JPS59110687A - Epoxidation of fluoroolefin - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as an intermediate for synthesizing various kinds of fluorine-contained compounds in high yield, by reacting a fluoroolefin with a hypochlorite as an oxidizing agent in the presence of a sulfonium salt in a two-phase system of a water phase and an organic phase. CONSTITUTION:A fluoroolefin shown by the formula I (X1, X2, X3, and X4 are F, <=20C perfluoroalkyl, etc.) is reacted with a hypochlorite in the presence of a sulfonium salt shown by the formula II(R1, R2, and R3 are hydrocarbon or secondary amino; X<-> is anion) in a two-phase system of an organic phase containing the fluoroolefin and a water phase containing the hypochlorite usually at -25-80 deg.C, to give the desired compound. EFFECT:Decomposition caused by contact with an alkali aqueous solution is prevented. Chlorinated hydrocarbons have high solubility in the sulfonium salt and suitable for this process. The initial cost and operating cost of a reactor is low and economic. A catalyst and solvent can be circulated and reused.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for epoxidizing fluoroolefins. More specifically, the present invention relates to a method of epoxidizing a fluoroolefin represented by general formula (1) using hypochlorite as an oxidizing agent.

[In general formula (1), X5, x, x3 and 4 are
fa) a fluorine atom, (bl a perfluoroalkyl group having 20 or less carbon atoms, and (C1-CFLy), (Y contains at least one of a halogen atom and an ether bond or does not contain a carbon number of 20 or less); It is a hydrocarbon group.However, Y does not include a perfluoroalkyl group.

) is a substituent selected from However, among the substituents of 4, X3 and X4, at least one ζ also has the general formula (11
The number of carbon atoms contained in the fluoroolefin represented by the general formula (1) is between 4 and 25, and has a -CF2- group directly bonded to the carbon-carbon double bond shown in be. Moreover, X5, x2, X3 and X4 may be connected to each other to form a complete cyclic compound. ] The fluoroolefin epoxide is highly reactive and is important as a synthetic intermediate for various fluorine-containing compounds, and is itself an important substance that can be used as a raw material for polymeric compounds.

In general, fluoroolefin epoxides can be produced by the epoxidation reaction of fluoroolefins, but fluoroolefins have very different chemical properties than hydrocarbon olefins such as propylene or chlorinated hydrocarbon olefins such as allyl chloride. Therefore, it is difficult to epoxidize fluoroolefins in the same manner as propylene or allyl chloride.

For example, both propylene and allyl chloride are epoxidized by the chlorohydrin method, in which the ring is closed with an alkali via chlorohydrin. On the other hand, when attempting to epoxidize fluoroolefins using the chlorohydrin method,
Since chlorohydrin is unstable and decomposes into carbonyl compounds, it cannot be converted into fluoroolefin epoxide.

Therefore, various methods have been proposed for epoxidizing fluoroolefins that are different from those for hydrocarbon olefins and chlorinated hydrocarbon olefins, but all of them are industrially advantageous for epoxidizing fluoroolefins. It cannot be said to be a method of manufacturing epoxide.

Conventionally, there has been a method of oxidizing a fluoroolefin to a fluoroolefin epoxide in a medium of alkaline hydrogen peroxide, as described in U.S. Pat. A method of oxidizing a fluoroolefin to a fluoroolefin epoxide with oxygen in the presence of a solvent is known as a typical method for producing a fluoroolefin epoxide. However, even with these σ1 deviation methods, it is difficult to control the reaction, it is difficult to suppress the decomposition of the produced fluoroolefin epoxide, or a large amount of by-products are produced, making it difficult to produce fluoroolefin epoxide in high yield. You can't get it. Furthermore, in these methods, when the fluoroolefin conversion rate is increased, the fluoroolefin epoxide selectivity decreases, so in order to effectively use fluoroolefins, it is necessary to stop the reaction at a low fluoroolefin conversion rate and remove unreacted fluoroolefins. It is necessary to separate and recover the fluoroolefin epoxide and reuse it. However, in general, the boiling points of fluoroolefins and fluoroolefin epoxides are very close to each other, and it is difficult to separate them by distillation, so a special separation operation is required for their separation. Examples include, for example, a method in which a fluoroolefin and bromine are reacted to form a high-boiling dibromine compound and separated from a fluoroolefin epoxide, or US Pat. No. 3,326,780 and US Pat. No. 41
Although extractive distillation separation methods such as those described in Patent No. 34796 have been proposed, all of them are complicated separation methods and significantly increase the production cost of fluoroolefin epoxides.

On the other hand, as an oxidation method using hypochlorite, it is known that fluoroolefin epoxide is produced from fluoroolefin in a system in which a polar solvent such as acetonitrile or diglyme is added to an aqueous solution of hypochlorite.
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), but when the present inventors investigated this method, the selectivity of the fluoroolefin epoxide was low and it was not possible to obtain a high yield. This is because the reaction system is a homogeneous mixture of a polar solvent and an alkaline hypochlorite aqueous solution, so the generated fluoroolefin epoxide easily reacts with water and decomposes under alkaline conditions. I think that the. Furthermore, this method requires a troublesome step of recovering the polar solvent from the reaction system after the reaction. From the above points, this reaction method also cannot be a practical technology for producing fluoroolefin epoxide.

The inventors of the present invention have conducted intensive studies to overcome the drawbacks of conventional methods and to find a method for producing fluoroolefin epoxides more easily and with higher yields than fluoroolefins. The present inventors have discovered that fluoroolefin epoxides can be obtained in higher yields than fluoroolefins when the reaction is carried out in a two-phase system of an aqueous phase and an organic phase in the presence of a sulfonium salt, and the present invention has been completed.

That is, the present invention uses hypochlorite dissolved or suspended in an aqueous phase as an oxidizing agent to epoxidize a fluoroolefin represented by general formula (1) in the presence of a sulfonium salt. The present invention provides a novel method for epoxidizing fluoroolefins, which is characterized by carrying out the reaction in a two-phase system of an aqueous phase and an organic phase. (Hereafter, general formula +11
The fluoroolefin represented by is simply referred to as fluoroolefin, and the fluoroolefin epoxide derived from the fluoroolefin represented by general formula (1) is simply referred to as fluoroolefin epoxide. ) In the two-phase reaction of the present invention, substantially all of the fluoroolefins and produced fluoroolefin epoxides are contained in the organic phase. According to the method of the present invention, fluoroolefin epoxide can be obtained with high selectivity even if the conversion rate of fluoroolefin is increased. This is thought to be because the presence of fluoroolefin epoxide makes it difficult for the fluoroolefin epoxide to decompose upon contact with an alkaline aqueous solution. Therefore, according to the method of the present invention, by increasing the fluoroolefin conversion rate, it is also possible to omit the complicated step of separating fluoroolefin and fluoroolefin epoxide and the step of recycling fluoroolefin.

After the reaction, the organic phase and the aqueous phase are separated, and the fluoroolefin epoxide is easily separated from the organic phase by a separation operation such as distillation. In addition, the remaining organic phase from which the fluoroolefin epoxide has been removed contains a catalyst, and this remaining organic phase can be recycled and reused in the reaction as is, making recovery of the solvent and catalyst very easy. be.

As described above, in the method of the present invention, fluoroolefin epoxide can be obtained in high yield, and the manufacturing process is extremely simple. Therefore, when carrying out the method of the present invention, the construction cost and operating cost of the reactor are reduced, and a very economical fluoroolefin epoxide production process is made possible.

The present invention will be explained in more detail below.

In the method of the present invention, general formula (1) (in general formula (1), X2, X2, X3 and 4 are
(al fluorine atom, (b) perfluoroalkyl group having 20 or less carbon atoms, and (C) to CF, Y (Y contains at least one of a halogen atom and an ether bond, or has a carbon number not containing it) It is a hydrocarbon group of 20 or less.

However, Y does not include a perfluoroalkyl group. ) is a substituent selected from However, among the substituents of Xl, X2, X3 and X4, at least one is directly bonded to the carbon-carbon double bond shown in general formula (1) -CF
2-group, and the number of carbon atoms contained in the fluoroolefin represented by the general formula (11) is between 4 and 25.
X2, X2, X3 and X4 may be linked to each other to form a cyclic compound. ] is used.

Substituted or unsubstituted hydrocarbon group Y contained in general formula fil
is a substance that can stably exist under alkaline conditions and in the presence of hypochlorite in the method of the present invention, or does not interfere with the reaction of the present invention even if denatured under the reaction conditions of the present invention. , without any further restrictions, various substituted or unsubstituted hydrocarbon groups may be used, but those of practical value include those containing at least one of a halogen atom and an ether bond, or not containing at least one of them. Examples include hydrocarbon groups having 20 or less carbon atoms. However, Y does not include a perfluoroalkyl group.

Further, there is no particular restriction on the length of the perfluoroalkyl group contained in the fluoroolefin of general formula (1), but those having 20 or less carbon atoms are exemplified as substantially useful ones.

Examples of fluoroolefins used in the method of the present invention include, for example, perfluoro-2-butene, perfluoro-1-butene, perfluoro-2-pentene, perfluoro-1-hexene, perfluoro-2-hexene. , perfluoroheptene-1, perfluorononene-1
, perfluorododecene-1, perfluoroolefin-1, perfluoro-4-methylpentene-2, perfluoro-4-methyl-pentene-3, perfluoro-4
, 6-dimethylhebutene-4, perfluoro-2-methyl-3-isopropylpentene-3, perfluorocyclopentene, perfluorocyclopentene, etc., 4,5-dichloroperfluoro-1
-pentene, 5゜6-cycloperfluoro-1-hexene, 6.7-cycloperfluoro-1-heptene,
9.10-dichloroperfluoro-1-decene, 4,6
．． Chlorofluoroolefins such as 7-dolichlorofluoro-1-heptene, bromofluoroolefins such as 4-bromoperfluorobutene-1,5,6-dibromoperfluoro-1-hexene, 4-iodoperfluorobutene-1 iodofluoroolefins such as perfluoroolefins, perfluorodienes such as 5-hexadiene, perfluoro-1,7-octadiene, ω-hydroperfluorohexene-1, ω-hydroperfluorooctene-
ω-hydroperfluoroolefins such as 1, 1, 2
, 3. Polyfluoroolefins such as 3-pentafluoro-1-butene, polyfluorodienes having both perfluoroallyl groups and vinyl groups, perfluoro-n-propoxy groups, perfluoro-1-propoxy groups or hexa Examples include fluoroolefins containing perfluoroalkoxy groups such as perfluoroalkoxy groups derived from oligomers of fluoropropylene oxide, and fluoroolefins containing perfluorovinyloxy groups such as 4-perfluorovinyloxyperfluoro-1-butene. .

Examples of the hypochlorite used in the present invention include lithium hypochlorite, sulfur/lium hypochlorite, potassium hypochlorite, rubidium hypochlorite, cesium hypochlorite, etc. or alkaline earth metal salts such as magnesium hypochlorite, calcium hypochlorite, strontium hypochlorite, and barium hypochlorite.

Among them, sodium hypochlorite and calcium hypochlorite in particular are industrially mass-produced for use as bleaching agents, disinfectants, etc., and can be obtained at low cost. Suitable as an acid salt. As the hypochlorite, a commercially available product may be used as it is, or one prepared from an inorganic base and chlorine gas, or one prepared by non-diaphragm electrolysis of an inorganic chloride may be used.

In the present invention, the hypochlorite is mainly used dissolved in the aqueous phase, but there is no particular restriction on its concentration. Usually, the effective chlorine concentration is preferably in the range of 0.5% to 25%, particularly preferably in the range of 1% to 20%. If the available chlorine concentration is too low, it is necessary to handle a large amount of aqueous phase, which is economically disadvantageous. Furthermore, if the effective chloric acid concentration is too high, hypochlorite becomes unstable and difficult to handle.

The ratio of the hypochlorite to the fluoroolefin can be selected arbitrarily, but in order to obtain substantial reaction results, it is usually 0.5 gram equivalent of hypochlorite ion per mole of the fluoroolefin. to 30 gram equivalents, preferably from 0.8 gram equivalents to 10 gram equivalents, and particularly preferably from 1 gram equivalents to 5 gram equivalents.

The method of the invention can be carried out either in the presence or absence of an inorganic base.

The sulfonium salt used in the method of the present invention is preferably one that exists stably under the reaction conditions and has an affinity for the organic phase or both the organic phase and the aqueous phase.
For example, sulfonium salts represented by general formula (2) can be mentioned.

In general formula (2), R, , R2 and R3 are the same or different and represent a hydrocarbon group or a secondary amino group. The type and length of the hydrocarbon group contained in the hydrocarbon group or secondary amino group are appropriately selected depending on the solvent used, the required reaction rate, etc. Examples of the types of hydrogen flashed groups include alkyl groups, alkenyl groups, cycloalkyl groups, cycloalkenyl groups, aryol groups, aralkyl groups, alkenylaryl groups, and particularly preferred are alkyl groups and aryolyl groups. Aralkyl groups, aralkyl groups, etc. are used. In addition, the lengths of the hydrocarbon groups are R3, R2
and the total number of carbon atoms contained in R3 is usually selected from the range of 61 to 1001 carbons per 11 sulfonium ions, preferably from the range of 8 to 90 carbons,
Particularly preferably, the number is selected from the range of 10 to 80.

The above hydrocarbon group can also be used after being substituted with an inert functional group. The inert functional groups are limited depending on the reaction conditions, but are usually halogens, acyl groups, carboxyl groups,
Ester groups, nitrile groups, alkoxy groups, etc. are used. In the R,'R,R3S'E' ion, a heterocycle may be formed within the ion, or R1, R2, or R3 may be part of a polymer compound.

As the anion ρ in the general formula (2), various anions can be used, but normally, halogen ions, various mineral acid ions other than halogen ions, organic acid ions, etc. are used.

Examples of the anion ρ include chloride ion, bromide ion, iodide ion, fluoride ion, hydrogen sulfate ion, sulfate ion, nitrate ion, phosphate ion, perchlorate ion,
Examples include p-toluenesulfonic acid ion, tetrafluorobore 1-ion, cyfluorotrimethylsilicate 1-ion, and the like.

' Examples of the sulfonium salt represented by the general formula [2] include dibutylmethylsulfonium iodide,
tri-butylsulfonium tetrafluoroborate, dibutylmethylsulfonium iodide, dicyclohexylmethylsulfonium iodide, dodecylethylmethylsulfonium chloride, methyldioctadecylsulfonium iodide, dodecylbenzylmethylsulfonium methylsulfate (1,,6-hexamethylenebis) (dimethylsulfonium bromide), tris(dimethylamino)sulfonium difluorotrimethylsilicate, tris(diethylamino)sulfonium difluorotrimethylsilicate, tris(N-methyl-N-occudecylamino)sulfonium difluorotrimethylsilicate, tris(dimethylamino)sulfonium Examples include chloride.

The amount of sulfonium salt used in the method of the present invention is appropriately selected depending on the type of solvent, required reaction rate, etc.

is usually selected from a range of 0.0001 mol to 1 mol per gram equivalent of hypochlorite ion used,
Particularly preferably, the amount is selected from the range of 0.001 mol to 0.3 mol. If the amount of sulfonium salt is too small, a substantial reaction rate cannot be obtained, and if it is too large, the reaction rate is too fast and it becomes difficult to control the reaction, and the cost burden of the sulfonium salt increases. It is economically disadvantageous.

The reaction of the present invention is carried out in a two-phase system consisting of an aqueous phase and an organic phase. The organic phase in this case only needs to contain a fluoroolefin and form a phase different from the aqueous phase, and there are no particular restrictions beyond that. Alternatively, it may be a phase consisting of a sulfonium salt and a fluoroolefin that are poorly soluble in water,
Furthermore, the phase may be composed of an inert solvent and a fluoroolefin that are substantially immiscible or hardly miscible with the aqueous phase.

Furthermore, when carrying out the process of the present invention, it is sufficient to have an organic phase containing substantially the majority of the fluoroolefins and an aqueous phase containing hypochlorite; It does not matter if there are other phases.

For example, the present invention can be applied even when the organic phase is composed of two types of media with low compatibility to form two phases, or when a sulfonium salt is supported on an insoluble carrier and forms a third phase. How can you do it?

As the organic solvent for the organic phase used in the method of the present invention, an inert solvent that is substantially immiscible or poorly miscible with the aqueous phase is used. For example, n-
Aliphatic hydrocarbons such as hexane, n-octane, and n-decane; Alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and decalin; Aromatic hydrocarbons such as benzene, toluene, and xylene; Diisopropyl ether, di- Ethers such as n-butyl ether; methylene chloride,
Chloroform, carbon tetrachloride, 112-dichloroethane,
Chlorinated hydrocarbons such as chlorobenzene; 1,2-dichloro-LL2.2-tetrafluoroethane, fluorotrichloromethane, LL2-)dichloro-L2,2-)lifluoroethane, LL2.2-tetrachloro-1 ,2-
Chlorofluorocarbons such as difluoroethane; perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorohexane, perfluorooctane,
Examples include, but are not limited to, perfluorocarbons such as perfluorodecane and hexafluorobenzene, or mixed solvents thereof. When selecting an organic solvent, consider factors such as solubility in fluoroolefins and fluoroolefin epoxides, solubility in sulfonium salts used in the reaction, phase separation from the aqueous phase, and reaction conditions such as reaction pressure and reaction temperature. A suitable organic solvent is selected. Among the various solvents mentioned above, fluorine-containing compounds such as chlorofluorocarbons and perfluorocarbons have high solubility in fluoroolefins and fluoroolefin epoxides, and low compatibility with water, so they are suitable for the method of the present invention. Chlorinated hydrocarbons are also suitable for the process of the invention because they generally have a high solubility for sulfonium salts.

The volume ratio of the organic phase to the aqueous phase can be arbitrarily selected depending on the reaction method, reaction conditions, etc., but the organic phase is usually desirably 0.05 to 20 times the aqueous phase, particularly preferably 0.2 to 20 times the aqueous phase. 5
This is twice the range.

The reaction temperature when carrying out the present invention is determined depending on the amount of sulfonium salt, the composition of the reaction solution, the required reaction rate, etc., but it is usually in the range of -25°C to 80°C, and is preferably A range of -20°C to 63'C is used, particularly a range of -18°C to 40°C is used.

If the reaction temperature is too low, a substantial reaction rate may not be obtained, or in some cases, the aqueous phase may freeze, making it impossible to carry out the reaction. On the other hand, if the reaction temperature is too high, the decomposition of the fluoroolefin epoxide becomes significant and the selectivity of the fluoroolefin epoxide decreases.

The reaction pressure in carrying out the present invention is not particularly limited as long as it is a pressure sufficient to keep the organic phase containing the fluoroolefin and fluoroolefin epoxide in a liquid phase. Therefore, the reaction pressure is selected depending on the type and composition of the organic phase, but is usually preferably in the range of 1 atm to 20 atm.

As a method for carrying out the two-phase reaction of the present invention, any of the hatch method, semi-flow method, and flow method can be used.

EXAMPLES The present invention will be explained in more detail below using Examples and Comparative Examples, but these explanations are not intended to limit the present invention in any way.

Example 1 Content volume 5 containing a stirrer coated with fluororesin
In a 0ml pressure bottle, add 18ml of chloroform and 20ml of sodium hypochlorite aqueous solution with an effective chlorine concentration of 12%.
% perfluoro-1-heptene (<10 mmol) and 0.12 g (0.42 mmol) of di-butylmethylsulfonium iodide. Next, after cooling this reaction solution to 0° C., a stirrer in the reaction container is rotated using a magnetic cooler to mix the reaction solution and start the reaction. The reaction temperature is maintained at 0°C during the reaction. 3
After 0 minutes, the rotation of the stirrer was stopped and the reaction solution was allowed to stand still to separate the aqueous phase and chloroform phase. As determined by graphography, the conversion rate of barfol 1-heptene was 94%,
Selectivity of 1,2-epoxy perfluorohebutane 71%
Met.

Comparative Example 1 A reaction similar to Example 1 was carried out without using di-n-butylmethylsulfonium iodide.

As a result, Example 2 of 1,2-epoxy perfluorohebutane The same operation as in Example 1 was carried out, but instead of the sodium hypochlorite aqueous solution, highly refined powder with an available chlorine content of 65% (main component Using 20ml of an aqueous solution containing 4.6g of calcium hypochlorite, the reaction temperature was 30°C and the reaction time was 20°C.
When the reaction was carried out for 1 minute, the conversion rate of perfluoro-1-heptene was 86% and the selectivity of 1,2-epoxy perfluorohebutane was 67%.

Example 3 The same reaction as in Example 1 was carried out using 0.12g of di-n-butylmethylsulfonium iodide as a catalyst instead of 0.12g.
20g, and the reaction temperature was -1 instead of 0°C.
When carried out at 0°C, the conversion rate of perfluoro-1-heptene to nitrate was 89% and the selectivity of 1,2-epoxy perfluorohebutane was 75%.

Example 4 A reaction similar to Example 1 was carried out using 1.0 g of di-n-butylmethylsulfonium iodide instead of 0.12 g. tree n
-Butylsulfonium tetrafluoroborate 0.12
The conversion rate of perfluoro-1-heptene was 75% and the selectivity of 1,2-epoxy perfluorobutane was 68%.

Example 5 The same reaction as in Example 1 was carried out using 0.30 g of methyldioctadecylsulfonium iodide instead of 0.12 g of di-n-butylmethylsulfonium iodide, and the reaction time was 20 minutes. , perfluoro-
The conversion rate of 1-heptene was 91%, and the selectivity of 1,2-epoxy perfluorohebutane was 73%.

Example 6 The same reaction as in Example 1 was carried out using tris(N
-Methyl-N-octadecylamino)sulfonium difluorotrimethylsilicate (0.30 g), the reaction time was 1 hour, the conversion rate of perfluoro-1-heptene was 60%, and the conversion rate of perfluoro-1-heptene was 60%. The selectivity was 62%.

Example 7 The same reaction as in Example 1 was carried out using perfluoro-2-butene 2.0 instead of perfluoro-2-heptene. <10 mmol). As a result, Pafluoro 2
-The conversion rate of butene was 85%, and the selectivity of 2,3-epoxy perfluorobutane was 70%.

Example 8 The same reaction as in Example 1 was carried out using 2.12 g (10
mmol). As a result, the conversion rate of perfluorocyclopentene was 89%, and perfluoro-1,2
- The selectivity for epoxycyclobencune was 77%.

Example 9 The same reaction as in Example 1 was carried out using 3.33 g (10 mmol) of 5,6-cycloperfluoro-1-hexene instead of perfluoro-1-heptene.

The conversion rate of 5,6-cycloperfluoro-1-hexene was 80%, and the selectivity of 1,2-epoxy-5,6-cycloperfluorohexane was 61%.

Example 10 The same reaction as in Example 1 was carried out using 3.4 ω-hydroperfluoro-1-octene instead of perfluoro-1-heptene.
4 g (10 mmol) was used. As a result, the conversion of ω-hydroperfluoro-1-octene ([70
%, the selectivity for 112-epoxy-ω-hydroperfluorooctane was 65%.

Example 11 The same reaction as in Example 1 was carried out using 2.62% perfluoro-1,5-hexadiene instead of perfluoro-1-heptene.
g (10 mmol), 1.
Production of 2-epoxyperfluoro-5-hexene was observed.

Example 12 A reaction similar to Example 1 was carried out using 5.22 g (10 mmol) of 7,8-dibromoperfluoro-1-octene in place of perfluoro-1-hexene. As a result, the conversion rate of 7,8-dibromoperfluoro-1-octene was 65%, and the selectivity of 1,2-epoxy-7,8-dibromoperfluorooctane was 58%.

Example 13 The same reaction as in Example 1 was carried out using perfluoro-4-methylpentene-2 instead of perfluoro-1-heptene.
00g (10 mmol). As a result, the conversion rate of perfluoro-4-methylpentene-2 was 5
2%, and the selectivity for perfluoro-2,3-epoxy-4-methylpentane was 61.

Patent applicant: Asahi Kasei Industries, Ltd. Agent Patent Attorney Toru Hoshino

Claims (2)

[Claims] (1) Using a solvent or suspended hypochlorite in the aqueous phase as an oxidizing agent, in the presence or absence of an inorganic base, the general formula (1) [In the general formula (1), Xl, X2 . A hydrocarbon group having 20 or less carbon atoms.However, Y is not a perfluoroalkyl group.However, among the substituents of x, X, Xl and X4, At least one -C is directly linked to the carbon-carbon double bond shown in general formula (1)
The number of carbon atoms contained in the fluoroolefin having an F2- group and represented by the general formula (1) is between 4 and 25. X
l, X2, Xl and 4 may be linked to each other to form a cyclic compound. ] A method for epoxidizing fluoroolefins, which is characterized in that the reaction is carried out in a two-phase system of an aqueous phase and an organic phase in the presence of a sulfonium salt. (2) A method for epoxidizing fluoroolefins according to claim 1, characterized in that a sulfonium salt represented by general formula (2) is used as the sulfonium salt. [However, in formula (2), R, R2 and R5 are the same as each other,
Alternatively, it represents a hydrocarbon group or a secondary amino group. In the R, R2R3φ ion, a heterocycle may be formed within the ion. The sizes of R1, R2 and R3 are R1, R
The total number of carbon atoms contained in 2 and R6 ranges from 6 to 100 per sulfonium ion, and ρ represents an organic or inorganic anion. (3) The method for epoxidizing fluoroolefins according to claim 1 or 2, characterized in that sodium hypochlorite or calcium hypochlorite is used as the hypochlorite. .