too fast, airflow will be generated at the nozzle, and if it is too slow, sodium pyrosulfite will decompose.

[0032] Embodiment 4 of the present invention is: a method for synthesizing perfluorobutylsulfonyl fluoride, the steps are as follows: S1: 599.2 g of water, 1.71 g of polyethylene glycol, 267.5 g of sodium metabisulfite and 1677.76 g of acetonitrile were added to a reaction kettle and mixed to obtain a mixture. After the reaction kettle was heated to 50° C., 214 g of perfluorobutyl iodide was slowly added and the reaction was continued for 5.5 h to obtain a solid; S2: The solid is completely dissolved in a 4% by mass hydrochloric acid solution, then cooled to 10°C, chlorine gas is introduced to react until the reaction liquid turns black, and the liquid is separated to obtain perfluorobutylsulfonyl fluoride solid; S3: 1 g of perfluorobutylsulfonyl fluoride, 3.5 g of potassium fluoride and 2 g of water are reacted at 50°C for 7.5 h, and the resulting lower layer liquid is perfluorobutylsulfonyl chloride.

[0033] Embodiment 5 of the present invention is: a method for synthesizing perfluorobutylsulfonyl fluoride, the steps are as follows: S1: 706.2 g of water, 2.57 g of polyethylene glycol, 178.33 g of sodium metabisulfite and 2259.84 g of acetonitrile were added to a reaction kettle and mixed to obtain a mixture. After the temperature of the reaction kettle was raised to 60° C., 214 g of perfluorobutyl iodide was slowly added and the reaction was continued for 6.5 h to obtain a solid; S2: The solid is completely dissolved in a 6% by mass hydrochloric acid solution, then cooled to 15°C, chlorine gas is introduced to react until the reaction liquid turns black, and the liquid is separated to obtain perfluorobutylsulfonyl fluoride solid; S3: 1 g of perfluorobutylsulfonyl fluoride, 4.5 g of potassium fluoride and 2 g of water are reacted at 60°C for 7.5-8.5 hours, and the resulting lower layer liquid is perfluorobutylsulfonyl chloride.

[0034] In summary, the synthesis method of perfluorobutylsulfonyl fluoride provided by the present invention has the following advantages: 1. The synthesis method is simple to operate, easy to repeat and has a high yield.

[0035] 2. No need for electrolysis, reducing the tail gas treatment process; 3. The reaction process is less corrosive, the temperature requirement is not high, and the equipment requirements are relatively low.

[0036] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the specification of the present invention, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for synthesizing perfluorobutylsulfonyl fluoride, characterized in that: The following steps are involved: S1: firstly mixing water, a phase transfer catalyst, sodium pyrosulfite and acetonitrile to obtain a mixture, and adding perfluorobutyl iodide to the mixture to react and obtain a solid; S2: dissolving the solid in a hydrochloric acid solution and then introducing chlorine gas to react to obtain perfluorobutanesulfonyl chloride; S3: reacting the perfluorobutylsulfonyl chloride, potassium fluoride and water to obtain perfluorobutylsulfonyl fluoride.

2. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mass of the phase transfer catalyst in S1 is 0.8-1.2 wt % of the mass of perfluorobutyl iodide.

3. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mass ratio of perfluorobutyl iodide to sodium pyrosulfite in S1 is 0.8-1.2:

1.

4. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mass ratio of water to acetonitrile in the S1 is 1:2.8-3.

2.

5. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mass ratio of perfluorobutyl iodide to water in S1 is 1:2.8-3.

3.

6. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mixture in S1 is heated to 50-60° C. and then perfluorobutyl iodide is added to react to obtain a solid.

7. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mass percentage of the hydrochloric acid solution in S2 is 4-6%.

8. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The S2 is specifically as follows: dissolving the solid with hydrochloric acid solution, cooling the mixture to 10-15° C., and introducing chlorine gas to react until the reaction liquid turns black, thereby obtaining perfluorobutylsulfonyl fluoride.

9. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The mass ratio of perfluorobutanesulfonyl chloride, potassium fluoride and water in S3 is 1:3.5-4.5:

2.

10. The method for synthesizing perfluorobutylsulfonyl fluoride according to claim 1, characterized in that: The reaction condition of S3 is to carry out the reaction at 50-60°C.

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