JP2016145147A - Manufacturing method of fluorosulfonylimide compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a fluorosulfonylimide compound safely, continuously and efficiently by preventing increase of manufacturing cost and outflow of corrosive materials out of a reaction system.SOLUTION: There is provided a method for providing a fluorosulfonylimide compound represented by the formula (1) by reacting a compound represented by the formula (2) and a compound represented by the composition formula (3) of 1 to 3 equivalence by stoichiometric amount based on 1 mol of the compound in a presence of a solvent of 0 to 4 mass times of the compound. (NHF(HF)(3), where Ris a C1 to 6 fluoroalkyl group, Ris halogen or a C1 to 6 fluoroalkyl group, Cat1and Cat2are monovalent groups and p is an integer of 0 to 10.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a fluorosulfonylimide compound.

Fluorosulfonylimide compounds such as bis (fluorosulfonyl) imide compounds and N- (fluorosulfonyl) -N- (fluoroalkylsulfonyl) imide compounds are useful as intermediates for compounds having an N (SO ₂ F) group, and It is a useful compound in various applications such as electrolytes, additives to fuel cell electrolytes, selective electrophilic fluorinating agents, photoacid generators, thermal acid generators, near-infrared absorbing dyes, etc. is there.

  Since the fluorosulfonyl imido onium salt which uses onium as a cation has excellent properties as an ionic liquid, various studies have been made focusing on the use of an electrolytic solution of an electrochemical device. Conventionally, as a method for producing a fluorosulfonylimide onium salt, a metal salt of fluorosulfonylimide obtained by reacting chlorosulfonylimide with an alkali metal fluoride or the like is subjected to cation exchange to synthesize a desired fluorosulfonylimide onium salt. Techniques have been adopted. However, since such a method once passes through a metal salt of fluorosulfonylimide, there is a problem that the product fluorosulfonylimide onium salt contains a metal salt as an impurity.

As a technique for suppressing the mixing of metal impurities into the product, Patent Documents 1 and 2 include 1 to 20 mol of hydrogen fluoride (HF) or ammonium fluoride (NH ₄ F) with respect to 1 mol of chlorosulfonylimide compound. A method of using and fluorinating a chlorosulfonylimide compound is disclosed.

International Publication No. 2012/108284 International Publication No. 2012/117916

  Thus, if hydrogen fluoride or ammonium fluoride is used as the fluorinating agent, mixing of metal impurities can be suppressed. However, in this case, the amount of the fluorinating agent tends to be very large, and there is a disadvantage that the cost increases as a result even if the raw material itself is inexpensive. Moreover, it is necessary to employ a relatively high reaction temperature in order to sufficiently advance the reaction, and HF having high corrosiveness is easily generated from unreacted raw materials. Further, this HF flows out of the reaction system of the fluorination reaction together with HCl produced as a by-product. Therefore, when industrially performing fluorination reactions, an increase in the amount of fluorinating agent combined with a high reaction temperature increases the discharge of corrosive substances, worsens the surrounding environment, There was a problem of deteriorating.

  The present invention has been made paying attention to the circumstances as described above, and its purpose is to suppress an increase in manufacturing cost, and to prevent the corrosive substance from flowing out of the reaction system, and to continue safely and continuously. It is an object to provide an efficient and efficient method for producing a fluorosulfonylimide compound.

  The production method of the present invention capable of achieving the above object is a production method of a fluorosulfonylimide compound represented by the following general formula (1),

(In the general formula (1), R ¹ is F, or represents a fluoroalkyl group having 1 to 6 carbon atoms, Cat1 ⁺ represents a monovalent cation represented by ^{R 2 R 3 R 4 R 5} N +, R ^{2 to} R ⁵ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms)
A compound represented by the general formula (2);

In (formula (2), R ⁶ is halogen, or represents a fluoroalkyl group having 1 to 6 carbon atoms, Cat2 ⁺ is hydrogen ion, or ^{R 2 R 3 R 4 R 5} N + represented monovalent be Represents a cation, and R ^{2 to} R ⁵ are the same as those in formula (1))

1 mol or more and 3 equivalents or less of a stoichiometric amount with respect to 1 mol of the compound represented by the general formula (2): General formula (3): NH ₄ F (HF) _p (in the general formula (3), p Represents an integer of 0 to 10), and includes a step of reacting a compound represented by the general formula (2) in the presence of 0 to 4 times by mass of a solvent.

  The above reaction is preferably carried out at 20 ° C. or higher and 75 ° C. or lower, and it is desirable to use at least one selected from the group consisting of nitriles and carboxylic acid esters as the solvent.

  The present invention also includes a method for producing a fluorosulfonylimide compound represented by the following general formula (5) by a reaction between the compound represented by the general formula (1) obtained by the above production method and an alkali metal compound. .

(In the general formula (5), R ¹ represents F or a fluoroalkyl group having 1 to 6 carbon atoms, and M represents an alkali metal)

  According to the present invention, since the amount of the fluorinating agent can be reduced, a fluorosulfonylimide compound can be efficiently produced at a high conversion rate while suppressing an increase in production cost. Also, by reducing the amount of fluorinating agent used, the amount of highly corrosive HF produced from the fluorinating agent can be reduced, so the amount of HF flowing out of the reaction system can also be reduced, preventing deterioration of the reaction equipment. The fluorosulfonylimide compound can be produced safely and continuously.

The production method of the present invention is a production method of a fluorosulfonylimide compound represented by the general formula (1), which is a compound represented by the general formula (2) and a compound represented by the general formula (2). 1 mol or more and 1 equivalent or less of the general formula (3): NH ₄ F (HF) _p (wherein p represents an integer of 0 to 10 in the general formula (3)) with respect to 1 mol. The compound represented by the present invention is characterized in that it is reacted in the presence of 0 to 4 mass times the solvent of the compound represented by the general formula (2).

(In the general formula (1), R ¹ is F, or represents a fluoroalkyl group having 1 to 6 carbon atoms, Cat1 ⁺ represents a monovalent cation represented by ^{R 2 R 3 R 4 R 5} N +, in the general formula (2), Cat2 ⁺ represents a monovalent cation represented by ⁺ hydrogen ions or ^{R 2 R 3 R 4 R 5} N, R 2 ~R 5 are the same or different and each represents a hydrogen atom or a carbon atoms It represents 1-6 alkyl group, R ⁶ represents halogen, or a fluoroalkyl group having 1 to 6 carbon atoms, p is an integer of 0.)

  The inventors of the present invention have been studying to provide a cheaper and more efficient method for producing a fluorosulfonylimide compound. As a result, the concentration of the chlorosulfonylimide compound (the compound represented by the general formula (2)) is increased. The present invention was completed by finding that a fluorosulfonylimide compound can be obtained at a high conversion rate even if the amount of the fluorinating agent is reacted in a high state even with a smaller amount of the fluorinating agent.

Although the detailed reason for obtaining a fluorosulfonylimide compound at a high conversion rate by the method of the present invention is not clear, the present inventors consider as follows. First, by reducing the amount of solvent used and increasing the solute concentration in the reaction solution, a chlorosulfonylimide compound (compound represented by the general formula (2)) and a fluorinating agent (general formula (3) are used. It is conceivable that the contact frequency with HF generated from the compound is increased, and as a result, the conversion rate from the chlorosulfonylimide compound to the fluorosulfonylimide compound is improved.
Secondly, by reducing the amount of solvent used, it is considered that the effect of eliminating HCl by-produced by the reaction out of the system (outside the reaction solution) is enhanced. That is, when HCl having a higher acidity than HF is excessively present in the reaction system, a salt is formed between the fluorinating agent (NH ₄ F (HF) _p ) used as a starting material and by-produced HCl. An exchange reaction (NH ₄ F (HF) _p + HCl → NH ₄ Cl + (p + 1) HF) occurs, and the possibility that HF flows out of the system before participating in the reaction increases. However, HCl having a very low boiling point (boiling point: −85 ° C.) cannot stay in the reaction system unless a medium such as a solvent is present, and immediately flows out of the reaction system. Therefore, the HCl concentration in the reaction system is low and the salt exchange reaction is difficult to occur under solvent-free conditions or under concentrated solution conditions where the solute concentration of the reaction solution is increased. It is considered that a fluorosulfonylimide compound can be obtained at a conversion rate.

  In the present invention, the term “fluorosulfonylimide” includes bis (fluorosulfonyl) imide having two fluorosulfonyl groups, N- (fluorosulfonyl) -N- (fluoroalkyl having a fluorosulfonyl group and a fluoroalkylsulfonyl group. (Sulfonyl) imide. Similarly, the term “chlorosulfonylimide” includes bis (chlorosulfonyl) imide and N- (chlorosulfonyl) -N- (fluoroalkylsulfonyl) imide. Hereinafter, the production method of the present invention will be described.

  In the present invention, a compound represented by the general formula (2) (hereinafter may be referred to as a compound (2) or a chlorosulfonylimide compound (2)) is used as a starting material.

In general formula (2), R ⁶ represents a halogen or a fluoroalkyl group having 1 to 6 carbon atoms. Examples of the halogen include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Preferably they are a fluorine atom or a chlorine atom.

Preferably carbon number of a fluoroalkyl group is 1-4, More preferably, it is 1-2. Specific examples of the fluoroalkyl group include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a fluoroethyl group, a difluoroethyl group, a 2,2,2-trifluoroethyl group, a pentafluoroethyl group, 3, 3, 3-trifluoropropyl group, perfluoro-n-propyl group, fluoropropyl group, perfluoroisopropyl group, fluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, perfluoro-n-butyl group, perfluoroisobutyl Group, perfluoro-t-butyl group, perfluoro-sec-butyl group, fluoropentyl group, perfluoro-n-pentyl group, perfluorohexyl group, perfluoro-n-hexyl group, pentafluoroisohexyl group and the like.
R ⁶ is preferably a fluorine atom, a chlorine atom, a trifluoromethyl group or a pentafluoroethyl group, more preferably a chlorine atom or a trifluoromethyl group.

Cation constituting the compound (2): Cat2 ⁺ is hydrogen ion (H ^+), or R ² R ³ R ⁴ R ⁵ is N ^+. Here, R ^{2 to} R ⁵ constituting the cation R ² R ³ R ⁴ R ⁵ N ⁺ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. It is preferable that carbon number of an alkyl group is 1-4, More preferably, it is 1-2. The alkyl group may be linear, branched, cyclic, or one having two or more structures. A linear or branched alkyl group is preferable, and a linear alkyl group is more preferable. Examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, s-butyl group, t-butyl group, pentyl group, hexyl group, and cyclohexyl group. .

General formula: Examples of the cation Cat2 ⁺ represented by ^{R 2 R 3 R 4 R 5} N + is tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, tetraheptylammonium ammonium, tetrahexyl ammonium, triethyl Quaternary ammoniums such as methylammonium; Tertiary ammoniums such as trimethylammonium, triethylammonium, tributylammonium, diethylmethylammonium, dimethylethylammonium, dibutylmethylammonium; Seconds such as dimethylammonium, diethylammonium, dibutylammonium Primary ammoniums; primary ammoniums such as methylammonium, ethylammonium, butylammonium, hexylammonium; and And ammonium represented by NH ₄ ⁺ .

When the cation Cat2 ⁺ of the compound (2) is R ² R ³ R ⁴ R ⁵ N ⁺ , no free proton is generated from the compound (2) during the fluorination reaction described later. The formation of HF due to the reaction between the compound and the compound (3) can be eliminated.

The compound (2) may contain one kind of cation Cat2 ^{+, or} may contain two or more kinds of cation Cat2 ⁺ . The cation Cat2 ⁺ is preferably a hydrogen ion, a quaternary ammonium, a tertiary ammonium, or an ammonium, more preferably a hydrogen ion, tetraethylammonium, triethylmethylammonium, trimethylammonium, triethylammonium, tributylammonium, and ammonium. More preferred are hydrogen ion, trimethylammonium, triethylammonium, tributylammonium, and ammonium. Particularly, when the cation Cat2 ⁺ is a hydrogen ion, triethylammonium, or ammonium, the reaction can proceed at a higher conversion rate, which is preferable. Moreover, when the cation Cat2 ⁺ is a hydrogen ion, the reaction of the cation exchange reaction of the compound (2) and the fluorination reaction of the compound (2) can be performed simultaneously, which is preferable because of high efficiency.

The compound (2) in which the cation Cat2 ⁺ is R ² R ³ R ⁴ R ⁵ N ⁺ is a chlorosulfonylimide compound represented by the following general formula (4) (hereinafter sometimes referred to as a chlorosulfonylimide compound (4)). A) and an ammonium compound (cation exchange reaction 1).

(In the general formula (4), R ⁶ represents a halogen or a fluoroalkyl group having 1 to 6 carbon atoms as in the general formula (2)).

  As the chlorosulfonylimide compound (4), a commercially available product may be used, or one synthesized by a conventionally known method may be used. The chlorosulfonylimide compound (4) is, for example, a reaction of chlorosulfonyl isocyanate obtained by the reaction of cyanogen chloride and sulfuric anhydride with chlorosulfonic acid (production method of bis (chlorosulfonyl) imide); chlorosulfonyl isocyanate And fluorinated alkylsulfonic acid, and fluorinated alkylsulfonyl isocyanate and chlorosulfonic acid (N- (chlorosulfonyl) -N- (fluoroalkylsulfonyl) imide)).

The ammonium compound, the cation constituting compounds described above and (2): a structure represented by ^{Cat2 + (R 2 R 3 R} 4 R 5 N +, R 2 ~R 5 are the same or different, An amine compound corresponding to a hydrogen atom or an alkyl group having 1 to 6 carbon atoms or a halide thereof, for example, ammonia (NH ₃ ); an alkyl group having 1 to 6 carbon atoms such as ethylamine or butylamine; Secondary amine having a C1-C6 alkyl group such as primary amine, diethylamine, diisopropylamine, etc., tertiary having a C1-C6 alkyl group such as triethylamine, tributylamine, ethyldiisopropylamine Amines such as amines; ammonium halides such as ammonium fluoride, ammonium chloride and ammonium bromide, trie Tertiary ammonium compounds such as tillammonium chloride and tributylammonium chloride; ammonium salts such as quaternary ammonium compounds such as tetraethylammonium chloride, tetrabutylammonium chloride and triethylmethylammonium chloride; and the like. Preferably, ammonia, quaternary amine, ammonium halide, tertiary ammonium compound, quaternary ammonium compound, more preferably ammonia, tertiary amine, ammonium halide, tertiary ammonium compound, More preferred are ammonia, triethylamine, ammonium chloride, and triethylammonium chloride.

  It is preferable that the usage-amount of an ammonium compound shall be 1 mol-5 mol with respect to 1 mol chlorosulfonyl imide compound (4). More preferably, it is 1 mol-2.5 mol.

  The reaction between the chlorosulfonylimide compound (4) and the ammonium compound may be carried out in the absence of a solvent, or may be carried out in the solvent used for the reaction between the chlorosulfonylimide compound (2) and the compound (3) described later. Good. When using a solvent for the reaction between the chlorosulfonylimide compound (4) and the ammonium compound, a chain nitrile solvent such as valeronitrile, isobutyronitrile, acetonitrile or the like, an ester such as ethyl acetate, propyl acetate, isopropyl acetate or butyl acetate Solvents and aromatic hydrocarbon solvents such as benzene, toluene and xylene are preferred, and toluene, acetonitrile, isobutyronitrile and valeronitrile are more preferred.

  The reaction conditions for the chlorosulfonylimide compound (4) and the ammonium compound are not particularly limited, and may be appropriately adjusted according to the amounts of the chlorosulfonylimide compound (4) and ammonium compound used as raw materials and the progress of the reaction. For example, the reaction temperature is preferably −10 ° C. to 100 ° C., more preferably 0 to 90 ° C., and further preferably 10 ° C. to 80 ° C. The reaction time is preferably 10 minutes to 1 hour, for example.

In the present invention, the stoichiometric amount of 1 equivalent or more and 3 equivalents or less of the compound represented by the above general formula (2) and 1 mol of the compound (2): NH ₄ F ( HF) A compound represented by _p (hereinafter sometimes referred to as compound (3)) is reacted in the presence of 0 to 4 times by mass solvent of compound (2) (fluorination reaction). In general formula (3), p represents an integer of 0 to 10. NH ₄ F (p = 0) or NH ₄ FHF (p = 1) is particularly preferable.

  The compound (3) is used in a stoichiometric amount of 1 to 3 equivalents with respect to 1 mol of the chlorosulfonylimide compound (2). Preferably it is 1 equivalent-2.5 equivalent, More preferably, it is 1 equivalent-1.5 equivalent. If the amount of the compound (3) used is too large, the production cost increases, and further, the compound (3) may be decomposed to generate a large amount of HF. On the other hand, if the amount used is too small, the fluorination reaction proceeds smoothly. There is a risk that the reaction stops. According to the present invention, since it is not necessary to use excessively the compound (3) which is a fluorinating agent, it is possible to suppress an increase in production cost and to reduce the amount of corrosive substances derived from the fluorinating agent Can do.

The chlorosulfonylimide compound (2) has 1 to 2 groups capable of reacting with the compound (3). Therefore, when using a compound in which p is 0 in the general formula (3) as the fluorinating agent (that is, NH ₄ F), “the amount of the compound (3) used is 1 mol of the chlorosulfonylimide compound (2), The stoichiometric amount of 1 equivalent or more and 3 equivalents or less "means that when R ⁶ is a fluorine atom or a fluoroalkyl group, for example, there is one functional group that can react with the compound (3). (2) It means that the compound (3) is used within a range of 1 mol to 3 mol with respect to 1 mol. In this case, the amount of the compound (3) used is preferably 1 mol to 2.5 mol, more preferably 1 mol to 1.5 mol. On the other hand, when R ⁶ is a halogen atom other than a fluorine atom, there are two functional groups that can react with the compound (3), so that “the amount of the compound (3) used is 1 mol of the chlorosulfonylimide compound (2)”. In contrast, the stoichiometric amount of 1 equivalent or more and 3 equivalents or less ”means that the compound (3) is used in the range of 2 mol to 6 mol with respect to 1 mol of the chlorosulfonylimide compound (2). The amount of compound (3) to be used is preferably 2 mol to 5 mol, more preferably 2 mol to 3 mol. In addition, when p is 1 in the general formula (3) (that is, NH ₄ F · HF), the fluorine atom contained in the compound (3) is doubled compared to when p = 0. The amount of the compound (3) used as the agent may be half of the above range. If the amount of the compound (3) used is too large, the production cost increases, and further, the compound (3) may be decomposed to generate a large amount of HF. On the other hand, if the amount used is too small, the fluorination reaction proceeds smoothly. There is a risk that the reaction stops. In the case where p is 2 or more in general formula (3), the amount of compound (3) used may be adjusted in the same manner.

  In the present invention, the chlorosulfonylimide compound (2) is reacted with the compound (3) in the presence of 0 mass times (that is, no solvent) to 4 mass times the solvent of the chlorosulfonylimide compound (2). By making the amount of the solvent used within the above range, the contact frequency between the chlorosulfonylimide compound (2) and HF generated from the compound (3) is increased, and HCl by-produced by the reaction is excluded from the reaction system. Since it becomes easy, even if it does not use compound (3) (fluorinating agent) excessively, a fluorination reaction can be advanced with high conversion.

  Examples of the solvent that can be used in the present invention include nitriles such as acetonitrile, isobutyronitrile, valeronitrile, and benzonitrile; chain carbonates such as dimethyl carbonate, ethylmethyl carbonate, and diethyl carbonate; ethylene carbonate, butylene carbonate , Cyclic carbonates such as propylene carbonate; cyclic esters such as γ-butyrolactone and γ-valerolactone; carboxylic acid esters such as methyl formate, methyl acetate, ethyl acetate, isopropylpyrate, butyl acetate, and methyl propionate; Chain or cyclic ethers such as methane, 1,2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, 4-methyl-1,3-dioxolane, cyclopentylmethyl ether Ters; linear or cyclic sulfones such as dimethyl sulfoxide, sulfolane and 3-methylsulfolane; nitro compounds such as nitromethane and nitrobenzene; nitrogen-containing compounds such as N, N-dimethylformamide and N-methyloxazolidinone; And aromatic hydrocarbon compounds such as toluene and xylene. From the viewpoint of allowing the reaction to proceed smoothly, the reaction is preferably carried out in the presence of at least one solvent selected from the group consisting of nitriles and carboxylic acid esters, or in the absence of a solvent. When the reaction is carried out in the presence of a solvent, at least one solvent selected from the group consisting of acetonitrile, isobutyronitrile, valeronitrile, ethyl acetate, isopropyl acetate, and butyl acetate is preferable. Acetonitrile, isobutyronitrile More preferred is at least one solvent selected from the group consisting of valeronitrile.

  The amount of the solvent is preferably 2 mass times or less, more preferably 1 mass times or less, and further preferably 0.5 mass times or less with respect to the chlorosulfonylimide compound (2). If the amount of the solvent used is too large, the production cost increases, which is not preferable. From the standpoint of reaction yield and conversion, the smaller the amount of solvent used, the better. On the other hand, it is also preferable to use a solvent from the viewpoint of production, and this is preferable because the stirring efficiency and heat transfer efficiency can be increased, and as a result, the reaction efficiency can be improved. When the starting material or product is a solid, the use of a solvent can suppress solid precipitation during the reaction, and can also be expected to suppress the deterioration of the reaction vessel. From this point, the amount of the solvent used is preferably 0.05 mass times or more, more preferably 0.1 mass times or more.

The reaction between the chlorosulfonylimide compound (2) and the compound (3) may be performed in the presence of ammonia or a primary to tertiary alkylamine having a linear alkyl group. When ammonia or the like is present in the reaction system, HF produced as a by-product from the compound (3) can be regenerated as a raw material (fluorinating agent). As a result, the outflow of corrosive HF to the outside of the reaction system is suppressed, and at the same time, the decrease in the concentration of the fluorinating agent in the reaction solution is also suppressed, so that the yield of the product fluorosulfonylimide can be improved. it can. In particular, when the cation Cat2 ⁺ of the compound (2) is a hydrogen ion, even if a cation exchange reaction occurs during the fluorination reaction, free protons generated from the compound (2) and Cl generated by the fluorination reaction are ammonia or the like. And the salt is formed, it is possible to prevent HF and HCl from being generated and flowing out of the reaction system. It is preferable that it is 1-4 as carbon number of the alkyl group which the said alkylamine has, More preferably, it is 1-2. Examples of primary to tertiary alkylamines having a linear alkyl group (hereinafter sometimes simply referred to as “alkylamines”) include alkyl groups having 1 to 4 carbon atoms such as methylamine, ethylamine, propylamine, and butylamine. Having primary alkylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, etc., secondary alkylamine having a C1-4 alkyl group, trimethylamine, triethylamine, tripropylamine, tributylamine, 1 to C1 And alkylamines such as tertiary alkylamines having 4 alkyl groups. Among these, from the viewpoint of versatility and handleability, tertiary alkylamines such as ammonia and triethylamine, and secondary alkylamines such as diethylamine are preferable, ammonia and triethylamine are more preferable, and ammonia is further preferable.

  The method for supplying ammonia or alkylamine (hereinafter sometimes referred to as “ammonia etc.”) into the reaction system is not particularly limited. For example, when ammonia or the like is a gas, a method of circulating the gas in the reaction vessel and dissolving it in the reaction solution, a method of circulating the gas through the reaction solution and supplying it into the reaction system by bubbling, gaseous ammonia or the like A method in which the total amount is dissolved in a solvent in advance as a solution (liquid) in the reaction system all at once or continuously, or the whole amount is divided into several times and added intermittently; ammonia or alkylamine is a liquid (solution of ammonia or the like) First) a method in which the whole amount of ammonia or the like is mixed with other raw materials, a method in which a part of the solution such as ammonia is first mixed with the other raw materials, and the rest is continuously fed, or intermittently. For example, a pulse addition method or a combination thereof. In addition, if ammonia or alkylamine is excessively present in the reaction system, the target product may be decomposed. Therefore, ammonia or alkylamine may be continuously or intermittently divided into several times in the reaction system. It is preferable to add. Specifically, a method of circulating gaseous ammonia or the like in the reaction vessel, a method of bubbling gaseous ammonia or the like into the reaction solution, a method of dissolving ammonia or the like in a solvent and dropping it into the reaction solution, a liquid alkylamine It is preferable to employ any one of the methods of dropping into the reaction solution. The supply of ammonia or the like is preferably started after mixing the chlorosulfonylimide compound (2) and the compound (3), and more preferably started before the temperature of the reaction solution is raised.

  Ammonia or alkylamine is preferably used in the range of 1 mol to 40 mol with respect to 1 mol of chlorosulfonylimide compound (2). More preferably, it is 1 mol-25 mol, More preferably, it is 5 mol-20 mol. The supply amount of ammonia or alkylamine per unit time into the reaction system is a stoichiometric amount with respect to the total amount of the chlorosulfonylimide compound (2) used as a raw material, and is 0.3 equivalent / hour to 10 equivalent / It is preferable to be within the time range. More preferably, it is 0.3 equivalent / hour to 7 equivalent / hour, and further preferably 1 equivalent / hour to 6 equivalent / hour.

  The reaction conditions are not particularly limited, and may be appropriately adjusted according to the amounts of the starting materials (2) and (3) used and the progress of the reaction. According to the present invention in which the chlorosulfonylimide compound (2) and the compound (3) are reacted in the presence of a specific amount of solvent, the fluorosulfonylimide compound can be obtained in a high yield even at a lower reaction temperature. The reaction temperature is, for example, preferably 20 ° C. or higher, more preferably 25 ° C. or higher, further preferably 40 ° C. or higher, preferably 100 ° C. or lower, more preferably 90 ° C. or lower, still more preferably 75 ° C. Or less, more preferably 60 ° C. or less. According to the present invention, since the reaction can proceed even at a relatively low temperature, it is possible to suppress HF as a by-product from flowing out of the reaction system as a gas. Moreover, since HF remaining in the reaction system is involved in the reaction as a fluorinating agent, the conversion rate to fluorosulfonylimide can be improved.

The reaction time can be confirmed by, for example, ¹⁹ F-NMR. That is, a peak appears in the chemical shift derived from fluorine as the reaction proceeds, and the relative intensity (integrated value) of the peak increases. Therefore, the completion of the fluorination reaction may be confirmed while tracking the progress of the reaction by ¹⁹ F-NMR. In addition, when reaction time is too long, since the production | generation of a by-product becomes remarkable, at the time (for example, about 0.5 to 24 hours from the start of reaction) when the relative intensity of the peak of a target object becomes the maximum. The fluorination reaction is preferably terminated. The reaction time is more preferably 1 hour or more, more preferably 10 hours or less, and even more preferably 6 hours or less.

  After completion of the reaction, the product may be isolated and purified, or the reaction solution may be used as it is as a starting material for other reactions. The purification method is not particularly limited, and conventionally known purification methods such as a reprecipitation method, a liquid separation extraction method, a recrystallization method, a crystallization method, and a purification method by chromatography can be employed. These purification methods may be implemented individually by 1 type, and may be implemented in combination of 2 or more type.

The fluorosulfonylimide compound (onium salt) represented by the general formula (1) is obtained by the production method of the present invention. In the general formula (1), R ¹ is F, or represents a fluoroalkyl group having 1 to 6 carbon atoms, Cat1 ⁺ represents a monovalent cation represented by ^{R 2 R 3 R 4 R 5} N + ( Compound Same as (2)). Examples of the fluoroalkyl group are the same as those for R ⁶ . Specific examples of the fluorosulfonylimide compound according to the present invention include bis (fluorosulfonyl) imide ammonium salt, bis (fluorosulfonyl) imide triethylammonium salt, (fluorosulfonyl) (trifluoromethylsulfonyl) imide ammonium salt, (fluorosulfonyl) ) (Trifluoromethylsulfonyl) imide triethylammonium salt, (fluorosulfonyl) (pentafluoroethylsulfonyl) imide ammonium salt, (fluorosulfonyl) (pentafluoroethylsulfonyl) imide triethylammonium salt, and the like. Preferably, bis (fluorosulfonyl) imide ammonium salt, bis (fluorosulfonyl) imide triethylammonium salt, (fluorosulfonyl) (trifluoromethylsulfonyl) imide ammonium salt, (fluorosulfonyl) (trifluoromethylsulfonyl) imide triethylammonium salt Is mentioned.

  The said fluorosulfonyl imide compound (1) represented by General formula (1) is made to react with an alkali metal compound, The fluoro sulfonylimide compound (alkali metal salt) represented by General formula (5) which has an alkali metal cation Is obtained (cation exchange reaction 2).

In general formula (5), R ¹ is the same as in general formula (1), and M represents an alkali metal. As the alkali metal, Li, Na, K, Rb, and Cs are preferable, Li, Na, and K are more preferable, and Li is more preferable.

Examples of the alkali metal compound to be reacted with the compound (1) include hydroxides such as LiOH, NaOH, KOH, RbOH, CsOH; Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Rb ₂ CO ₃ , Cs _2. Carbonates such as CO ₃ ; Carbonates such as LiHCO ₃ , NaHCO ₃ , KHCO ₃ , RbHCO ₃ , CsHCO ₃ ; Chlorides such as LiCl, NaCl, KCl, RbCl, CsCl; LiF, NaF, KF, RbF, CsF And the like; alkoxide compounds such as MeOLi and EtOLi; alkyllithium compounds such as EtLi and BuLi; and the like (Me represents a methyl group, Et represents an ethyl group, and Bu represents a butyl group). Among these, a compound containing lithium, sodium or potassium as an alkali metal is preferable, and more specifically, LiOH, NaOH, KOH, Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , LiCl, NaCl, KCl, LiF, NaF, and KF are preferable, LiOH, NaOH, KOH, Li ₂ CO ₃ , Na ₂ CO ₃ , and K ₂ CO ₃ are more preferable, and LiOH, NaOH, and KOH are more preferable.

  The alkali metal compound is preferably used in the range of 1 mol to 10 mol with respect to 1 mol of the fluorosulfonylimide compound (1). More preferably, it is 1 mol-5 mol, More preferably, it is 1 mol-2 mol.

  The reaction between the fluorosulfonylimide compound (1) and the alkali metal compound is preferably performed in the presence of a solvent. As the solvent, the solvent used in the synthesis reaction of the chlorosulfonylimide compound (2) or water can be used. From the viewpoint of allowing the above reaction to proceed smoothly, acetonitrile, isobutyronitrile, valeronitrile, ethyl acetate, isopropyl acetate, butyl acetate, or water are preferred. What is necessary is just to select a solvent according to the alkali metal compound to be used. Moreover, a solvent may be used individually by 1 type and may be used in combination of 2 or more type.

The reaction conditions of the fluorosulfonylimide compound (1) and the alkali metal compound are not particularly limited, and may be adjusted as appropriate according to the amount of the starting material fluorosulfonylimide compound (1) and the alkali metal compound used and the progress of the reaction. Good. For example, the reaction temperature is preferably 0 ° C to 100 ° C, more preferably 10 ° C to 80 ° C, and still more preferably 15 ° C to 40 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.3 to 10 hours, and further preferably 0.5 to 5 hours.
After completion of the reaction, the product may be purified to increase the purity. The purification method is not particularly limited, and conventionally known purification methods such as a reprecipitation method, a liquid separation extraction method, a recrystallization method, a crystallization method, and a purification method by chromatography can be used. These purification methods may be implemented individually by 1 type, and may be implemented in combination of 2 or more type.

  The fluorosulfonylimide compound represented by the general formula (5) obtained by the above production method is not limited to these, but examples thereof include lithium bis (fluorosulfonyl) imide, sodium bis (fluorosulfonyl) imide, Potassium bis (fluorosulfonyl) imide, lithium (fluorosulfonyl) (trifluoromethylsulfonyl) imide, potassium (fluorosulfonyl) (trifluoromethylsulfonyl) imide, lithium (fluorosulfonyl) (pentafluoroethylsulfonyl) imide, potassium (fluoro Sulfonyl) (pentafluoroethylsulfonyl) imide and the like, preferably lithium bis (fluorosulfonyl) imide, lithium (fluorosulfonyl) (trifluoromethylsulfonyl) It is an imide.

  The fluorosulfonylimide compound (1) (onium salt) and the fluorosulfonylimide compound (5) (alkali metal salt) obtained by the production method of the present invention are a lithium ion secondary battery, a sodium ion secondary battery, an electrolytic capacitor, an electric capacitor, It is suitably used as a material for an ion conductor constituting an electrochemical device such as a battery having a charging / discharging mechanism such as a double layer capacitor, a battery such as a primary battery, a fuel cell, a solar cell, and an electrochromic display element.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. Of course, it is possible to implement them, and they are all included in the technical scope of the present invention. In the following, “part” means “part by mass” and “%” means “mass%” unless otherwise specified.

[NMR measurement]
^{The 19} F-NMR measurement was performed using “Unity Plus-400” manufactured by Varian (internal standard substance: trifluoromethylbenzene, solvent: deuterated acetonitrile, integration number: 16 times).
The conversion rate of fluorosulfonylimide is the amount of trifluoromethylbenzene added as an internal standard substance in the chart obtained by ¹⁹ F-NMR measurement, the integrated value of the peak derived therefrom, and the target product. From the comparison with the integrated value of the peak derived, the crude yield of the fluorosulfonylimide compound (1), which is a reaction product contained in the organic layer, is determined, and the ratio of the crude yield to the chlorosulfonylimide compound (2) used as a raw material Was defined as the conversion rate.
Conversion (%) = 100 × {Rough yield of compound (1) (mol) / Amount of compound (2) charged (mol)}

  Comparative Example 1 Production of ammonium bis (fluorosulfonyl) imide

  In a reaction vessel made of 100 mL PFA (copolymer of tetrafluoroethylene and perfluoroalkoxyethylene, hereinafter the same) equipped with a stirrer, 1.07 g (5 mmol, compound (2) of bis (chlorosulfonyl) imide ) And 10 mL of valeronitrile (8.0 g, solvent) were mixed to prepare a 0.5 mol / L bis (chlorosulfonyl) imide solution. The amount of the solvent used for the compound (2) (solvent / compound (2)) was 7.4 (mass ratio).

Next, 0.69 g (12 mmol) of acidic ammonium fluoride NH ₄ F · HF was added to the bis (chlorosulfonyl) imide solution, and then a Teflon (registered trademark, the same applies hereinafter) cooler and a glass connecting tube were placed in the reaction vessel. The temperature of the attached reaction solution was raised to 80 ° C., and stirring was continued at this temperature for 4 hours.

After completion of the reaction, the reaction solution was cooled to room temperature, 10 mL of acetonitrile was added to the reaction vessel, and the reaction solution was filtered to remove solids. ¹⁹ F-NMR (solvent: deuterated acetonitrile) was measured using the obtained organic layer as a sample. In the obtained chart, the amount of trifluoromethylbenzene added as an internal standard substance, and the integrated value of the peak derived from this and the integrated value of the peak derived from the target product are included in the organic layer. The crude yield of ammonium bis (fluorosulfonyl) imide was determined (2.5 mmol, conversion 50%). When the used reaction container etc. were confirmed visually, the gloss of the glass connection pipe was lost and corrosion was confirmed. Table 1 shows the reaction conditions and the conversion rate of fluorosulfonylimide.
¹⁹ F-NMR (solvent: deuterated acetonitrile): δ 56.0

  Example 1 Preparation of ammonium bis (fluorosulfonyl) imide

  Ammonium bis (fluorosulfonyl) imide was produced in the same manner as in Comparative Example 1 except that the solvent (valeronitrile) was not used. Table 1 shows the amounts of raw materials used, the reaction conditions, and the conversion rate to fluorosulfonylimide.

Example 2 Preparation of ammonium bis (fluorosulfonyl) imide

  In a reaction vessel made of PFA having a capacity of 100 mL equipped with a stirrer, 1.07 g (5 mmol) of bis (chlorosulfonyl) imide and 0.294 g (5.5 mmol, 1.1 equivalents) of ammonium chloride were mixed and mixed at room temperature. The mixture was stirred at (25 ° C.) for 0.5 hour.

Next, 0.69 g (12 mmol) of acidic ammonium fluoride NH ₄ F · HF was added to the bis (chlorosulfonyl) imide solution, a Teflon cooler and a glass connecting tube were attached to the reaction vessel, and the temperature of the reaction solution was adjusted to 80 ° C. The temperature was raised to 0 ° C., and stirring was continued at this temperature for 4 hours. The reaction conditions and the conversion rate to fluorosulfonylimide are shown in Table 1.

Example 3, Comparative Examples 2, 4 and 6 Production of ammonium bis (fluorosulfonyl) imide Ammonium bis (fluorosulfonyl) imide was prepared in the same manner as in Comparative Example 1 except that various conditions were changed as shown in Table 1. Manufactured. Table 1 shows the amounts of raw materials used, the reaction conditions, and the conversion rate to fluorosulfonylimide.

Examples 4 to 9, Comparative Examples 3 and 5 Production of ammonium bis (fluorosulfonyl) imide Ammonium bis (fluorosulfonyl) imide was prepared in the same manner as in Example 2 except that various conditions were changed as shown in Table 1. Manufactured. Table 1 shows the amounts of raw materials used, the reaction conditions, and the conversion rate to fluorosulfonylimide.

Example 10 Preparation of ammonium bis (fluorosulfonyl) imide

  In a reaction vessel made of PFA having a capacity of 100 mL equipped with a stirrer, 1.07 g (5 mmol) of bis (chlorosulfonyl) imide and 0.5 mL of acetonitrile were mixed to prepare a 10 mol / L bis (chlorosulfonyl) imide solution. Prepared. To this, 0.27 g (5.25 mmol, 1.05 equivalent) of ammonium chloride was added and stirred at room temperature (25 ° C.) for 0.5 hour.

Next, 0.34 g (6 mmol) of acidic ammonium fluoride NH ₄ F · HF was added to this mixed solution, and then a Teflon cooler and a glass connecting tube were attached to the reaction vessel, and the ammonia gas flowed into the reaction solution ( Bubbling) started. While bubbling ammonia gas through the reaction solution (8.8 equivalents / hour. Supply amount per unit time (stoichiometric amount) to the bis (chlorosulfonyl) imide used), the temperature of the reaction solution was raised to 60 ° C. The stirring was continued for 4 hours at this temperature. The amount of ammonia gas used at this time was 35 equivalents relative to bis (chlorosulfonyl) imide. After completion of the reaction, the reaction vessel used was visually confirmed, but corrosion of the glass connecting tube could not be confirmed. The reaction conditions and the conversion rate to fluorosulfonylimide are shown in Table 1.

Comparative Example 7
Ammonium bis (fluorosulfonyl) imide was produced in the same manner as in Comparative Example 1 except that the reaction time was 8 hours. Table 1 shows the amounts of raw materials used, the reaction conditions, and the conversion rate to fluorosulfonylimide.

  In Table 1, “mass ratio” means the amount of solvent used relative to compound (2) (solvent / compound (2)), and abbreviations are valeronitrile (VN), solvent-free (neat), and acetonitrile (MeCN), respectively. , Butyl acetate (BuOAc).

  In Comparative Examples 4 to 6 using 3 equivalents or more of the compound (3) (fluorinating agent) with respect to 1 mol of the compound (2), no significant change was confirmed in the conversion rate even when the amount of the solvent used was changed. (Comparative Examples 4 to 6), the conversion decreased significantly when the amount of compound (3) used was reduced (Comparative Example 1). When the amount of compound (3) used was reduced, the conversion rate did not improve even when the reaction time was extended to 8 hours (Comparative Example 7). However, when the amount of the solvent used is 0 to 4 times the mass of the compound (2), the conversion rate can be improved to be equal to or higher than that of Comparative Examples 4 to 6 even if the amount of the compound (3) is reduced. (Example 1). This is because, in Comparative Example 1 where the amount of solvent used is large, HCl as a by-product remains in the reaction solution, whereby a salt exchange reaction proceeds between compound (3) and HCl, and compound (3) As a result of the consumption of HF and the outflow of HF from the reaction system, the conversion rate decreased, whereas in Example 1, the amount of solvent used was reduced so that it could remain in the HCl reaction system as a by-product. As a result, the progress of the salt exchange reaction was suppressed, and the amount of the compound (3) in the reaction solution was maintained, so it is considered that a high conversion rate was achieved. The effect of improving the conversion rate was confirmed in the same manner when the cation exchange reaction of the compound (2) was carried out in advance (Example 2). In addition, when the used reaction container etc. were confirmed visually after completion | finish of reaction, in the comparative examples 4-6, the gloss of the used glass connecting pipe was lost and corrosion was confirmed.

  Further, from the comparison between Examples 3 to 9 and Comparative Examples 2 to 3, when the amount of the solvent used with respect to the compound (2) is more than 4 mass times, the fluorination reaction hardly proceeds when the reaction temperature is lowered. (Comparative Example 2: 5%, Comparative Example 3: 1%) By making the amount of solvent used with respect to compound (2) in the range of 0 to 4 times by mass, the reaction can proceed even if the reaction temperature is lowered. It can be seen that a high conversion rate can be maintained (Examples 3 to 9: 73% to 94%).

From the results of Example 10, it can be seen that the conversion can be maintained even if the amount of the fluorinating agent is further reduced by carrying out the reaction under an ammonia gas stream. This is because HF generated in the reaction system reacts with NH ₃ (ammonia) to produce ammonium fluoride NH ₄ F again (NH ₃ + HF → NH ₄ F), and the amount of NH ₄ F (fluorine in the reaction system) It is surmised that the fluorination progressed efficiently because the decrease in the agent was suppressed.

Example 11
In a 100 mL PFA reaction vessel equipped with a stirrer, 1.07 g (5 mmol, compound (2)) of bis (chlorosulfonyl) imide and 4.0 g (solvent) of propyl acetate were mixed, and 1.1 mol / A bis (chlorosulfonyl) imide solution of L was prepared. The amount of the solvent used for the compound (2) (solvent / compound (2)) was 3.7 (mass ratio).

Next, 0.69 g (12 mmol, compound (3)) of acidic ammonium fluoride NH ₄ F · HF was added to the bis (chlorosulfonyl) imide solution, and then the reaction was performed by attaching a Teflon cooler and a glass connecting tube to the reaction vessel. The temperature of the solution was raised to 60 ° C., and stirring was continued at this temperature for 4 hours.

After completion of the reaction, the reaction solution was cooled to room temperature, 10 mL of acetonitrile was added to the reaction vessel, and the reaction solution was filtered to remove solids. ¹⁹ F-NMR (solvent: deuterated acetonitrile) was measured using the obtained organic layer as a sample. In the obtained chart, the amount of trifluoromethylbenzene added as an internal standard substance, and the integrated value of the peak derived from this and the integrated value of the peak derived from the target product are included in the organic layer. The crude yield of ammonium bis (fluorosulfonyl) imide was determined (4.35 mmol, conversion 87%). Table 2 shows the reaction conditions and the conversion rate of fluorosulfonylimide.
¹⁹ F-NMR (solvent: deuterated acetonitrile): δ 56.0

Example 12
In a 100 mL PFA reaction vessel equipped with a stirrer, 1.07 g (5 mmol) of bis (chlorosulfonyl) imide and 3.0 g of isopropyl acetate were mixed to give 1.5 mol / L of bis (chlorosulfonyl). An imide solution was prepared. To this, 0.294 g (5.5 mmol, 1.1 equivalents) of ammonium chloride was added and stirred at room temperature (25 ° C.) for 1 hour.

Next, 0.69 g (12 mmol) of acidic ammonium fluoride NH ₄ F · HF was added to the bis (chlorosulfonyl) imide solution, a Teflon cooler and a glass connecting tube were attached to the reaction vessel, and the temperature of the reaction solution was adjusted to 80 ° C. The temperature was raised to 0 ° C., and stirring was continued at this temperature for 4 hours. Table 2 shows the reaction conditions and the conversion rate to fluorosulfonylimide.
¹⁹ F-NMR (solvent: deuterated acetonitrile): δ 56.0

Examples 13, 15 and 17
Ammonium bis (fluorosulfonyl) imide was produced in the same manner as in Example 11 except that various conditions were changed as shown in Table 2. Table 2 shows the amounts of raw materials used, the reaction conditions, and the conversion rate to fluorosulfonylimide.

Examples 14, 16 and 18
Ammonium bis (fluorosulfonyl) imide was produced in the same manner as in Example 12 except that various conditions were changed as shown in Table 2. Table 2 shows the amounts of raw materials used, the reaction conditions, and the conversion rate to fluorosulfonylimide.

  In Table 2, “mass ratio” means the amount of solvent used (solvent / compound (2)) relative to compound (2), and abbreviations mean isopropyl acetate (iPrOAc) and butyl acetate (BuOAc).

  From the results of Table 1 and Table 2, when using 0 to 4 times mass solvent of the compound (2), the product is obtained with a high conversion rate even if the conditions such as temperature and presence / absence of cation exchange reaction are changed. It can be seen that

Claims (4)

A method for producing a fluorosulfonylimide compound represented by the following general formula (1),

(In the general formula (1), R ¹ is F, or represents a fluoroalkyl group having 1 to 6 carbon atoms, Cat1 ⁺ represents a monovalent cation represented by ^{R 2 R 3 R 4 R 5} N +, R ^{2 to} R ⁵ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms)
A compound represented by the general formula (2);

In (formula (2), R ⁶ is halogen, or represents a fluoroalkyl group having 1 to 6 carbon atoms, Cat2 ⁺ is hydrogen ion, or ^{R 2 R 3 R 4 R 5} N + represented monovalent be Represents a cation, and R ^{2 to} R ⁵ are the same as those in formula (1))
1 mol or more and 3 equivalents or less of a stoichiometric amount with respect to 1 mol of the compound represented by the general formula (2): General formula (3): NH ₄ F (HF) _p (in the general formula (3), p Represents an integer of 0 to 10),
A method for producing a fluorosulfonylimide compound, comprising reacting in the presence of a solvent represented by 0 to 4 times by mass of the compound represented by the general formula (2).   The method for producing a fluorosulfonylimide compound according to claim 1, wherein the reaction temperature is 20 ° C or higher and 75 ° C or lower.   The method for producing a fluorosulfonylimide compound according to claim 1 or 2, wherein the solvent is at least one selected from the group consisting of nitriles and carboxylic acid esters. The compound represented by the general formula (1) obtained by the method according to any one of claims 1 to 3 is reacted with an alkali metal compound. A method for producing a fluorosulfonylimide compound.

(In the general formula (5), R ¹ represents F or a fluoroalkyl group having 1 to 6 carbon atoms, and M represents an alkali metal)