Preparation method of 3-fluoro-1, 3-propane sultone

Abstract

The invention relates to a preparation method of 3-fluoro-1, 3-propane sultone, and belongs to the technical field of preparation of battery electrolyte additives, and the preparation method comprises the following steps: S1, dissolving a sulfonating reagent in water, adding an initiator and acrolein dimethyl acetal, heating to 40-100 DEG C, and reacting for 2-10 hours to generate an intermediate 3, 3-dimethoxy propyl sulfonic acid; s2, cooling, adjusting to acidity, spin-drying a water phase, extracting, carrying out suction filtration, and spin-drying a solvent to obtain 3-formyl propyl sulfonic acid; s3, the temperature is increased to 50 DEG C to 200 DEG C, and 3-hydroxy-1, 3-propane sultone is obtained through cyclization; and S4, carrying out a fluorination reaction on the 3-hydroxy-1, 3-propane sultone and a fluorination reagent, removing the solvent after the reaction is completed to obtain a crude product, and carrying out recrystallization purification to obtain the product 3-fluoro-1, 3-propane sultone. The preparation method disclosed by the invention is simple to operate, and the obtained 3-fluoro-1, 3-propane sultone is high in purity and high in yield.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation of battery electrolyte additives and relates to a method for preparing 3-fluoro-1,3-propane sultone. Background Art

[0002] 1,3-Propane sultone is a new functional fine chemical material. It reacts with a wide range of compounds under very mild conditions, accurately providing sulfonic acid groups, thereby imparting new properties (such as hydrophilicity and antistatic properties) to these compounds. It is an excellent general-purpose sulfonating agent and an important intermediate for the synthesis of electroplating additives. It is an important pharmaceutical intermediate and a key raw material for lithium battery production. It is also used in brighteners, dyes, diionic surfactants, and sulfonating agents. It can also be used in lithium secondary batteries to increase cycle life and enhance battery life.

[0003] 3-Fluoro-1,3-propane sultone is a modified product of 1,3-propane sultone. It can effectively reduce the low-temperature resistance of the negative electrode interface film and improve the low-temperature performance of the battery. Therefore, with the booming electric vehicle industry, 3-Fluoro-1,3-propane sultone has important applications and commercial prospects.

[0004] Currently known preparation methods of 3-fluoro-1,3-propane sultone all have common defects: many side reactions, complex post-processing, difficulty in purification, and low yield and product purity.

[0005] The synthesis process of the existing patent (CN118184624A) is to chlorinate 1,3-propane sultone in the presence of a catalyst to generate chlorinated products at the 2- and 3-positions, which are then separated by cooling and crystallization to obtain 3-chloro-1,3-propane sultone, which is then fluorinated to obtain 3-fluoro-1,3-propane sultone. The separation process is somewhat difficult. Summary of the Invention

[0006] The purpose of the present invention is to provide a process scheme which is simple to operate and can obtain a high-purity 3-chloro-1,3-propane sultone product.

[0007] The present invention adopts the following technical solutions to achieve its purpose:

[0008] The preparation method of 3-fluoro-1,3-propane sultone comprises the following steps:

[0009] S1. Dissolve the sulfonating reagent in water, add the initiator and acrolein dimethyl acetal, raise the temperature to 40-100 ° C and react for 2-10 hours to generate the intermediate 3,3-dimethoxypropyl sulfonic acid;

[0010] S2 cooled to 20 ° C, adjusted to acidic, the aqueous phase was dried, extracted, filtered, and the solvent was dried to obtain 3-aldehyde propyl sulfonic acid;

[0011] S3. Heating to 50-200°C, and obtaining 3-hydroxy-1,3-propane sultone by cyclization;

[0012] S4. 3-hydroxy-1,3-propane sultone is subjected to a fluorination reaction with a fluorination agent. After the reaction is completed, the solvent is removed to obtain a crude product, which is then purified by recrystallization to obtain the product 3-fluoro-1,3-propane sultone.

[0013] Furthermore, the sulfonation reagent includes but is not limited to one of sodium bisulfite, sodium metabisulfite, potassium bisulfite, and potassium metabisulfite.

[0014] Furthermore, the molar ratio of the sulfonating agent to acrolein dimethyl acetal is 1:1-5:1.

[0015] Furthermore, the initiator is selected from one or more of benzoyl peroxide, azobisisobutyronitrile, di-tert-butyl peroxide, and tert-butyl hydroperoxide.

[0016] Furthermore, in step S1, the reaction temperature is 60-100° C., and the reaction time is 3-6 h.

[0017] Furthermore, in step S2, acid is used to adjust the mixture to acidity, wherein the acid includes but is not limited to one of sulfuric acid, hydrochloric acid, phosphoric acid, and acetic acid.

[0018] Furthermore, in step S2, the solvent used for extraction includes but is not limited to one of methanol, ethanol, isopropanol, n-propanol, n-butanol, methyl tert-butyl ether, tetrahydrofuran, ethyl acetate, acetonitrile, and N,N-dimethylformamide.

[0019] Furthermore, in step S3, the temperature is raised to 50-200° C., and the cyclization reaction is carried out for 2-10 hours under vacuum conditions of -0.01 MPa-0.1 MPa, and then extracted, purified, and dried to obtain 3-hydroxy-1,3-propane sultone, wherein the extractant is one of dichloromethane, dichloroethane, ethyl acetate, and methyl tert-butyl ether.

[0020] Furthermore, in step S3, the temperature is raised to 140-160° C., and the cyclization reaction is carried out for 3-5 hours under a vacuum degree of -0.095 MPa-0.1 MPa, and then extracted, purified, and dried to obtain 3-hydroxy-1,3-propane sultone.

[0021] Furthermore, in step S4, the solvent for the fluorination reaction includes but is not limited to one of acetonitrile, tetrahydrofuran, dichloromethane, dichloroethane, and ethylene glycol dimethyl ether; the reaction temperature is -20 to 80°C; the fluorination reagent is one of diethylaminosulfur trifluoride and bis(2-methoxyethyl)aminosulfur trifluoride; the reaction time is 2 to 48 hours; the recrystallization solvent is one of acetonitrile, tetrahydrofuran, dichloromethane, dichloroethane, ethylene glycol dimethyl ether, and ethyl acetate; the molar ratio of 3-hydroxy-1,3-propane sultone to the fluorination reagent is 1:(1-3).

[0022] The beneficial effects of the present invention are:

[0023] The preparation method of the present invention is simple to operate, and the obtained 3-fluoro-1,3-propane sultone has high purity and high yield. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0025] The synthetic route of the present invention is as follows:

[0026]

[0027] Example 1

[0028] Add 500 ml of deionized water to a 1 L reaction flask, add 0.45 mol of sodium bisulfite, and stir to dissolve; add 0.3 mol of acrolein dimethyl acetal and 0.9 g of azobisisobutyronitrile, heat to 60 ° C and keep warm for 1 hour, then heat to 80 ° C and keep warm for 4 hours to stop the reaction.

[0029] The mixture was cooled to 20°C, adjusted to pH 1 with hydrochloric acid, and then heated to 60°C for 2 h. The aqueous phase was dried to obtain a solid, which was extracted with 2 × 300 ml of methanol. The undissolved solid was removed by filtration, and the methanol was removed in vacuo to obtain a viscous liquid (3-formylpropylsulfonic acid).

[0030] The resulting viscous liquid was stirred at 150°C under a vacuum of -0.1 MPa to remove the generated water. After 4 hours, the mixture was cooled to room temperature, and the vacuum was slowly released. 200 ml of deionized water and 500 ml of dichloromethane were added at -5 to 0°C, stirred for 10 minutes, and the liquids were separated. The solvent was removed from the organic phase to obtain a white solid. The solid was dried under vacuum at 40°C for 2 hours to obtain 35.52 g of 3-hydroxy-1,3-propane sultone. The yield was 85.71% and the purity was 98.72%.

[0031] The dried 3-hydroxy-1,3-propane sultone was placed in a 500ml reaction flask and dissolved in 500ml of dichloromethane. The temperature was then cooled to -5°C and maintained between -5 and 0°C. 49.74g of diethylaminosulfur trifluoride was slowly added dropwise. After the addition was complete, the reaction was allowed to react for 2h. The reaction solution was then slowly added dropwise to ice water to quench the reaction. After the addition was complete, the mixture was stirred for 10min, separated, and the organic phase was dried over molecular sieves. The dichloromethane was removed, and the resulting solid was dissolved in 500ml of dichloroethane at 60°C. The temperature was then lowered to 0°C to precipitate crystals, which were filtered and dried to yield 30.44g of 3-fluoro-1,3-propane sultone, with a yield of 84.48% and a purity of 99.26%.

[0032] Example 2

[0033] Add 400 ml of deionized water to a 1 L reaction flask, add 0.18 mol of sodium metabisulfite, stir to dissolve, add 0.24 mol of acrolein dimethyl acetal and 0.72 g of azobisisobutyronitrile, heat to 60 ° C and keep warm for 0.5 h, then heat to 80 ° C and keep warm for 3 h to stop the reaction.

[0034] Cool to 20°C, adjust the pH to 1 with sulfuric acid, and then heat to 70°C for 1 hour. Spin dry the aqueous phase to obtain a solid. Extract with 2 x 250 ml of methanol, remove the undissolved solid by filtration, and remove the methanol in vacuo to obtain a viscous liquid.

[0035] The resulting viscous liquid was stirred at 160°C under a vacuum of -0.1 MPa to remove the generated water. After 3 hours, the mixture was cooled to room temperature. The vacuum was slowly released, and 200 ml of deionized water and 500 ml of dichloromethane were added at -5-0°C. The mixture was stirred for 10 minutes, separated, and the solvent was removed from the organic phase to obtain a white solid. The solid was dried under vacuum at 40°C for 2 hours to obtain 27.83 g of 3-hydroxy-1,3-propane sultone. The yield was 83.94% and the purity was 98.38%.

[0036] The dried 3-hydroxy-1,3-propane sultone was placed in a 500ml reaction flask and dissolved in 400ml of dichloromethane. The temperature was then cooled to -5°C and maintained between -5 and 0°C. 38.97g of diethylaminosulfur trifluoride was slowly added dropwise. After the addition was complete, the reaction was allowed to react for 2h. The reaction solution was slowly added dropwise to ice water to quench the reaction. After the addition was complete, the mixture was stirred for 10min. The liquid phase was separated, and the organic phase was dried over molecular sieves to remove the dichloromethane. The resulting solid was dissolved in 400ml of dichloroethane at 60°C, then cooled to 0°C to precipitate crystals, filtered, and dried. 24.61g of 3-fluoro-1,3-propane sultone was obtained, with a yield of 87.18% and a purity of 99.31%.

[0037] Example 3

[0038] Add 400 ml of deionized water to a 1 L reaction flask, add 0.18 mol of potassium metabisulfite, stir to dissolve, add 0.24 mol of acrolein dimethyl acetal and 0.72 g of azobisisobutyronitrile, heat to 60 ° C and keep warm for 1 hour, then heat to 80 ° C and keep warm for 3 hours to stop the reaction.

[0039] The mixture was cooled to 20°C, adjusted to pH 1 with hydrochloric acid, and then heated to 60°C for 2 h. The aqueous phase was dried to obtain a solid. The mixture was extracted with 3 × 250 ml of ethanol, and the undissolved solid was removed by filtration. The methanol was then removed in vacuo to obtain a viscous liquid.

[0040] The resulting viscous liquid was stirred at 150°C under a vacuum of -0.1 MPa to remove the generated water. After 4 hours, the mixture was cooled to room temperature, the vacuum was slowly released, and 200 ml of deionized water and 500 ml of dichloromethane were added at -5 to 0°C. The mixture was stirred for 10 minutes, separated, and the solvent was removed from the organic phase to obtain a white solid. The solid was dried under vacuum at 40°C for 2 hours to obtain 28.61 g of 3-hydroxy-1,3-propane sultone, with a yield of 86.30% and a purity of 98.86%.

[0041] The dried 3-hydroxy-1,3-propane sultone was placed in a 500ml reaction flask and dissolved in 400ml of dichloromethane. The temperature was lowered to -5°C and maintained between -5 and 0°C. 39.81g of diethylaminosulfur trifluoride was slowly added dropwise. After the addition was complete, the reaction was incubated for 2h. The reaction solution was slowly added dropwise to ice water to quench the solution. After the addition was complete, the mixture was stirred for 10min, separated, and the organic phase was dried over molecular sieves to remove the dichloromethane. The resulting solid was dissolved in 250ml of ethyl acetate at 60°C, then cooled to 0°C to precipitate crystals, filtered, and dried to obtain 25.32g of 3-fluoro-1,3-propane sultone, with a yield of 87.24% and a purity of 99.22%.

[0042] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-mentioned embodiments, ordinary technicians in this field should understand that any technician familiar with this technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed by the present invention, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered by the protection scope of the present invention.

Claims

1. A method for preparing 3-fluoro-1,3-propane sultone, characterized in that: The following steps are involved: S1. Dissolve the sulfonating reagent in water, add the initiator and acrolein dimethyl acetal, raise the temperature to 40-100 ° C and react for 2-10 hours to generate the intermediate 3,3-dimethoxypropyl sulfonic acid; S2 cooled to 20 ° C, adjusted to acidic, the aqueous phase was dried, extracted, filtered, and the solvent was dried to obtain 3-aldehyde propyl sulfonic acid; S3. Heating to 50-200°C, and obtaining 3-hydroxy-1,3-propane sultone by cyclization; S4. 3-hydroxy-1,3-propane sultone is subjected to a fluorination reaction with a fluorination agent. After the reaction is completed, the solvent is removed to obtain a crude product, which is then purified by recrystallization to obtain the product 3-fluoro-1,3-propane sultone.

2. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, wherein The sulfonation reagent includes but is not limited to one of sodium bisulfite, sodium metabisulfite, potassium bisulfite, and potassium metabisulfite.

3. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, wherein The molar ratio of the sulfonating reagent to the acrolein dimethyl acetal is 1:1-5:

1.

4. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, wherein The initiator is selected from one or more of benzoyl peroxide, azobisisobutyronitrile, di-tert-butyl peroxide, and tert-butyl hydroperoxide.

5. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: In step S1, the reaction temperature is 60-100° C., and the reaction time is 3-6 h.

6. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: In step S2, acid is used to adjust the mixture to acidity, wherein the acid includes but is not limited to one of sulfuric acid, hydrochloric acid, phosphoric acid, and acetic acid.

7. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: In step S2, the solvent used for extraction includes but is not limited to one of methanol, ethanol, isopropanol, n-propanol, n-butanol, methyl tert-butyl ether, tetrahydrofuran, ethyl acetate, acetonitrile, and N,N-dimethylformamide.

8. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: In step S3, the temperature is raised to 50-200° C., and a cyclization reaction is carried out for 2-10 hours under a vacuum degree of -0.01 MPa-0.1 MPa, followed by extraction, purification, and drying to obtain 3-hydroxy-1,3-propane sultone, wherein the extractant is one of dichloromethane, dichloroethane, ethyl acetate, and methyl tert-butyl ether.

9. The method for preparing 3-fluoro-1,3-propane sultone according to claim 8, characterized in that: In step S3, the temperature is raised to 140-160° C., and a cyclization reaction is carried out for 3-5 hours under a vacuum degree of -0.095 MPa-0.1 MPa, followed by extraction, purification, and drying to obtain 3-hydroxy-1,3-propane sultone.

10. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: In step S4, the solvent for the fluorination reaction includes but is not limited to one of acetonitrile, tetrahydrofuran, dichloromethane, dichloroethane, and ethylene glycol dimethyl ether; the reaction temperature is -20 to 80° C.; the fluorination reagent is one of diethylaminosulfur trifluoride and bis(2-methoxyethyl)aminosulfur trifluoride; the reaction time is 2 to 48 hours; the recrystallization solvent is one of acetonitrile, tetrahydrofuran, dichloromethane, dichloroethane, ethylene glycol dimethyl ether, and ethyl acetate; and the molar ratio of 3-hydroxy-1,3-propane sultone to the fluorination reagent is 1:(1-3).

Images