Preparation method of 1,3-propane sultone

Abstract

The present invention provides a kind of preparation method of 1,3-propane sultone, comprising the following steps: using allyl acetate and sulfite as reaction raw materials, fully reacting under the action of initiator and solvent, generating 3-acetate propane sulfonate; then adding strong base to the obtained reaction solution, maintaining the solution pH at 12-14, carrying out hydrolysis reaction; then adding sulfuric acid solution to the obtained reaction solution, generating 3-hydroxypropane sulfonic acid after acidification, adding alcohol solvent after reduced pressure concentration, collecting purified 3-hydroxypropane sulfonic acid after fully reacting; purified 3-hydroxypropane sulfonic acid is subjected to reduced pressure distillation to obtain 1,3-propane sultone. By the above manner, the present invention can safely prepare high yield, high purity 1,3-propane sultone with low toxicity raw materials and mild reaction conditions simply and efficiently, greatly reducing raw materials and operating costs, and being easy to realize industrialization.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and in particular to a method for preparing 1,3-propane sultone. Background Art

[0002] 1, 3-Propane sultone is an organic compound, a colorless transparent crystal (below 31°C), which can be used as a surfactant, pharmaceutical intermediate, synthetic sulfonating agent and lithium battery electroplating additive, etc. Its structural formula is as follows:

[0003] .

[0004] With the development of 1,3-propane sultone applications in various fields, its market demand is also increasing. At present, the methods for synthesizing 1,3-propane sultone mainly include the following:

[0005] (1) Taking the synthesis scheme of KHARASCH, JOC, 2.175-192 (1938) as an example, this synthesis scheme uses allyl alcohol as a raw material and carries out sulfonation addition with sulfite to synthesize 3-hydroxypropane sulfonic acid, and then carries out intramolecular dehydration of 3-hydroxypropane sulfonic acid at high temperature to prepare 1, 3-propane sultone. Patents with publication numbers CN106146453A and CN108218828A are both process optimizations based on this. However, allyl alcohol is a flammable liquid, volatile and highly toxic, which increases the danger in the preparation process.

[0006] (2) Patent publication number CN104803967A provides a method for preparing 1,3-propane sultone. The patent uses allyl chloride as a raw material, and carries out substitution sulfonation with allyl chloride by sulfite, and then carries out anti-Markovnikov addition with sulfuric acid to generate an intermediate, which is then hydrolyzed under alkaline conditions, and then acidified to obtain 3-hydroxypropanesulfonic acid, and finally cyclized and dehydrated in the presence of an inert dehydrating agent to obtain 1,3-propane sultone. However, the raw material allyl chloride of this method is a flammable liquid, which is corrosive and toxic, and the preparation process is relatively dangerous.

[0007] (3) Patent publication number CN108164502A provides a method for preparing 1,3-propane sultone, which involves reacting 1,3-dichloropropane and sulfur dioxide in the presence of tetraethylammonium bromide and under constant current in acetonitrile to obtain 1,3-propane sultone, and finally oxidizing with an oxidant to generate 1,3-propane sultone. The raw materials 1,3-dichloropropane and sulfur dioxide in this method are highly toxic and corrosive, and the requirements for the reaction container during the reaction are relatively high.

[0008] In addition to the high toxicity of the raw materials, the reaction conditions of the above-mentioned methods for synthesizing 1,3-propane sultone are also relatively harsh, requiring high temperature, high pressure or electric current treatment, which is difficult to handle in production, is not conducive to industrialization, safe production and environmental protection, and the yield and purity of the obtained 1,3-propane sultone product still need to be improved.

[0009] In view of this, it is necessary to design an improved method for preparing 1,3-propane sultone to solve the above problems. Summary of the invention

[0010] In view of the above-mentioned defects of the prior art, the object of the present invention is to provide a method for preparing 1,3-propane sultone, which can simply, efficiently and safely prepare high-yield and high-purity 1,3-propane sultone with low-toxic raw materials and mild reaction conditions.

[0011] To achieve the above object, the present invention provides a method for preparing 1,3-propane sultone, comprising the following steps:

[0012] S1, using allyl acetate and sulfite as reaction raw materials, fully reacting under the action of an initiator and a solvent to generate 3-acetate propane sulfonate;

[0013] S2, adding a strong base to the reaction solution obtained in step S1 to maintain the pH of the solution at 12-14, and performing a hydrolysis reaction;

[0014] S3, adding sulfuric acid solution to the reaction solution obtained in step S2, generating 3-hydroxypropane sulfonic acid after acidification, adding an alcohol solvent after reduced pressure concentration, collecting purified 3-hydroxypropane sulfonic acid after sufficient reaction;

[0015] S4, distilling the purified 3-hydroxypropane sulfonic acid under reduced pressure to obtain 1,3-propane sultone.

[0016] As a further improvement of the present invention, in step S1, the reaction temperature is 20-50° C., and the reaction time is 3-8 h.

[0017] As a further improvement of the present invention, in step S1, the molar ratio of allyl acetate to sulfite is 1:1-2, the molar ratio of allyl acetate to initiator is 1:0.01-0.2, and the mass ratio of sulfite to solvent is 1:5-10.

[0018] As a further improvement of the present invention, in step S1, the sulfite includes one of sodium sulfite, ammonium sulfite, potassium sulfite, sodium bisulfite, ammonium bisulfite, and potassium bisulfite; the initiator is sodium thiosulfate or peroxide; and the solvent is deionized water.

[0019] As a further improvement of the present invention, in step S2, the temperature of the hydrolysis reaction is 20-50° C., and the reaction time is 3-6 hours.

[0020] As a further improvement of the present invention, in step S2, the strong base includes one of sodium hydroxide, lithium hydroxide, and calcium hydroxide, and the molar ratio of hydroxide to sulfite in the strong base is 1~1.1:1.

[0021] As a further improvement of the present invention, in step S3, the sulfuric acid solution is a sulfuric acid aqueous solution with a concentration of 10-50wt%; the molar ratio of sulfuric acid in the sulfuric acid solution to the strong base is 0.5-1:1.

[0022] As a further improvement of the present invention, in step S3, the temperature of the acidification treatment is 40-80° C., and the treatment time is 0.5-2 h.

[0023] As a further improvement of the present invention, in step S3, the alcohol solvent is one of ethanol, isopropanol, n-butanol and n-pentanol.

[0024] As a further improvement of the present invention, in step S4, the vacuum degree during the reduced pressure distillation process is 10-80 Pa, and the collection temperature of the distillate is 110-150°C.

[0025] The beneficial effects of the present invention are:

[0026] 1. The preparation method of 1,3-propane sultone provided by the present invention is to use low-toxic allyl acetate as the main reaction raw material, so that it reacts with sulfite under the action of an initiator to generate a free radical addition reaction to generate 3-acetyl propane sulfonate; after the reaction is completed, a strong base is added to hydrolyze the product after the addition, and then sulfuric acid is added to prepare 3-hydroxypropane sulfonic acid by the principle of strong acid to weak acid, and an alcohol solvent is used for extraction to remove salts and organic byproducts in 3-hydroxypropane sulfonic acid to obtain a high-purity intermediate product 3-hydroxypropane sulfonic acid; finally, the target product 1,3-propane sultone can be obtained by vacuum distillation. Compared with the prior art, the preparation method of 1,3-propane sultone provided by the present invention has the advantages of low raw material toxicity, safe reaction, simple process, etc., greatly reducing raw material and operating costs, and the molar yield can reach more than 95%, and the purity of the obtained 1,3-propane sultone can reach 99.9%, which has a high practical application value.

[0027] 2. The preparation method of 1,3-propane sultone provided by the present invention, by selecting allyl acetate as a reaction raw material, can not only improve the safety of the reaction based on its low toxicity, but also because allyl acetate itself has a certain solubility in water, the reaction process does not need to add a phase transfer catalyst, and the initiator can form a stable mixed solution with allyl acetate and water, and only one drop-addition high-level tank is needed in the actual production process, which effectively reduces the equipment investment. The present invention can reduce the temperature required for the synthesis reaction, shorten the reaction time, and improve the conversion rate of allyl acetate by further preferably sodium thiosulfate as an initiator; on this basis, after strong alkalization and sulfuric acid acidification, by further preferably n-pentanol as an alcohol solvent for extraction, the purity of 3-hydroxypropane sulfonic acid can be greatly improved, and the n-pentanol used can also be recovered by reduced pressure concentration; finally, by adopting molecular distillation technology, the preparation and separation of 1,3-propane sultone can be made economical and efficient, and the obtained product has a high yield and high purity, and is economical, environmentally friendly, and easy to realize industrialization. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below in conjunction with specific embodiments.

[0029] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0030] The present invention provides a method for preparing 1,3-propane sultone, comprising the following steps:

[0031] S1, using allyl acetate and sulfite as reaction raw materials, fully reacting under the action of an initiator and a solvent to generate 3-acetate propane sulfonate;

[0032] S2, adding a strong base to the reaction solution obtained in step S1 to maintain the pH of the solution at 12-14, and performing a hydrolysis reaction;

[0033] S3, adding sulfuric acid solution to the reaction solution obtained in step S2, generating 3-hydroxypropane sulfonic acid after acidification, adding an alcohol solvent after reduced pressure concentration, collecting purified 3-hydroxypropane sulfonic acid after sufficient reaction;

[0034] S4, distilling the purified 3-hydroxypropane sulfonic acid under reduced pressure to obtain 1,3-propane sultone.

[0035] In step S1, the order of adding the raw materials and the reaction conditions are preferably as follows: first, the sulfite and the solvent are mixed and stirred, and the temperature is maintained at 20-50° C., and then a mixed solution of allyl acetate and an initiator is added dropwise, and the reaction is carried out for 3-8 hours to react allyl acetate to generate 3-acetate propane sulfonate. Preferably, the molar ratio of allyl acetate to sulfite is 1: 1-2, the molar ratio of allyl acetate to initiator is 1: 0.01-0.2, and the mass ratio of sulfite to solvent is 1: 5-10.

[0036] The sulfite includes but is not limited to one of sodium sulfite, ammonium sulfite, potassium sulfite, sodium bisulfite, ammonium bisulfite, and potassium bisulfite; the solvent is preferably deionized water; the initiator is sodium thiosulfate or peroxide, and the peroxide includes but is not limited to hydrogen peroxide and tert-butyl hydroperoxide. The initiator is preferably sodium thiosulfate and hydrogen peroxide, more preferably sodium thiosulfate, which can not only reduce the temperature required for the synthesis reaction, shorten the reaction time, and increase the conversion rate of allyl acetate, but also the process of inducing free radicals is milder than that of hydrogen peroxide.

[0037] In step S2, the strong base includes one of sodium hydroxide, lithium hydroxide, and calcium hydroxide, preferably sodium hydroxide; the molar ratio of hydroxide to sulfite in the strong base is preferably 1-1.1:1; the temperature of the hydrolysis reaction is preferably 20-50°C, and the reaction time is preferably 3-6h.

[0038] In step S3, the sulfuric acid solution is preferably a sulfuric acid aqueous solution with a concentration of 10-50wt%; the molar ratio of sulfuric acid in the sulfuric acid solution to the strong base is preferably 0.5-1:1; the temperature of the acidification treatment is preferably 40-80°C, and the treatment time is preferably 0.5-2h.

[0039] In step S3, after adding an alcohol solvent and stirring, the solution is further allowed to stand at 0-10°C for 1-3 hours and then filtered to remove salt from the solution to purify the solution to obtain an alcohol solution of 3-hydroxypropane sulfonic acid. The alcohol solvent is one of ethanol, isopropanol, n-butanol, and n-pentanol, more preferably n-pentanol. When n-pentanol is used as the alcohol solvent, after obtaining the purified n-pentanol solution of 3-hydroxypropane sulfonic acid, water is preferably added for extraction, and the aqueous phase is taken to obtain a purified aqueous solution of 3-hydroxypropane sulfonic acid, which can greatly improve the purity of 3-hydroxypropane sulfonic acid.

[0040] In step S4, the vacuum degree during the reduced pressure distillation is preferably 10-80 Pa, and the collection temperature of the fraction is preferably 110-150° C., more preferably 130-140° C.

[0041] By the above method, the purity of the prepared 1, 3-propane sultone can reach 99.9%, and the molar yield can reach more than 95%. In addition, the overall preparation process has the advantages of low raw material toxicity, safe reaction, simple process, etc., which greatly reduces the raw material and operation costs, is easy to realize industrialization, and has high practical application value.

[0042] The preparation method of 1,3-propane sultone provided by the present invention is described in detail below with reference to specific embodiments.

[0043] Example 1

[0044] This embodiment provides a method for preparing 1,3-propane sultone, which specifically comprises the following steps:

[0045] S1. In a 3000 L three-necked flask equipped with a mechanical stirrer, a thermometer, and a dropping device, add 520 g (5 mol) of sodium bisulfite and 3000 g of deionized water and stir. After the solution is heated to 40°C, add 500 g (5 mol) of allyl acetate and 4.5 g (0.25 mol) of initiator hydrogen peroxide and stir for 4 hours. The allyl acetate content is less than 1% when sampled and measured. The reaction is completed to generate sodium 3-acetate propane sulfonate. The reaction equation is as follows:

[0046]

[0047] S2. Add 200 g (5 mol) of sodium hydroxide solid to the reaction solution obtained in step S1, maintain the pH of the solution at 14, and stir the reaction at 50° C. for 5 hours. The reaction equation is as follows:

[0048]

[0049] S3. After the reaction in step S2 is completed, 1250 mL (5 mol) of a 40 wt% sulfuric acid aqueous solution is slowly added dropwise to the reaction solution, and the reaction temperature is controlled to be maintained within the range of 40-60°C. After the addition of concentrated sulfuric acid is completed, the reaction is continued with stirring for 1 hour. The reaction equation is as follows:

[0050]

[0051] After the reaction is completed, the reaction solution is concentrated under reduced pressure and 1000 g of n-pentanol is added and stirred. After standing at 0-4°C for 2 hours, the solution is filtered to obtain a purified n-pentanol solution of 3-hydroxypropane sulfonic acid, and water is further added for extraction. The aqueous phase is taken to obtain a purified 3-hydroxypropane sulfonic acid aqueous solution.

[0052] S4. The 3-hydroxypropane sulfonic acid aqueous solution obtained in step S3 is placed under a vacuum condition of 60-70 Pa for vacuum distillation, and the fractions at 130-140° C. are collected to obtain 585 g of high-purity 1,3-propane sultone, with a measured purity of 99.9% and a calculated molar yield of 95.9%.

[0053] Example 2

[0054] This embodiment provides a method for preparing 1,3-propane sultone, which specifically comprises the following steps:

[0055] S1. In a 3000 L three-necked flask equipped with a mechanical stirrer, a thermometer and a dropping device, add 252 g (2 mol) of sodium sulfite and 2000 g of deionized water and stir. After the solution is heated to 40°C, add 200 g (2 mol) of allyl acetate and 15.8 g (0.1 mol) of sodium thiosulfate as an initiator and stir for 3 hours. The allyl acetate content is less than 1% when sampled and the reaction is completed to generate sodium 3-acetate propane sulfonate.

[0056] S2. Add 74 g (1 mol) of solid calcium hydroxide to the reaction solution obtained in step S1, maintain the pH of the solution at 14, and stir the reaction at 70° C. for 3 hours.

[0057] S3. After the reaction in step S2 is completed, 1000 mL (2 mol) of a 20 wt% aqueous sulfuric acid solution is slowly added dropwise to the reaction solution, and the reaction temperature is controlled to be maintained within the range of 40-60°C. After the addition of concentrated sulfuric acid is completed, the reaction is continued to be stirred for 1 hour. After the reaction is completed, the reaction solution is concentrated under reduced pressure and 500 g of n-pentanol is added and stirred and mixed. After standing at 0-4°C for 2 hours, the solution is filtered to obtain a purified n-pentanol solution of 3-hydroxypropane sulfonic acid, and water is further added for extraction, and the aqueous phase is taken to obtain a purified 3-hydroxypropane sulfonic acid aqueous solution.

[0058] S4. The 3-hydroxypropane sulfonic acid aqueous solution obtained in step S3 is placed under a vacuum condition of 60-70 Pa for vacuum distillation, and the fractions at 130-140° C. are collected to obtain 235 g of high-purity 1,3-propane sultone, the purity of which is measured to be 99.9%, and the molar yield is calculated to be 96.3%.

[0059] Example 3

[0060] This embodiment provides a method for preparing 1,3-propane sultone, which specifically comprises the following steps:

[0061] S1. In a 3000 L three-necked flask equipped with a mechanical stirrer, a thermometer and a dropping device, add 139 g (1.2 mol) of ammonium sulfite and 1000 g of deionized water and stir. After the solution is heated to 40°C, add 120 g (1.2 mol) of allyl acetate and 0.9 g (0.05 mol) of initiator hydrogen peroxide and stir for 3 hours. The allyl acetate content is less than 1% when sampled and the reaction is completed to generate 3-acetate propane ammonium sulfonate.

[0062] S2. Add 44.4 g (0.6 mol) of solid calcium hydroxide to the reaction solution obtained in step S1, maintain the pH of the solution at 14, and stir the reaction at 70° C. for 3 hours.

[0063] S3. After the reaction in step S2 is completed, 1200 mL (1.2 mol) of a 10 wt% aqueous sulfuric acid solution is slowly added dropwise to the reaction solution, and the reaction temperature is controlled to be maintained within the range of 40-60°C. After the concentrated sulfuric acid is added dropwise, the reaction is continued to stir for 1 hour. After the reaction is completed, the reaction solution is concentrated under reduced pressure and 200 g of n-pentanol is added and stirred and mixed. After standing at 0-4°C for 2 hours, the solution is filtered to obtain a purified n-pentanol solution of 3-hydroxypropane sulfonic acid, and water is further added for extraction, and the aqueous phase is taken to obtain a purified 3-hydroxypropane sulfonic acid aqueous solution.

[0064] S4. The 3-hydroxypropane sulfonic acid aqueous solution obtained in step S3 is placed under a vacuum condition of 60-70 Pa for vacuum distillation, and the fractions at 130-140° C. are collected to obtain a total of 142 g of high-purity 1,3-propane sultone, the purity of which is measured to be 99.9%, and the molar yield is calculated to be 96.9%.

[0065] Example 4

[0066] This embodiment provides a method for preparing 1,3-propane sultone. Compared with Example 2, the only difference is that the initiator is changed from 0.1 mol of sodium thiosulfate to 0.1 mol of tert-butyl hydroperoxide, and the reaction time in step S1 is extended to 8 h. The remaining steps and parameters are consistent with Example 2 and are not repeated here.

[0067] A total of 232 g of 1,3-propane sultone was prepared in this example, and its purity was measured to be about 98%, and the molar yield was calculated to be 93.1%. Compared with Example 2, it can be seen that when tert-butyl hydroperoxide is used as an initiator for this reaction, a longer reaction time is required, and the purity and molar yield of the reaction product are lower than those in Example 2.

[0068] Example 5

[0069] This embodiment provides a method for preparing 1,3-propane sultone. Compared with Example 3, the only difference is that 200 g of n-pentanol is replaced by 200 g of anhydrous ethanol. After obtaining the purified ethanol solution of 3-hydroxypropane sulfonic acid, water is not added for extraction, but the ethanol is removed by concentrating to dryness under reduced pressure. The remaining steps and parameters are the same as those in Example 3 and are not repeated here.

[0070] A total of 140 g of 1,3-propane sultone was prepared in this example, and its purity was measured to be about 98%, and the molar yield was calculated to be 93.7%. Compared with Example 3, it can be seen that when using alcohol solvents such as ethanol or methanol that are easily soluble in water, it is impossible to use extraction to separate the product, and most of the solvent can only be removed by vacuum distillation, and a small amount of solvent is likely to remain, resulting in reduced product purity and yield.

[0071] In summary, the present invention provides a method for preparing 1,3-propane sultone, comprising the following steps: using allyl acetate and sulfite as reaction raw materials, fully reacting under the action of an initiator and a solvent to generate 3-acetate propane sulfonate; then adding a strong base to the obtained reaction solution to maintain the pH of the solution at 12-14, and performing a hydrolysis reaction; then adding a sulfuric acid solution to the obtained reaction solution, generating 3-hydroxypropane sulfonic acid after acidification, adding an alcohol solvent after reduced pressure concentration, collecting purified 3-hydroxypropane sulfonic acid after sufficient reaction; performing reduced pressure distillation on the purified 3-hydroxypropane sulfonic acid to obtain 1,3-propane sultone. Through the above manner, the present invention can simply and efficiently prepare high-yield, high-purity 1,3-propane sultone with low toxicity raw materials and mild reaction conditions, greatly reducing raw material and operating costs, and easy to achieve industrialization.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing 1,3-propane sultone, characterized in that: The steps include: S1, using allyl acetate and sulfite or bisulfite as reaction raw materials, fully reacting under the action of an initiator and a solvent to generate 3-acetate propane sulfonate; S2, adding a strong base to the reaction solution obtained in step S1 to maintain the pH of the solution at 12-14, and performing a hydrolysis reaction; S3, adding sulfuric acid solution to the reaction solution obtained in step S2, generating 3-hydroxypropane sulfonic acid after acidification, adding an alcohol solvent after reduced pressure concentration, collecting purified 3-hydroxypropane sulfonic acid after sufficient reaction; S4, distilling the purified 3-hydroxypropane sulfonic acid under reduced pressure to obtain 1,3-propane sultone.

2. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S1, the reaction temperature is 20-50°C, and the reaction time is 3-8h.

3. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S1, the molar ratio of allyl acetate to sulfite or bisulfite is 1:1-2, the molar ratio of allyl acetate to initiator is 1:0.01-0.2, and the mass ratio of sulfite or bisulfite to solvent is 1:5-10.

4. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S1, the sulfite includes one of sodium sulfite, ammonium sulfite and potassium sulfite; the bisulfite includes one of sodium bisulfite, ammonium bisulfite and potassium bisulfite; the initiator is sodium thiosulfate or peroxide; and the solvent is deionized water.

5. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S2, the temperature of the hydrolysis reaction is 20-50°C, and the reaction time is 3-6 hours.

6. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S2, the strong base includes one of sodium hydroxide, lithium hydroxide, and calcium hydroxide, and the molar ratio of hydroxide to sulfite or bisulfite in the strong base is 1-1.1:

1.

7. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S3, the sulfuric acid solution is a sulfuric acid aqueous solution with a concentration of 10-50 wt %; the molar ratio of sulfuric acid to the strong base in the sulfuric acid solution is 0.5-1:

1.

8. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S3, the temperature of the acidification treatment is 40-80°C, and the treatment time is 0.5-2h.

9. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S3, the alcohol solvent is one of ethanol, isopropanol, n-butanol and n-pentanol.

10. The method for preparing 1,3-propane sultone according to claim 1, characterized in that: In step S4, the vacuum degree during the reduced pressure distillation process is 10-80 Pa, and the collection temperature of the distillate is 110-150°C.

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