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

Abstract

The invention provides a preparation method of 3-fluoro-1, 3-propane sultone, which comprises the following steps: (1) carrying out sulfonation reaction on a reactant (II) and sulfite in a solvent to obtain an intermediate compound (III); and (2) reacting the intermediate compound (III) prepared in the step (1) with a solvent and a fluorinating agent to prepare a compound (I), namely 3-fluoro-1, 3-propane sultone. The preparation method has the characteristics of convenient and easily available raw materials, short route, high total yield and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of synthesis of electrolyte additives for new energy batteries. Specifically, the present application relates to a method for preparing 3-fluoro-1,3-propane sultone, which can be used as a non-aqueous electrolyte additive in lithium-ion secondary batteries. Background Art

[0002] 3-Fluoro-1,3-propane sultone (3-FPS) is a derivative of 1,3-propane sultone. In addition to being used as a pharmaceutical intermediate, brightener, diionic surfactant and sulfonating agent, it can also be used as an additive for lithium-ion secondary battery electrolytes to improve battery cycle life and enhance battery safety.

[0003] The structure of the 3-fluoro-1,3-propane sultone is as follows:

[0004]

[0005] Regarding the synthesis and preparation methods of 3-fluoro-1,3-propane sultone, the existing reports mainly include the following: ① KR20070022968A and CN103044384A use 1,3-propane sultone to undergo chlorination reaction in the presence of a chlorinating agent and an initiator, and then exchange halogen with a fluorinating agent in the presence of a phase transfer catalyst to prepare 3-fluoro-1,3-propane sultone; ② JP5313579A uses 1,3 -Propane sultone and potassium fluoride and hydrofluoric acid are subjected to electrolytic fluorination reaction in a constant temperature bath at -40 to 0°C, and finally 3-fluoro-1,3-propane sultone is obtained through post-treatment; ③ Patents CN113549047A and CN105037320A disclose that 1,3-propane sultone is used as a raw material, and a fluorinating agent such as SO2F2 or Deoxo-Fluro is used to directly undergo a carbon-hydrogen bond direct fluorination reaction to obtain 3-fluoro-1,3-propane sultone.

[0006] In the previously disclosed methods for preparing 3-fluoro-1,3-propane sultone, the free radical chlorination using 1,3-propane sultone as the starting material exhibits poor selectivity. This results in the formation of 2-chloro-1,3-propane sultone and ring-opening byproducts during the preparation of the 3-chloro-1,3-propane sultone intermediate. Furthermore, due to the poor stability of the chlorosultone intermediate, the fluorination reaction typically requires relatively high temperatures and alkaline conditions, resulting in low final product yields and a high number of byproducts. This makes the purification of 3-fluoro-1,3-propane sultone challenging. Electrolytic fluorination using 1,3-propane sultone as the starting material suffers from poor selectivity and low yields. Direct fluorination using fluorinating agents such as sulfuryl fluoride is prone to the formation of various fluorinated sultone byproducts, making product separation and purification difficult and resulting in low yields. Therefore, developing synthetic routes with improved overall yields, environmental friendliness, and ease of production remains of great value. Summary of the Invention

[0007] The present invention addresses many problems existing in existing synthesis technologies and provides a new method for preparing 3-fluoro-1,3-propane sultone. The preparation method provided by the present invention has the advantages of low raw material cost, simple reaction route, safe operation process, easy product purification, and high yield.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] The present invention provides a method for preparing 3-fluoro-1,3-propane sultone, which comprises the following steps:

[0010] Step (1): sulfonating the reactant (II) with sulfite in a solvent to obtain an intermediate compound (III);

[0011] Step (2): reacting the intermediate compound (III) prepared in step (1) with a solvent and a fluorinating agent to prepare compound (I), i.e., 3-fluoro-1,3-propane sultone;

[0012] The chemical reaction formula is as follows:

[0013]

[0014] Among them, R 1 、R 2 Independently selected from C1-C5 linear, branched or cyclic alkyl groups, or C1-C5 linear or branched alkyl groups containing fluorine atoms, chlorine atoms or ether bonds;

[0015] X is a halogen atom or other leaving group;

[0016] M is selected from metal ions.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention provides a method for preparing 3-fluoro-1,3-propane sultone. This process features highly active raw materials, simple reaction conditions, easy product purification, minimal environmental pollution, and suitability for industrial production. The method utilizes reactant (II) and sulfite to prepare intermediate compound (III), resulting in a mild reaction and high yield. The preparation of compound (I) (3-fluoro-1,3-propane sultone) from reactant (III) is simple and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is shown that the 3-fluoro-1,3-propane sultone (3-FPS) of the present invention 1 H-NMR spectrum.

[0020] Figure 2 It is shown that the 3-fluoro-1,3-propane sultone (3-FPS) of the present invention 13 C-NMR spectrum.

[0021] Figure 3 It is shown that the 3-fluoro-1,3-propane sultone (3-FPS) of the present invention 19 F-NMR spectrum. DETAILED DESCRIPTION

[0022] The following describes in detail an embodiment of a method for preparing 3-fluoro-1,3-propane sultone of the present application.

[0023] Definition of terms

[0024] Unless otherwise specified, the following words, phrases and symbols used in this specification generally have the meanings described below.

[0025] In general, the nomenclature used herein (e.g., IUPAC nomenclature) and the laboratory procedures described below (including for cell culture, organic chemistry, analytical chemistry, and pharmacology, etc.) are those well known and commonly used in the art. Unless otherwise defined, all scientific and technical terms used herein in conjunction with the present disclosure described herein have the same meaning as commonly understood by those skilled in the art. Additionally, in the claims and / or the specification, when the term "one" or "an" is used in conjunction with the term "comprising" or a noun, its meaning may be "one", but is also consistent with the meaning of "one or more", "at least one", and "one or more than one". Similarly, the term "another" or "other" may mean at least a second or more.

[0026] It should be understood that whenever various aspects are described herein using the terms "including" or "comprising," other similar aspects described by "consisting of" and / or "consisting essentially of" are also provided.

[0027] As used herein, the term "alkyl" used alone or in combination may be linear, branched or cyclic, and may have, for example, C1-C5, C1-C4, C1-C3, C1-C2, etc. For example, alkyl includes, but is not limited to, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopropyl, cyclobutyl, cyclopentyl, etc.

[0028] As used herein, the term "halogen," alone or in combination, refers to fluorine, chlorine, bromine or iodine.

[0029] Herein, the leaving group may be, for example, -OMs or -OTs.

[0030] Preparation method of 3-fluoro-1,3-propane sultone

[0031] The present invention provides a method for preparing 3-fluoro-1,3-propane sultone, wherein the structure of the 3-fluoro-1,3-propane sultone (3-FPS) is shown in formula (I):

[0032]

[0033] In the present invention, 3-fluoro-1,3-propane sultone is prepared from reactant (II) as a starting material, first undergoes a sulfonation reaction to generate an intermediate compound (III), and then undergoes acidolysis, cyclization, and fluorination reactions to obtain compound (I).

[0034] The synthetic route is as follows:

[0035]

[0036] Among them, R 1 、R 2 Independently selected from C1-C5 linear, branched or cyclic alkyl groups, or C1-C5 linear or branched alkyl groups containing fluorine atoms, chlorine atoms or ether bonds.

[0037] Optionally, R 1 、R 2 is independently selected from (C1-C4 or C1-C3) linear, branched or cyclic alkyl. 1 、R 2 For example, they can be independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl, cyclopropyl, cyclobutyl, cyclopentyl and the like.

[0038] Optionally, R 1 、R 2 are independently selected from (C1-C4 or C1-C3) straight or branched chain alkyl groups containing fluorine atoms, chlorine atoms or ether bonds. 1 、R 2 Independently selected from -CF3, -CHF2, -CH2F, -CH2-CF3, -CH2-CHF2, -CH2-CH2F, -CH2CF2CF2H, -CH(CF3)2, -CCl3, -CHCl2, -CH2Cl, -CH2-CCl3, -CH2-CHCl2, -CH2-CH2Cl, etc.

[0039] Optionally, R 1 、R 2 independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl, cyclopropyl, cyclobutyl, cyclopentyl, -CF3, -CHF2, -CH2F, -CH2-CF3, -CH2-CHF2, -CH2-CH2F, -CH2CF2CF2H, -CH(CF3) 2、 -CCl3, -CHCl2, -CH2Cl, -CH2-CCl3, -CH2-CHCl2, -CH2-CH2Cl.

[0040] X is a halogen atom or other leaving groups, wherein the halogen atom can be selected from, for example, Cl, Br, and I, and the other leaving groups can be selected from, for example, -OMs or -OTs.

[0041] M is a metal ion. For example, M can be Na + , K + or Li + .

[0042] Specifically, the above route includes the following steps:

[0043] Step (1): sulfonating the reactant (II) with sulfite in a solvent to obtain an intermediate compound (III);

[0044] Step (2): The intermediate (III) prepared in step (1) is subjected to cyclization and fluorination reaction with a solvent and a fluorinating agent to obtain compound (I), namely 3-fluoro-1,3-propane sultone.

[0045] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, the sulfite in step (1) is selected from one or more of lithium sulfite, sodium sulfite, and potassium sulfite.

[0046] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, the molar ratio of the reactant (II) to the sulfite in step (1) is 1:1 to 1:3. Alternatively, the molar ratio of the reactant (II) to the sulfite can be, for example, 1:1 to 1:2, 1:1 to 1:1.25, 1:1 to 1:1.3, 1:1.25 to 1:3, 1:1.25 to 1:1.3, or 1:2 to 1:3.

[0047] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, the solvent described in step (1) is a mixture of a short-chain alcohol and water. The short-chain alcohol is selected from at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, and tert-butanol. The mass (w / w) ratio of the short-chain alcohol to water is 1:(0.1-10). Alternatively, the mass (w / w) ratio of the short-chain alcohol to water can be, for example, 1:(0.1-2), 1:(2-10), 1:(2-5), 1:(5-10), 1:(0.1-1), 1:(1-10), 1:(1-5), 1:(5-10), 1:(1-3), 1:(3-5), 1:(5-8), 1:(8-10), etc.

[0048] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, step (1) is carried out under heating reflux conditions, and the reaction temperature is 60 to 120° C. Alternatively, the reaction temperature can be, for example, 60 to 85° C., 85 to 120° C., 60 to 80° C., 80 to 100° C., or 100 to 120° C.

[0049] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, the reactant (II) can be, for example, 3-halopropionaldehyde dialkyl acetal. Furthermore, the reactant (II) is selected from one or more of 3-bromopropionaldehyde dimethyl acetal, bromopropionaldehyde diethyl acetal, 2-(2-bromoethyl)-1,3-dioxane, 2-(2-bromoethyl)-1,3-dioxane, 3-bromo-1,1-diethoxypropane, and the like.

[0050] In the preparation method of 3-fluoro-1,3-propane sultone provided by the present invention, the intermediate compound (III) can be, for example, 3,3-dimethoxypropane-1-sulfonate. Further, 3,3-dimethoxypropane-1-sulfonate is selected from 3,3-dimethoxypropane-1-sulfonate lithium, 3,3-dimethoxypropane-1-sulfonate sodium, 3,3-dimethoxypropane-1-sulfonate potassium, 3,3-diethoxy-1-propanesulfonate lithium, 3,3-diethoxy-1-propanesulfonate sodium, 3,3-diethoxy-1-propanesulfonate potassium, 2-(1,3-dioxolane-2- One or more of 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate, and 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate.

[0051] In the preparation method of 3-fluoro-1,3-propane sultone provided by the present invention, the crude product of step (1) is concentrated, filtered, and dried to obtain an intermediate compound (III). Specifically, as a more preferred technical solution, after the crude product is concentrated, an organic solvent is added for pulping, the slurry is filtered to obtain a filter cake, and the filter cake is dried to obtain an intermediate compound (III), for example, the intermediate compound (III) is an intermediate containing 3,3-dimethoxypropane-1-sulfonate, which can be directly used in the next step. As a more preferred technical solution, the above-mentioned organic solvent is one or more of ethyl acetate, isopropyl acetate, methyl tert-butyl ether, methylcyclohexane, and toluene.

[0052] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, in step (2), the solvent is selected from HF, and the molar ratio of the intermediate compound (III) to the solvent is 1:(4-50). Alternatively, the molar ratio of the intermediate compound (III) to the solvent can be, for example, 1:(4-10), 1:(10-20), 1:(20-30), 1:(30-40), or 1:(40-50).

[0053] In the preparation method of 3-fluoro-1,3-propane sultone provided by the present invention, the fluorinating agent in step (2) can specifically be HF, F2, SO2F2, diethylamino sulfur trifluoride, bis(2-methoxyethyl)amine sulfur trifluoride, 2-pyridinesulfonyl fluoride, N-fluoro-N'-(chloromethyl)triethylenediamine bis(tetrafluoroborate), perfluorobutylsulfonyl fluoride, One or more of fluorine reagent, 4-chloro-N-[(4-methylphenyl)sulfonyl]benzenesulfonyl fluoride.

[0054] As a preferred technical solution, the fluorinating agent used in step (2) is selected from one or more of HF (hydrofluoric acid), F2, SO2F2, diethylaminosulfur trifluoride, bis(2-methoxyethyl)aminesulfur trifluoride, 2-pyridinesulfonyl fluoride, perfluorobutylsulfonyl fluoride, and 4-chloro-N-[(4-methylphenyl)sulfonyl]benzenesulfonamide fluoride. Alternatively, the fluorinating agent is HF (hydrofluoric acid), SO2F2, or diethylaminosulfur trifluoride.

[0055] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, the amount of the fluorinating agent used in step (2) is based on 1.0 molar equivalent of the intermediate compound (III), and the molar ratio of the intermediate compound (III) to the fluorinating agent in step (2) is 1.0:(1.0-5.0). Alternatively, the molar ratio of the intermediate compound (III) to the fluorinating agent in step (2) can be, for example, 1.0:(1.0-3.0), 1.0:(3.0-5.0), 1.0:(1.0-2.0), 1.0:(2.0-3.0), 1.0:(3.0-4.0), 1.0:(4.0-5.0), etc.

[0056] In the method for preparing 3-fluoro-1,3-propane sultone provided by the present invention, the reaction temperature in step (2) is -60 to 20° C. Alternatively, the reaction temperature in step (2) can be, for example, -60 to -40° C., -40 to -20° C., -20 to 0° C., 0 to 10° C., 0 to 20° C., etc.

[0057] In the preparation method of 3-fluoro-1,3-propane sultone provided by the present invention, after obtaining compound (I) in step (2), a post-treatment step is further included. As a preferred technical solution, the post-treatment in step (2) includes operations such as filtration, desolventization, and recrystallization. After the reaction is completed, the reaction solution is subjected to post-treatment operations such as filtration, desolventization, and recrystallization to obtain 3-fluoro-1,3-propane sultone.

[0058] 3-Fluoro-1,3-propane sultone

[0059] Another aspect of the present invention provides 3-fluoro-1,3-propane sultone, which is prepared by the method of the first aspect of the present invention.

[0060] application

[0061] Another aspect of the present invention provides the use of 3-fluoro-1,3-propane sultone in a lithium ion battery electrolyte additive.

[0062] The technical solution of the present application is described clearly and completely below in conjunction with the embodiments of the present invention. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by professionals in this field based on the above-mentioned contents of the present invention still fall within the scope of protection of the present invention.

[0063] In the following examples, all reagents, materials and instruments used are commercially available unless otherwise specified.

[0064] The present invention has no special limitation on the sources of the common reaction reagents. In the embodiment of the present invention, the fluorinating agents used are hydrofluoric acid, SO2F2, diethylaminosulfur trifluoride, N,N'-difluoro-2,2'-bipyridyl bis tetrafluoroborate, XeF2, BAST, Fluorine reagents, 1-fluoropyridine trifluoromethanesulfonate, etc. were purchased from Shanghai Titan Technology Co., Ltd.

[0065] The analytical methods used in the following examples are as follows:

[0066] (1) NMR spectra were obtained on a BRUKER 400. Unless otherwise stated, the solvents CDCl3, D2O, CD3OD and DMSO-d 6 All were purchased from Shanghai Titan Technology Co., Ltd.

[0067] (2) GC data were obtained on an Agilent 8860 gas chromatograph using an HP-530m*0.32mm*0.25um column.

[0068] Example 1

[0069] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0070] (1) Synthesis of sodium 3,3-dimethoxypropane-1-sulfonate

[0071] To a 500 mL three-necked flask, 50 g of 3-bromopropanal dimethyl acetal (273.2 mmol, 1.0 equiv), 43.0 g of sodium sulfite (341.5 mmol, 1.25 equiv), 150 g of methanol, and 300 g of water were added sequentially. The reaction mixture was heated to 85°C and refluxed for approximately 15 h. After cooling, the reaction solution was concentrated to obtain a wet product. 200 g of ethyl acetate was added to the mixture, and the mixture was slurried and filtered. The filter cake was dried to yield sodium 3,3-dimethoxypropane-1-sulfonate (57.6 g) as a white solid, which was used directly in the next step.

[0072] Spectral characterization of sodium 3,3-dimethoxypropane-1-sulfonate:

[0073] 1 H NMR (400MHz, D2O) δ4.59 (t, J = 4.0Hz, 1H), 3.34 (s, 6H), 2.88 (m, 2H), 1.99 (m, 2H).

[0074] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0075] To the 57.6 g white solid obtained in step 1) was added 250 g of hydrofluoric acid (used as both a solvent and a fluorinating agent), and the reaction was allowed to proceed at 0-10°C for 2 h. HF was removed by desolventizing and recovery, and 200 g of dichloromethane and 100 g of water were added. The layers were separated, and the organic phase was washed once with 100 g of water, dried over anhydrous sodium sulfate, filtered, and desolventized to precipitate a solid. 50 g of isopropyl acetate was added, stirred at 40°C, and dissolved. The mixture was cooled to -10°C to precipitate 33.3 g of a white solid, with a two-step yield of 87% and a purity of 99.0%.

[0076] Spectral characterization of 3-fluoro-1,3-propane sultone:

[0077] 1 H NMR (400MHz, CDCl3) δ6.27 (dd, J1=59.2Hz, J2=3.6Hz, 1H), 3.44-3.40 (m, 2H), 2.98-2.74 (m, 2H).

[0078] 13 C NMR (101MHz, CDCl3) δ 107.3 (d, J = 240.4, 1C), 41.9 (s, 1C), 30.9 (d, J = 24.7, 1C).

[0079] 19 F NMR (376MHz, CDCl3) δ-118.3 (s, 1F).

[0080] Example 2

[0081] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0082] (1) Synthesis of sodium 3,3-diethoxypropane-1-sulfonate

[0083] To a 1L three-necked flask, 100g of bromopropionaldehyde diethyl acetal (474mmol, 1.0equiv), 77.6g of sodium sulfite (616mmol, 1.3equiv), 250g of ethanol, and 250g of water were added in sequence. The reaction mixture was heated to 80°C for approximately 20 hours, monitored by gas chromatography, until the conversion of the bromopropionaldehyde diethyl acetal was complete. The reaction solution was concentrated under reduced pressure until no significant solvent was evaporated. 300g of isopropyl acetate was added to slurry the mixture, and the solid was filtered and dried under vacuum to obtain crude sodium 3,3-diethoxypropane-1-sulfonate (162g), which was used directly in the next reaction.

[0084] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0085] To the crude sodium 3,3-diethoxypropane-1-sulfonate (162 g) obtained in step (1) above, 500 g of hydrofluoric acid was added, and the mixture was reacted at 0-10°C for 3 h. HF was recovered by desolventizing. 300 g of dichloromethane and 200 g of water were added, and the mixture was allowed to stand for separation. The organic phase was separated and washed once with 200 g of water, dried over anhydrous sodium sulfate, filtered, and desolventized to precipitate a solid. 100 g of isopropyl acetate was added, stirred at 40°C, and dissolved. The mixture was cooled to -10°C to precipitate 54.4 g of a white solid, with a two-step yield of 82% and a purity of 99.2%.

[0086] Example 3

[0087] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0088] (1) Synthesis of sodium 2-(1,3-dioxolane-2-yl)ethane-1-sulfonate

[0089] To a 500 mL three-necked flask, 50 g of 2-(2-bromoethyl)-1,3-dioxane (276.2 mmol, 1.0 equiv), 43.5 g of sodium sulfite (345.2 mmol, 1.25 equiv), 150 g of methanol, and 300 g of water were added sequentially. The reaction mixture was heated to 85°C and refluxed for 15 h. After cooling, the reaction solution was concentrated to obtain a wet product. 200 g of ethyl acetate was added to the slurry, and the mixture was filtered. The filter cake was dried to obtain sodium 2-(1,3-dioxolan-2-yl)ethane-1-sulfonate (97.2 g) as a white solid, which was used directly in the next reaction.

[0090] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0091] This example provides a method for preparing 3-fluoro-1,3-propane sultone. Other conditions are the same as those in Example 1, and 29.8 g of a white solid is obtained with a two-step yield of 77% and a purity of 99.0%.

[0092] Example 4

[0093] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0094] (1) Synthesis of sodium 2-(1,3-dioxan-2-yl)ethane-1-sulfonate

[0095] To a 500 mL three-necked flask, 50 g of 2-(2-bromoethyl)-1,3-dioxane (256.3 mmol, 1.0 equiv), 40.4 g of sodium sulfite (320.4 mmol, 1.25 equiv), 150 g of methanol, and 300 g of water were added sequentially. The reaction mixture was heated to 85°C and refluxed for approximately 15 h. After cooling, the reaction solution was concentrated to obtain a wet product. 200 g of ethyl acetate was added to the slurry, followed by filtration. The filter cake was dried to yield sodium 2-(1,3-dioxan-2-yl)ethane-1-sulfonate (90.4 g) as a white solid, which was used directly in the next reaction.

[0096] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0097] This example provides a method for preparing 3-fluoro-1,3-propane sultone. Other conditions are the same as those in Example 1, and 30.2 g of a white solid is obtained with a two-step yield of 84% and a purity of 99.0%.

[0098] Example 5

[0099] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0100] (1) Synthesis of sodium 3,3-diethoxypropane-1-sulfonate

[0101] To a 500 mL three-necked flask, 50 g of 3-bromo-1,1-diethoxypropane (236.8 mmol, 1.0 equiv), 37.3 g of sodium sulfite (296.1 mmol, 1.25 equiv), 150 g of methanol, and 300 g of water were added sequentially. The reaction mixture was heated to 85°C and refluxed for approximately 15 h. After cooling, the reaction solution was concentrated to obtain a wet product. 200 g of ethyl acetate was added to the slurry, followed by filtration. The filter cake was dried to yield sodium 3,3-diethoxypropane-1-sulfonate (87.4 g) as a white solid, which was used directly in the next reaction.

[0102] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0103] This example provides a method for preparing 3-fluoro-1,3-propane sultone, wherein the fluorinating agent is 48.4 g (473.6 mmol, 2.0 equiv) SO2F2 and 200 g HF (solvent). Other conditions are the same as those in Example 1. 28.5 g of a white solid is obtained with a two-step yield of 86% and a purity of 99.1%.

[0104] Example 6

[0105] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0106] (1) Synthesis of sodium 3,3-diethoxypropane-1-sulfonate

[0107] To a 500 mL three-necked flask, 50 g of 3-bromo-1,1-diethoxypropane (236.8 mmol, 1.0 equiv), 37.3 g of sodium sulfite (296.1 mmol, 1.25 equiv), 150 g of methanol, and 300 g of water were added sequentially. The reaction mixture was heated to 85°C and refluxed for approximately 15 h. After cooling, the reaction solution was concentrated to obtain a wet product. 200 g of ethyl acetate was added to the slurry, followed by filtration. The filter cake was dried to yield sodium 3,3-diethoxypropane-1-sulfonate (87.4 g) as a white solid, which was used directly in the next reaction.

[0108] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0109] This example provides a method for preparing 3-fluoro-1,3-propane sultone, wherein the fluorinating agent is 38.2 g (236.8 mmol, 1.0 equiv) of diethylaminosulfur trifluoride and 200 g of HF (solvent). Other conditions are the same as those in Example 1. 29.5 g of a white solid is obtained with a two-step yield of 89% and a purity of 99.3%.

[0110] Comparative Example 1

[0111] A method for preparing 3-fluoro-1,3-propane sultone comprises the following reaction steps:

[0112] (1) Synthesis of sodium 3,3-diethoxypropane-1-sulfonate

[0113] The operation and dosage are the same as in Example 6.

[0114] (2) Synthesis of 3-fluoro-1,3-propane sultone

[0115] This comparative example provides a method for preparing 3-fluoro-1,3-propane sultone, wherein the fluorinating agent is 37.9 g (1894.4 mmol, 8.0 equiv) of HF and 200 g of dichloromethane (solvent), and other conditions are the same as those in Example 1. 2.5 g of a white solid is obtained with a two-step yield of 7.5% and a purity of 99.0%.

[0116] The applicant declares that while the present invention uses the above-mentioned examples to illustrate the method for preparing 3-fluoro-1,3-propane sultone, the present invention is not limited to the above-mentioned examples, and does not necessarily rely on the above-mentioned examples for implementation. Those skilled in the art should understand that any improvements to the present invention, equivalent replacements for the raw materials of the product of the present invention, addition of auxiliary ingredients, and selection of specific methods, etc., fall within the scope of protection and disclosure of the present invention.

[0117] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0118] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A method for preparing 3-fluoro-1,3-propane sultone, characterized in that: The preparation method comprises the following steps: Step (1): reacting reactant (II) with sulfite in a solvent to obtain an intermediate compound (III); Step (2): reacting the intermediate compound (III) prepared in step (1) with a solvent and a fluorinating agent to prepare compound (I), i.e., 3-fluoro-1,3-propane sultone; The chemical reaction formula is as follows: Among them, R 1 、R 2 Independently selected from C1-C5 linear, branched or cyclic alkyl groups, or C1-C5 linear or branched alkyl groups containing fluorine atoms, chlorine atoms or ether bonds; X is a halogen atom or other leaving group; M is selected from metal ions.

2. The preparation method of 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: Also includes any one or more of the following features: A1) the sulfite in step (1) is selected from one or more of lithium sulfite, sodium sulfite, and potassium sulfite; A2) in step (1), the molar ratio of the reactant (II) to the sulfite is 1:1 to 1:3; A3) the solvent in step (1) is a mixture of a short-chain alcohol and water; A4) the reaction temperature in step (1) is 60 to 120°C; A5) The crude product from step (1) is concentrated, filtered, and dried to obtain the intermediate compound (III).

3. The method for preparing 3-fluoro-1,3-propane sultone according to claim 2, wherein Also includes any one or more of the following features: A31) In feature A3), the short-chain alcohol is selected from at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, and tert-butanol; A32) In feature A3), the mass (w / w) ratio of the short-chain alcohol to water is 1:(0.1-10); A51) In feature A5), the crude product is concentrated and then slurried with an organic solvent. The slurry is filtered to obtain a filter cake, which is then dried to obtain the intermediate compound (III).

4. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, wherein Also includes any one or more of the following features: B1) the halogen atom is selected from Cl, Br or I; B2) The other leaving group can be selected from -OMs or -OTs; B3) M is selected from Na + , K + or Li + ; B4)R 1 、R 2 Independently selected from methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl, cyclopropyl, cyclobutyl, cyclopentyl, -CF3, -CHF2, -CH2F, -CH2-CF3, -CH2-CHF2, -CH2-CH2F, -CH2CF2CF2H, -CH(CF3)2, -CCl3, -CHCl2, -CH2Cl, -CH2-CCl3, -CH2-CHCl2, -CH2-CH2Cl.

5. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: The intermediate compound (III) is 3,3-dimethoxypropane-1-sulfonate, and the 3,3-dimethoxypropane-1-sulfonate is selected from one or more of 3,3-dimethoxypropane-1-sulfonate lithium, 3,3-dimethoxypropane-1-sulfonate sodium, and 3,3-dimethoxypropane-1-sulfonate potassium.

6. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: The solvent is selected from HF, and the molar ratio of the intermediate compound (III) to the solvent is 1:(4-50).

7. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: The fluorinating agent in step (2) is selected from HF, F2, SO2F2, diethylaminosulfur trifluoride, bis(2-methoxyethyl)aminesulfur trifluoride, 2-pyridinesulfonyl fluoride, N-fluoro-N'-(chloromethyl)triethylenediaminebis(tetrafluoroborate), perfluorobutylsulfonyl fluoride, One or more of fluorine reagent, 4-chloro-N-[(4-methylphenyl)sulfonyl]benzenesulfonyl fluoride.

8. The method for preparing 3-fluoro-1,3-propane sultone according to claim 7, characterized in that: The fluorinating agent in step (2) is selected from one or more of HF, F2, SO2F2, diethylaminosulfur trifluoride, bis(2-methoxyethyl)aminesulfur trifluoride, 2-pyridinesulfonyl fluoride, perfluorobutylsulfonyl fluoride, and 4-chloro-N-[(4-methylphenyl)sulfonyl]benzenesulfonamide fluoride.

9. The method for preparing 3-fluoro-1,3-propane sultone according to claim 1, characterized in that: Also includes any one or more of the following features: C1) the amount of the fluorinating agent used in step (2), based on 1.0 molar equivalent of the intermediate compound (III), the molar ratio of the intermediate compound (III) to the fluorinating agent in step (2) is 1.0:(1.0-5.0); C2) the reaction temperature in step (2) is -60 to 20°C; C3) After obtaining compound (I) in step (2), the process further includes a post-treatment step.

10. The method for preparing 3-fluoro-1,3-propane sultone according to claim 9, characterized in that: In feature C3), the post-treatment includes filtration, desolventization, and recrystallization purification.

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