JP7558752B2 - Method for producing fluorine-containing carboxylate and method for producing fluorine-containing cyclic compound - Google Patents

Description

The present invention relates to a method for producing a fluorine-containing carboxylate and a method for producing a fluorine-containing cyclic compound.

The following general formula (1):
FSO ₂ CFXCF ₂ OCF (CF ₂ Y) COF (1)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
From a fluorine-containing carboxylic acid fluoride (1) (hereinafter also referred to as "compound (1)") represented by the following formula:
The following general formula (4):
_{FSO2CFXCF2OCF ( CF2Y} ) _CO2M (4)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; and M is Na, K, Rb, or Cs.)
It is known that it is possible to produce a fluorine-containing carboxylate (4) represented by the following formula (hereinafter, also referred to as "compound (4)") (Patent Document 1, Non-Patent Document 1).

Patent Document 1 discloses a method for obtaining a fluorine-containing carboxylate (4) where X=F, Y=F and M=Na by reacting a fluorine-containing carboxylic acid fluoride (1) where X=F and Y=F with sodium carbonate in the presence of acetonitrile at room temperature for 1 hour and then at 40°C for 1 hour, followed by filtration, removal of the solvent, and distilling off the solvent under reduced pressure.
It is also disclosed that the obtained fluorine-containing carboxylate (4) can be converted into various useful fluorine compounds, and that the obtained fluorine-containing carboxylate (4) in which X=F, Y=F, and M=Na is heated to 200° C. to obtain a fluorine-containing cyclic compound (6) represented by the following general formula (6):

Non-Patent Document 1 discloses that a fluorine-containing carboxylate (4) in which X=F, Y=F and M=Na is produced by reacting a fluorine-containing carboxylic acid fluoride (1) in which X=F and Y=F with sodium carbonate in the presence of tetraethylene glycol dimethyl ether for 3 hours while maintaining the temperature at 30° C. or lower and then for 1 hour at 40° C.
It is also disclosed that the obtained fluorine-containing carboxylate (4) can be converted into various useful fluorine compounds, and that the fluorine-containing cyclic compound (6) represented by the above general formula (6) can be obtained by heating the obtained fluorine-containing carboxylate (4) in which X=F, Y=F, and M=Na to 160° C.

International Publication No. 2002/062749

Journal of Fluorine Chemistry, Vol. 127 (2006), pp. 1087-1095

In Patent Document 1, a fluorine-containing carboxylic acid fluoride (1) where X=F and Y=F is reacted with sodium carbonate in an acetonitrile solvent at room temperature for 1 hour and at 40°C for 1 hour to obtain a fluorine-containing carboxylate (4) where X=F, Y=F and M=Na. However, in a situation where the external environment is low temperature, it is necessary to heat the reaction solution to an appropriate temperature in order to obtain similar reaction results. Therefore, there is a demand for a production method that has high reactivity and can provide a stable high yield even under low temperature conditions.

In Non-Patent Document 1, a fluorine-containing carboxylic acid fluoride (1) where X=F and Y=F is reacted with sodium carbonate in a tetraethylene glycol dimethyl ether solvent for 3 hours while maintaining the temperature at 30°C or less, and then for 1 hour at 40°C to obtain a fluorine-containing carboxylate (4) where X=F, Y=F, and M=Na. However, cooling may be required to maintain the temperature at 30°C or less, and heating may be required to reach 40°C after cooling, which may make the operation complicated. Therefore, there is a demand for a production method that has high reactivity under low-temperature conditions and can provide a stable high yield without complicated operations.

The present invention has been made in consideration of the above circumstances, and aims to provide a method for producing a fluorine-containing carboxylate (4) that has high reactivity even under low-temperature conditions and can be converted into various fluorine compounds in a stable and high yield. Furthermore, the present invention aims to provide a method for producing a fluorine-containing cyclic compound (5) in a high yield even under low-temperature conditions by using the fluorine-containing carboxylate (4) thus produced.

As a result of intensive research into solving the above-mentioned problems, the present inventors have found that in a method of reacting a fluorinated carboxylic acid fluoride (1) with a specific alkali metal carbonate (2) (hereinafter also referred to as "compound (2)") in the presence of a specific ether compound (3) (hereinafter also referred to as "compound (3)"), the above-mentioned object can be achieved by setting the ratio (β/α) of the substance amount (β) of compound (2) to the substance amount (α) of compound (1) and the ratio (δ/γ) of the mass (δ) of compound (3) to the mass (γ) of compound (1) within specific ranges, and have thus completed the present invention.
Furthermore, the present inventors have found that the above object can be achieved by heat-treating the obtained fluorinated carboxylate (4) to produce a fluorinated cyclic compound (5) (hereinafter also referred to as "compound (5)"), and have thus completed the present invention.

（式中、Ｘは、フッ素原子、塩素原子、又はトリフルオロメチル基であり；Ｙは、フッ素原子、塩素原子、臭素原子、又はヨウ素原子である。）
で表される含フッ素環状化合物（５）の製造方法。 That is, the present invention is as follows.
[1]
The following general formula (4):
_{FSO2CFXCF2OCF ( CF2Y} ) _CO2M (4)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; and M is K, Rb, or Cs.)
The present invention relates to a method for producing a fluorine-containing carboxylate (4) represented by the following formula:
The following general formula (1):
FSO ₂ CFXCF ₂ OCF (CF ₂ Y) COF (1)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
A fluorine-containing carboxylic acid fluoride (1) represented by the formula:
The following general formula (2):
_M2CO3 ( ₂ )
(In the formula, M is K, Rb, or Cs.)
and an alkali metal carbonate (2) represented by
The following general formula (3):
R ¹ (OR ² ) _p OR ³ (3)
(In the formula, R ¹ , R ² , and R ³ may be the same or different, and each represents an aliphatic or aromatic hydrocarbon group which may be substituted or unsubstituted and has 1 to 10 carbon atoms; and p is an integer from 2 to 10.)
The reaction is carried out in the presence of an ether-based compound (3) represented by the formula:
the ratio (β/α) of the amount of substance (β) of the compound (2) to the amount of substance (α) of the compound (1) is 2 or less;
A method for producing a fluorine-containing carboxylate (4), characterized in that a ratio (δ/γ) of the mass (δ) of the compound (3) to the mass (γ) of the compound (1) exceeds 0.55.
[2]
The method for producing a fluorine-containing carboxylate (4) according to [1], wherein the ether compound (3) is at least one selected from the group consisting of diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, and dipropylene glycol dimethyl ether.
[3]
Obtaining a fluorine-containing carboxylate (4) by the method for producing a fluorine-containing carboxylate (4) according to [1] or [2];
heat-treating the obtained fluorine-containing carboxylate (4) ;
Characterized in that it comprises
The following general formula (5):

(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
A method for producing a fluorine-containing cyclic compound (5) represented by the following formula:

According to the present invention, it is possible to produce a fluorine-containing carboxylate (4) that has high reactivity even under low-temperature conditions and can be converted into various fluorine compounds in a stable and high yield. Furthermore, by using the fluorine-containing carboxylate (4) thus produced, it is possible to produce a fluorine-containing cyclic compound (5) in a high yield even under low-temperature conditions.

The following describes in detail the form for carrying out the present invention (hereinafter, referred to as the "present embodiment"). However, the present invention is not limited to the present embodiment below, and can be carried out in various modifications within the scope of the gist of the present invention.

The method for producing the fluorinated carboxylate (4) of the present embodiment includes the following steps:
The following general formula (4):
_{FSO2CFXCF2OCF ( CF2Y} ) _CO2M (4)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; and M is K, Rb, or Cs.)
The present invention relates to a method for producing a fluorine-containing carboxylate (4) represented by the following formula:
The following general formula (1):
FSO ₂ CFXCF ₂ OCF (CF ₂ Y) COF (1)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
A fluorine-containing carboxylic acid fluoride (1) represented by the formula:
The following general formula (2):
_M2CO3 ( ₂ )
(In the formula, M is K, Rb, or Cs.)
and an alkali metal carbonate (2) represented by
The following general formula (3):
R ¹ (OR ² ) _p OR ³ (3)
(In the formula, R ¹ , R ² , and R ³ may be the same or different, and each represents an aliphatic or aromatic hydrocarbon group which may be substituted or unsubstituted and has 1 to 10 carbon atoms; and p is an integer from 2 to 10.)
The reaction is carried out in the presence of an ether-based compound (3) represented by the formula:
the ratio (β/α) of the amount of substance (β) of the compound (2) to the amount of substance (α) of the compound (1) is 2 or less;
The ratio (δ/γ) of the mass (δ) of the compound (3) to the mass (γ) of the compound (1) is greater than 0.55.

The following provides details about compounds (1), (2), and (3), as well as the reaction conditions for producing compound (4) from compound (1).

<Fluorine-containing carboxylic acid fluoride (1) (compound (1))>
The fluorine-containing carboxylic acid fluoride (1) is represented by the following general formula (1):
FSO ₂ CFXCF ₂ OCF (CF ₂ Y) COF (1)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
It is expressed as:
The compound (1) may be used alone or in combination of two or more kinds.

As X, a fluorine atom or a trifluoromethyl group is preferable because they are easily available or produced and tend to be economically advantageous, and from the same viewpoint, a fluorine atom is more preferable.
As Y, a fluorine atom or a chlorine atom is preferable since they are easily available or produced and tend to be economically superior, and from the same viewpoint, a fluorine atom is more preferable.
A particularly preferred combination of X and Y is that both are fluorine atoms (X=F, Y=F).

The method for producing compound (1) is not particularly limited, and compound (1) can be produced by a conventionally known method. For example, compound (1) in which X=F and Y=F can be produced by the method described in International Publication No. 1998/43952. Compound (1) can also be purchased from, for example, Synquest Laboratories.

<Alkali Metal Carbonate (2) (Compound (2))>
The alkali metal carbonate (2) is represented by the following general formula (2):
_M2CO3 ( ₂ )
(In the formula, M is K, Rb, or Cs.)
It is expressed as:
The compound (2) may be used alone or in combination of two or more kinds.

As M, K or Cs is preferred because they are easily available and tend to be economical, and K is more preferred from the same perspective.

Compound (2) having a reduced water content can be used as necessary. In particular, when compound (5) is produced in a single reaction from compound (1) via compound (4), it is preferable to use compound (2) having a reduced water content, since side reactions can be suppressed and the yield of compound (5) tends to be increased.
The method for reducing the water content of compound (2) is not particularly limited as long as it is a commonly available method, and examples of the method include a method of heating, a method of heating under vacuum, and a method of heating under a dry gas flow.
The heating temperature is not particularly limited as long as it is a temperature that can reduce the water content of compound (2), but since there is a tendency to suppress the decomposition of compound (2), it is preferably 600° C. or less. Since excessive heating is suppressed and there is a tendency to be more economical, it is more preferably 300° C. or less, and from the same viewpoint, it is even more preferably 250° C. or less, and particularly preferably 200° C. or less. In addition, since there is a tendency to promote the reduction of the water content, it is preferably 100° C. or more, more preferably 120° C. or more, and even more preferably 150° C. or more.
The dry gas is not particularly limited as long as it is a commonly used dry gas, and examples of the dry gas include dry air and dry nitrogen.

<Ether Compound (3) (Compound (3))>
The ether-based compound (3) is represented by the following general formula (3):
R ¹ (OR ² ) _p OR ³ (3)
(In the formula, R ¹ , R ² , and R ³ may be the same or different, and each represents an aliphatic or aromatic hydrocarbon group which may be substituted or unsubstituted and has 1 to 10 carbon atoms; and p is an integer from 2 to 10.)
The compound (3) may be used alone or in combination of two or more kinds.

In the compound (3), R ¹ , R ² and R ³ are each a substituted or unsubstituted aliphatic hydrocarbon group or aromatic hydrocarbon group.
The substituent is not particularly limited, but examples thereof include halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms, nitrile groups (-CN), ether groups (-O-), carbonate groups (-OCO ₂ -), ester groups (-CO ₂ -), carbonyl groups (-CO-), sulfide groups (-S-), sulfoxide groups (-SO-), sulfone groups (-SO ₂ -), and urethane groups (-NHCO ₂ -).
From the viewpoint of increasing the reactivity between compound (1) and compound (2), R ¹ , R ² , and R ³ are preferably a substituted or unsubstituted aliphatic hydrocarbon group, and more preferably an unsubstituted aliphatic hydrocarbon group because they are easily available and tend to be economically superior.

R ¹ , R ² and R ³ in the compound (3) each have 1 to 10 carbon atoms.
Since the reactivity of compound (1) and compound (2) tends to be increased, the carbon numbers of R ¹ and R ³ are preferably 6 or less, and from the same viewpoint, more preferably 4 or less. Since the stability of compound (2) tends to be increased, the carbon numbers of R ¹ and R ³ are further preferably 2 or less. From the same viewpoint, it is particularly preferable that the carbon number of R ¹ and R ³ is 1.
Since the reactivity of compound (1) and compound (2) tends to be increased, the carbon number of ^R2 is preferably 2 or more. Since the reactivity of compound (1) and compound (2) tends to be increased, the carbon number of ^R2 is preferably 6 or less, and from the same viewpoint, it is more preferably 4 or less. Since it tends to be easily available and has excellent economical properties, it is even more preferable that the carbon number of ^R2 is 3 or less. Since the reactivity of compound (1) and compound (2) tends to be increased and has excellent economical properties, it is particularly preferable that the carbon number of ^R2 is 2.

In compound (3), p is an integer from 2 to 10. Since compound (3) is easily available and tends to be economical, p is 10 or less, preferably 6 or less, and more preferably 4 or less. Since compound (1) and compound (2) tend to have high reactivity, p is 2 or more.

Examples of compound (3) include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, and dipropylene glycol dimethyl ether.

Since the reactivity of compound (1) and compound (2) tends to be increased, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, and tetraethylene glycol dimethyl ether are preferred, and from the same viewpoint, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether are more preferred, and diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether are even more preferred.

Compound (3) having a reduced water content can be used as necessary. In particular, when compound (5) is produced in a single reaction from compound (1) via compound (4), it is preferable to use compound (3) having a reduced water content, since side reactions can be suppressed and the yield of compound (5) tends to be increased.
Compound (3) having a low water content can be purchased, or a method for reducing the water content of compound (3) can be used. The method for reducing the water content of compound (3) is not particularly limited as long as it is a commonly available method, and examples thereof include a method using a dehydrating agent and a distillation method.
The dehydrating agent is not particularly limited as long as it is a commonly used dehydrating agent, and examples thereof include sodium hydride, magnesium sulfate, sodium sulfate, calcium sulfate, calcium chloride, zinc chloride, calcium oxide, magnesium oxide, diphosphorus pentoxide, activated alumina, silica gel, and molecular sieves. When a dehydrating agent is used, a compound (3) containing a dehydrating agent may be used as long as it does not affect the reaction between compound (1) and compound (2), or a compound (3) that does not contain a dehydrating agent after filtration or the like may be used.

<Ratio (β/α) of the amount of substance (β) of compound (2) to the amount of substance (α) of compound (1)>
The ratio (β/α) of the amount of substance (β) of compound (2) to the amount of substance (α) of compound (1) tends to increase the yield of compound (4) and tends to make the method for producing compound (4) more economical, and is therefore preferably 2 or less, more preferably 1.8 or less, and more preferably 1.5 or less.

The ratio (β/α) of the amount of substance (β) of compound (2) to the amount of substance (α) of compound (1) is preferably 0.5 or more, and more preferably 0.8 or more, since the yield of compound (4) tends to increase and the method for producing compound (4) tends to be more economical. It is even more preferable that the ratio is 1 or more, since it tends to prevent unreacted compound (1) from remaining.

<Ratio (δ/γ) of the mass (δ) of compound (3) to the mass (γ) of compound (1)>
The ratio (δ/γ) of the mass (δ) of compound (3) to the mass (γ) of compound (1) exceeds 0.55 because the reactivity between compound (1) and compound (2) tends to increase. From the same viewpoint, δ/γ is preferably 0.8 or more, and more preferably δ/γ is 1 or more.

The upper limit of the ratio (δ/γ) of the mass (δ) of compound (3) to the mass (γ) of compound (1) is not particularly limited, but since the amount of compound (3) used is reduced and the method for producing compound (4) tends to be more economical, it is preferable that δ/γ is 10 or less, and from the same viewpoint, it is more preferable that δ/γ is 7 or less, and even more preferable that δ/γ is 5 or less.

<Reaction of Compound (1) and Compound (2)>
The reaction temperature of compound (1) and compound (2) is not particularly limited as long as it is a reaction temperature that is generally used, but since the reactivity of compound (1) and compound (2) tends to be increased, the reaction temperature is preferably −40° C. or higher, and more preferably −20° C. or higher. From the same viewpoint and also because the reaction temperature tends to be economically advantageous when adjusting the temperature industrially, the reaction temperature is further preferably 0° C. or higher.
The upper limit of the reaction temperature between compound (1) and compound (2) is not particularly limited, but is preferably 100° C. or lower, more preferably 60° C. or lower, and even more preferably 40° C. or lower, since the yield of compound (4) tends to increase and the economic efficiency of the method for producing compound (4) tends to be excellent.
The reaction temperature of the compound (1) and the compound (2) does not need to be constant so long as it is within the above range, and may be changed during the reaction.

The reaction time between compound (1) and compound (2) is not particularly limited as long as it is within the range generally used, but is preferably 10 minutes or more, and more preferably 0.5 hours or more, because this increases the stability of the yield of compound (4). Avoiding an excessive reaction time tends to result in a more economical production method, so it is preferably 100 hours or less, and from the same viewpoint, it is more preferably 50 hours or less, and even more preferably 20 hours or less.

The reaction pressure of compound (1) and compound (2) is not particularly limited as long as it is within the range of normal use, and the reaction is usually carried out under atmospheric pressure. However, depending on the type of compound (1) and/or compound (3), the vapor pressure at standard conditions is low, so when compound (1) and/or compound (3) are liquefied and not reused, pressurization at atmospheric pressure or higher is an effective means. When compound (1) and/or compound (3) are liquefied and reused, reduced pressure below atmospheric pressure may be used.
The pressure for the reaction of compound (1) and compound (2) does not need to be constant so long as it is within the above range, and may be changed during the reaction.

The atmosphere for the reaction of compound (1) and compound (2) is not particularly limited as long as it is a commonly used atmosphere, and usually, air atmosphere, nitrogen atmosphere, argon atmosphere, etc. are used. Among these, nitrogen atmosphere and argon atmosphere are preferred because they tend to produce compound (4) more safely. In addition, nitrogen atmosphere is more preferred because they tend to be a more economical production method.
The reaction atmosphere may be used alone or in combination of a plurality of reaction atmospheres.

The order in which compounds (1), (2), and (3) are added is not particularly limited, but since the reaction between compound (1) and compound (2) is an exothermic reaction and side reactions tend to be suppressed, particularly when the amounts of compounds (1), (2), and (3) used are large, preferred methods include gradually adding a mixture of compound (1) and compound (3) to compound (2), gradually adding compound (2) to a mixture of compound (1) and compound (3), gradually adding a mixture of compound (2) and compound (3) to compound (1), and gradually adding compound (1) to a mixture of compound (2) and compound (3).

（式中、Ｘは、フッ素原子、塩素原子、又はトリフルオロメチル基であり；Ｙは、フッ素原子、塩素原子、臭素原子、又はヨウ素原子である。）
で表される含フッ素環状化合物（５）の製造方法は、
上述の本実施形態の含フッ素カルボン酸塩（４）の製造方法により得られる含フッ素カルボン酸塩（４）を加熱処理することを特徴とする。 In this embodiment, the following general formula (5):

(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
The method for producing the fluorine-containing cyclic compound (5) represented by the following formula (5) is
The method is characterized in that the fluorine-containing carboxylate (4) obtained by the above-mentioned method for producing the fluorine-containing carboxylate (4) of the present embodiment is subjected to a heat treatment.

The fluorine-containing cyclic compound (5) can be produced by using the compound (4) obtained by the production method of this embodiment described above.
For example, compound (5) can be produced by a method in which compound (4) is extracted from the reaction solution produced during the production of compound (4) and the resulting compound (4) is heated as is or after addition of a compound that promotes the reaction (e.g., an ether-based compound such as compound (3)), or by a method in which the reaction solution produced during the production of compound (4) is heated as is. Among these, the method of producing compound (5) by directly heating the reaction solution produced during the production of compound (4) is preferred, since it enables compound (5) to be produced from compound (1) in a single reaction without complicated operations.

The term "heat treatment" as used herein means exposing compound (4) to a temperature equal to or higher than the reaction temperature during the production of compound (4). In particular, it is preferable to make the temperature of the heat treatment equal to the reaction temperature during the production of compound (4), since this does not require a complicated operation for changing the temperature conditions, and the stability of the reaction time of compound (4) tends to be improved.
Specifically, the temperature for the heat treatment is not particularly limited as long as it is equal to or higher than the reaction temperature during the production of compound (4), but since the reactivity of compound (4) tends to increase, the temperature is preferably 40° C. or higher, more preferably 50° C. or higher, and even more preferably 60° C. or higher. In addition, since side reactions tend to be suppressed, the temperature for the heat treatment is preferably 160° C. or lower, more preferably 120° C. or lower, and even more preferably 80° C. or lower.
The temperature for the heat treatment does not need to be constant as long as it is within the above range, and may be changed during the treatment.

The time for the heat treatment is not particularly limited as long as it is within the range generally used, but since the stability of the yield of compound (5) is further increased, it is preferably 0.5 hours or more, and more preferably 1 hour or more. Since avoiding an excessive reaction time tends to result in a more economical production method, it is preferably 100 hours or less, and from the same viewpoint, it is more preferably 50 hours or less, and even more preferably 20 hours or less.

The pressure for the heat treatment is not particularly limited as long as it is within the range usually used, and is usually carried out under atmospheric pressure. However, depending on the type of compound (3), the vapor pressure at standard conditions is low, so when compound (3) is liquefied and not reused, pressurization at atmospheric pressure or higher is an effective means. When compound (3) is liquefied and reused, reduced pressure below atmospheric pressure may be used. When compound (5) is obtained by evaporating, removing it from the reaction solution, and liquefying it, reduced pressure may be used.
The pressure for the heat treatment does not need to be constant as long as it is within the above range, and may be changed during the treatment.

The atmosphere for the heat treatment is not particularly limited as long as it is a commonly used atmosphere, and usually, air atmosphere, nitrogen atmosphere, argon atmosphere, etc. are used. Among these, nitrogen atmosphere and argon atmosphere are preferred because they tend to produce compound (5) more safely. In addition, nitrogen atmosphere is more preferred because they tend to be a more economical production method.
The reaction atmosphere may be used alone or in combination of a plurality of reaction atmospheres.

As described above, the present invention makes it possible to produce a fluorine-containing carboxylate (4) that has high reactivity even under low-temperature conditions and can be converted into various fluorine compounds in a stable and high yield. Furthermore, by using the fluorine-containing carboxylate (4) thus produced, a fluorine-containing cyclic compound (5) can be produced in a high yield even at a temperature lower than conventionally.

The following are examples that specifically explain this embodiment. The present invention is not limited to the following examples as long as they do not depart from the gist of the invention.

The analytical methods used in the examples and comparative examples are as follows:

<Nuclear Magnetic Resonance Analysis (NMR): Molecular Structure Analysis by ¹⁹ F-NMR>
The products obtained in the examples and comparative examples were subjected to molecular structure analysis using ¹⁹ F-NMR under the following measurement conditions.
[Measurement conditions]
Measurement device: JNM-ECZ400S nuclear magnetic resonance device (manufactured by JEOL Ltd.)
Observed nucleus: ^19F
Solvent: deuterated chloroform Standard substance: tetramethylsilane (0.00 ppm)
Observation frequency: 400MHz ( ^1H )
Pulse width: 6.5 μsec Waiting time: 2 sec Number of integrations: 16

The raw materials used in the examples and comparative examples are listed below.

(Fluorine-containing carboxylic acid fluoride (1) (compound (1))
According to the method described in WO 1998/43952, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F was produced and further purified by distillation to obtain CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F with a purity of >99%.

(Alkali Metal Carbonate (2) (Compound (2))
・Potassium carbonate (Fujifilm Wako Pure Chemical Industries, special grade reagent)
Rubidium carbonate (Aldrich, purity 99%)
Cesium carbonate (Aldrich, purity 99%)

(Ether Compound (3) (Compound (3))
Diethylene glycol dimethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd., prepared by adding dried molecular sieve 3A 1/16 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), dehydrating, and removing the molecular sieve 3A 1/16)
Tetraethylene glycol dimethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd., prepared by adding dried molecular sieve 3A 1/16 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), dehydrating, and removing the molecular sieve 3A 1/16)

(others)
・Sodium carbonate (Fujifilm Wako Pure Chemical Industries, special grade reagent)
- Acetone (Fujifilm Wako Pure Chemical Industries, special grade reagent)
- Benzotrifluoride (Tokyo Chemical Industry Co., Ltd.)
・1,2-dimethoxyethane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., special grade reagent)

[Example 1]
A stirrer and potassium carbonate (0.41 g, 2.98 mmol) were placed in a test tube (Radley Discovery Technologies, RP98059, RP98062), and placed in a heating/cooling stirrer (Tokyo Rikakikai Co., Ltd., PPM-5512 type, cooling water was circulated from the outside when cooling), dried at 150° C. under vacuum for 5 hours, returned to room temperature, and placed in a nitrogen atmosphere. The heating/cooling stirrer was set to 0° C., and tetraethylene glycol dimethyl ether (1.00 g) was added to the test tube and stirred. Then, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F (1.00 g, 2.89 mmol) was added dropwise over 10 minutes. After stirring for another 2 hours, acetone (4.00 g) and benzotrifluoride (0.10 g) were added for analysis and stirred. The reaction mixture obtained was filtered, and the filtrate was analyzed by ^19F -NMR. As a result of the analysis, it was found that potassium fluorinated carboxylate (7) represented by the following general formula (7) was produced (amount produced: 1.07 g, mass of product: 2.79 mmol, production rate: 96.6%). In the analysis, the amount of potassium fluorinated carboxylate (7) produced was calculated from the mass of benzotrifluoride, the integral value of _CF3 of benzotrifluoride, and the integral value of _CF3 of potassium fluorinated carboxylate (7).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.
_KO2CCF ( _{CF3 ) OCF2CF2SO2F} ( ₇ )
¹⁹ F-NMR: δ (ppm) 43.22 (1F), -80.32 (1F), -84.02 (3F), -83.52 (1F), -113.04 (2F), -129.05 (1F)

[Example 2]
Except for changing the amount of potassium carbonate used to 0.60 g (4.33 mmol), a fluorinated carboxylate potassium salt (7) was produced in the same manner as in Example 1. As a result of analysis, it was found that a fluorinated carboxylate potassium salt (7) was produced (amount produced: 1.06 g, product mass: 2.78 mmol, production rate: 96.1%).
In this embodiment, β/α was 1.5 and γ/δ was 1.0.

[Example 3]
Except for changing the amount of tetraethylene glycol dimethyl ether used to 5.00 g, a fluorinated potassium carboxylate (7) was produced in the same manner as in Example 1. As a result of analysis, it was found that a fluorinated potassium carboxylate (7) was produced (amount produced: 1.05 g, product mass: 2.75 mmol, production rate: 95.2%).
In this embodiment, β/α was 1.0 and γ/δ was 5.0.

[Example 4]
A fluorinated potassium carboxylate ( ₇ ) was produced in the same manner as in Example 1, except that the temperature of the heating/cooling stirrer was set to 40° C. and the stirring time after the dropwise addition of _{CF 3 CF} (COF)OCF 2 CF 2 SO 2 F over 10 minutes was set to 0.5 hours. Analysis showed that a fluorinated potassium carboxylate (7) was produced (amount produced: 1.05 g, product mass: 2.74 mmol, production rate: 94.7%).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Example 5]
Except for using rubidium carbonate (0.69 g, 2.98 mmol) instead of potassium carbonate and changing the stirring time after _CF3CF ( _COF ) _OCF2CF2SO2F to 1 hour, a _{fluorine-containing rubidium carboxylate (RbO2CCF ( CF3} ) _OCF2CF2SO2F ) was produced in the same manner as in Example _1. Analysis showed that a fluorine _- containing rubidium carboxylate was produced (amount produced: 1.19 g, product mass: 2.77 mmol, production rate: 95.8%).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Example 6]
Except for using cesium carbonate (0.97 g, 2.98 mmol) instead of potassium carbonate and changing the stirring time after dropwise addition of _CF3CF ( _COF ) _OCF2CF2SO2F over 10 minutes to 1 hour, a fluorine-containing cesium carboxylate ( _CsO2CCF ( _CF3 ) _OCF2CF2SO2F ) was produced in the same _manner as in Example _1. Analysis showed that a fluorine-containing cesium carboxylate was produced (amount produced: 1.32 g, product mass: _2.78 mmol, production rate: 96.2%).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Example 7]
Except for using diethylene glycol dimethyl ether (1.00 g) instead of tetraethylene glycol dimethyl ether, a fluorinated potassium carboxylate (7) was produced in the same manner as in Example 1. Analysis revealed that a fluorinated potassium carboxylate (7) was produced (amount produced: 1.06 g, product mass: 2.76 mmol, production rate: 95.6%).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Comparative Example 1]
Except for using sodium carbonate (0.32 g, _2.98 mmol) instead of potassium carbonate, a fluorinated carboxylate sodium salt ( _NaO2CCF ( _CF3 ) _OCF2CF2SO2F ) was produced _in the same manner as in Example 1. Analysis showed that a fluorinated carboxylate sodium salt was produced (amount produced: 0.13 g, product mass: 0.35 mmol, production rate: 12.1%).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Comparative Example 2]
Except for changing the amount of sodium carbonate used to 0.46 g (4.33 mmol) and the amount of tetraethylene glycol dimethyl ether used to 5.00 g, a fluorinated carboxylate sodium salt was produced in the same manner as in Comparative Example 1. Analysis showed that a fluorinated carboxylate sodium salt was produced (amount produced: 0.21 g, product mass: 0.59 mmol, production rate: 20.3%).
In this embodiment, β/α was 1.5 and γ/δ was 5.0.

[Comparative Example 3]
The following experiment was carried out with reference to Example 1 of Patent Document 1.
A stirrer and sodium carbonate (0.92 g, 8.67 mmol) were placed in a test tube (Radley Discovery Technologies, RP98059, RP98062), which was then placed in a heating/cooling stirrer (Tokyo Rikakikai Co., Ltd., PPM-5512 type, cooling water was circulated from the outside when cooling), dried under vacuum at 150° C. for 5 hours, returned to room temperature, and placed in a nitrogen atmosphere. The heating/cooling stirrer was set to 30° C., and acetonitrile (3.38 g) was added to the test tube and stirred. Subsequently, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F (3.00 g, 8.67 mmol) was added dropwise over 10 minutes, and the mixture was stirred for 1 hour. The heating/cooling stirrer was set to 40° C., and the mixture was further stirred for 1 hour. After returning to room temperature, benzotrifluoride (0.30 g) was added and stirred for analysis. The resulting reaction mixture was filtered, and the filtrate was analyzed by ¹⁹ F-NMR. The analysis showed that a fluorine-containing carboxylate sodium salt was produced (production amount: 2.61 g, product mass: 7.13 mmol, production rate: 82.3%).
In this embodiment, β/α was 1.0 and γ/δ was 1.1.

[Comparative Example 4]
With reference to Non-Patent Document 1, the following procedure was carried out.
A stirrer and sodium carbonate (1.06 g, 9.96 mmol) were placed in a test tube (Radley Discovery Technologies, RP98059, RP98062), placed in a heating/cooling stirrer (Tokyo Rikakikai Co., Ltd., PPM-5512 type, cooling water was circulated from the outside when cooling), dried under vacuum at 150° C. for 5 hours, returned to room temperature, and placed in a nitrogen atmosphere. The heating/cooling stirrer was set to 30° C., and tetraethylene glycol dimethyl ether (3.24 g) was added to the test tube and stirred. Subsequently, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F (3.00 g, 8.67 mmol) was added dropwise over 10 minutes, and stirred for 3 hours. The heating/cooling stirrer was set to 40° C., and stirred for another 1 hour. After returning to room temperature, benzotrifluoride (0.30 g) and acetone (12.00 g) were added and stirred for analysis. The resulting reaction mixture was filtered, and the filtrate was analyzed by ¹⁹ F-NMR. The analysis showed that a fluorine-containing carboxylate sodium salt was produced (production amount: 2.37 g, product mass: 6.48 mmol, production rate: 74.7%).
In this embodiment, β/α was 1.1, and γ/δ was 1.1.

As described above, in the examples, it was possible to produce a fluorine-containing carboxylate (4) that has high reactivity even under low-temperature conditions and can be converted into various fluorine compounds in a stable and high yield.

^１９Ｆ－ＮＭＲ：δ（ｐｐｍ）－１２４．７（１Ｆ）、－１２０．６（１Ｆ）、－１１５．４（１Ｆ）、－９０．１（１Ｆ）、－８０．５（３Ｆ）、－７８．０（１Ｆ） [Example 8]
A stirrer and potassium carbonate (0.41 g, 2.98 mmol) were placed in a test tube (Radley Discovery Technologies, RP98059, RP98062), which was then placed in a heating/cooling stirrer (Tokyo Rikakikai Co., Ltd., PPM-5512 type, cooling water was circulated from the outside when cooling), dried under vacuum at 150° C. for 5 hours, returned to room temperature, and placed in a nitrogen atmosphere. The heating/cooling stirrer was set to 0° C., and tetraethylene glycol dimethyl ether (1.00 g) was added to the test tube and stirred. Then, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F (1.00 g, 2.89 mmol) was added dropwise over 10 minutes. After stirring for another 2 hours, the heating/cooling stirrer was set to 60° C., and stirring was continued for 2 hours. After cooling to room temperature, acetone (4.00 g) and benzotrifluoride (0.10 g) were added and stirred for analysis. The resulting reaction mixture was filtered, and the filtrate was analyzed by ¹⁹ F-NMR. As a result of the analysis, it was found that a fluorine-containing cyclic compound (8) represented by the following general formula (8) was produced (amount produced: 0.78 g, product mass: 2.77 mmol, production rate: 95.8%). In the analysis, the amount of fluorine-containing cyclic compound (8) produced was calculated from the mass of benzotrifluoride, the integral value of _CF3 of benzotrifluoride, and the integral value of _CF3 of fluorine-containing cyclic compound (8).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

¹⁹ F-NMR: δ (ppm) -124.7 (1F), -120.6 (1F), -115.4 (1F), -90.1 (1F), -80.5 (3F), -78.0 (1F)

[Example 9]
A stirrer and potassium carbonate (0.41 g, 2.98 mmol) were placed in a test tube (Radley Discovery Technologies, RP98059, RP98062), which was then placed in a heating/cooling stirrer (Tokyo Rikakikai Co., Ltd., PPM-5512 type, cooling water was circulated from the outside when cooling), dried under vacuum at 150° C. for 5 hours, returned to room temperature, and placed in a nitrogen atmosphere. The heating/cooling stirrer was set to 0° C., and tetraethylene glycol dimethyl ether (1.00 g) was added to the test tube and stirred. Then, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F (1.00 g, 2.89 mmol) was added dropwise over 10 minutes. After stirring for another 2 hours, the heating/cooling stirrer was set to 80° C. and stirred for 1 hour. After cooling to room temperature, acetone (4.00 g) and benzotrifluoride (0.10 g) were added and stirred for analysis. The resulting reaction mixture was filtered, and the filtrate was analyzed by ¹⁹ F-NMR. The analysis showed that fluorine-containing cyclic compound (8) was produced (amount produced: 0.78 g, product mass: 2.77 mmol, production rate: 96.0%). In the analysis, the amount of fluorine-containing cyclic compound (8) produced was calculated from the mass of benzotrifluoride, the integral value of _CF3 of benzotrifluoride, and the integral value of _CF3 of fluorine-containing cyclic compound (8).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Example 10]
A stirrer and potassium carbonate (0.41 g, 2.98 mmol) were placed in a test tube (Radley Discovery Technologies, RP98059, RP98062), which was then placed in a heating/cooling stirrer (Tokyo Rikakikai Co., Ltd., PPM-5512 model, cooling water was circulated from the outside when cooling), dried under vacuum at 150° C. for 5 hours, returned to room temperature, and placed in a nitrogen atmosphere. The heating/cooling stirrer was set to 60° C., and tetraethylene glycol dimethyl ether (1.00 g) was added to the test tube and stirred. Then, CF ₃ CF(COF)OCF ₂ CF ₂ SO ₂ F (1.00 g, 2.89 mmol) was added dropwise over 10 minutes. After stirring for another 2 hours, the mixture was cooled to room temperature, and acetone (4.00 g) and benzotrifluoride (0.10 g) were added for analysis, followed by stirring. The resulting reaction mixture was filtered, and the filtrate was analyzed by ¹⁹ F-NMR. As a result of the analysis, it was found that fluorine-containing cyclic compound (8) was produced (amount produced: 0.77 g, product mass: 2.74 mmol, production rate: 94.8%). In the analysis, the amount of fluorine-containing cyclic compound (8) produced was calculated from the masses of benzotrifluoride and fluorine-containing cyclic compound (8), and the integral values of _CF3 of benzotrifluoride and _CF3 of fluorine-containing cyclic compound (8).
In this embodiment, β/α was 1.0 and γ/δ was 1.0.

[Example 11]
Potassium carbonate (142.8 g, 1.03 mol) previously dried at 150 ° C. under vacuum for 5 hours was placed in a 1 L double-tube reaction vessel (Asahi Seisakusho Co., Ltd.) equipped with a mechanical stirrer (Tokyo Rikakikai Co., Ltd., ZZ-1020) with a stirring blade, a dropping funnel, a Liebig cooling tube with a receiver, and a thermometer protection tube with a temperature sensor, and then tetraethylene glycol dimethyl ether (336.3 g) was added and stirred after making a nitrogen atmosphere. A circulating thermostatic bath (LAUDA, RE1050G) was connected to the 1 L double-tube reaction vessel, set to 0 ° C., and waited until the temperature of the reaction vessel contents stabilized. Then, CF ₃ CF (COF) OCF ₂ CF ₂ SO ₂ F (311.4 g, 0.90 mol) was added dropwise over 1 hour. A cooling water circulation device (LTC-450a, manufactured by AS ONE CORPORATION) set to 0°C was connected to the Liebig condenser, and the receiver was cooled with ice. The temperature of the circulating thermostatic bath was then set to 120°C, at which point volatile components gradually began to distill off, and a liquid (244.0 g) was collected in the receiver. The resulting liquid (0.10 g) was mixed with benzotrifluoride (0.03 g) and 1,2-dimethoxyethane (1.00 g) for analysis, and analyzed by ¹⁹ F-NMR. As a result of the analysis, the resulting liquid was a fluorine-containing cyclic compound (8) (amount produced: 244.0 g, product mass: 0.87 mol, production rate: 96.8%).
In this embodiment, β/α was 1.1, and γ/δ was 1.1.
As described above, in the Examples, the fluorinated cyclic compound (5) was successfully produced in high yield even under low temperature conditions.

According to the present invention, it is possible to produce a fluorine-containing carboxylate (4) which has high reactivity even under low-temperature conditions and can be converted into various useful fluorine compounds with a stable and high yield. Furthermore, by using the fluorine-containing carboxylate (4) thus produced, it is possible to produce a fluorine-containing cyclic compound (5) with a high yield even under low-temperature conditions. Therefore, the present invention can be suitably used in the production of raw materials for various fluorine-containing compounds, ion exchange resins, ion exchange membranes, salt electrolysis membranes, fuel cell membranes, membranes for redox flow batteries, membranes for water electrolysis, etc.

Claims (3)

The following general formula (4):
_{FSO2CFXCF2OCF ( CF2Y} ) _CO2M (4)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; and M is K, Rb, or Cs.)
The present invention relates to a method for producing a fluorine-containing carboxylate (4) represented by the following formula:
The following general formula (1):
FSO ₂ CFXCF ₂ OCF (CF ₂ Y) COF (1)
(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
A fluorine-containing carboxylic acid fluoride (1) represented by the formula:
The following general formula (2):
_M2CO3 ( ₂ )
(In the formula, M is K, Rb, or Cs.)
and an alkali metal carbonate (2) represented by
The following general formula (3):
R ¹ (OR ² ) _p OR ³ (3)
(In the formula, R ¹ , R ² , and R ³ may be the same or different, and each represents an aliphatic or aromatic hydrocarbon group which may be substituted or unsubstituted and has 1 to 10 carbon atoms; and p is an integer from 2 to 10.)
The reaction is carried out in the presence of an ether-based compound (3) represented by the formula:
a ratio (β/α) of the amount of substance (β) of the alkali metal carbonate (2) to the amount of substance (α) of the fluorine-containing carboxylic acid fluoride (1) is 2 or less,
A method for producing a fluorine-containing carboxylate (4), characterized in that a ratio (δ/γ) of the mass (δ) of the ether compound (3) to the mass (γ) of the fluorine-containing carboxylic acid fluoride (1) exceeds 0.55. The method for producing a fluorine-containing carboxylate (4) according to claim 1, wherein the ether compound (3) is at least one selected from the group consisting of diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, and dipropylene glycol dimethyl ether. Obtaining a fluorine-containing carboxylate (4) by the method for producing a fluorine-containing carboxylate (4) according to claim 1 or 2;
heat-treating the obtained fluorine-containing carboxylate (4) ;
Characterized in that it comprises
The following general formula (5):

(In the formula, X is a fluorine atom, a chlorine atom, or a trifluoromethyl group; and Y is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.)
A method for producing a fluorine-containing cyclic compound (5) represented by the following formula: