JPH0329074B2 - - Google Patents

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), X ₁ , X ₂ , X ₃ , and X ₄ are
(a) Fluorine atom, (b) perfluoroalkyl group having 20 or less carbon atoms, and (c) -CF ₂ Y (Y contains at least one of a halogen atom and an ether bond, or the number of carbon atoms not containing it) is a hydrocarbon group of 20 or less.However, Y is a substituent selected from perfluoroalkyl groups. however,
At least one of the substituents of X ₁ , X ₂ , X ₃ , and X ₄ has a -CF ₂ - group directly bonded to the carbon-carbon double bond shown in general formula (1). , general formula (1)
The number of carbon atoms contained in the fluoroolefin represented by is between 4 and 25. Also, X ₁ , X ₂ , X ₃ , and
X ₄ may be linked to each other to form a 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 from hydrocarbon olefins such as propylene and chlorinated hydrocarbon olefins such as allyl chloride. Therefore, it is difficult to epoxidize fluoroolefin 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 fluoroolefin using the chlorohydrin method, chlorohydrin is unstable and decomposes into carbonyl compounds, so 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 based on fluoroolefins, which are industrially advantageous. This cannot be said to be a method for producing olefin epoxide.

Conventionally, there has been a method of oxidizing fluoroolefin to fluoroolefin epoxide in a medium of alkaline hydrogen peroxide, as described in U.S. Pat. A method of oxidizing fluoroolefin to fluoroolefin epoxide with oxygen in the presence of a solvent is known as a typical method for producing fluoroolefin epoxide. However, in any of these 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 a wide range of products is produced, making it difficult to obtain the fluoroolefin epoxide in high yield. It is not possible. Furthermore, in these methods, when the fluoroolefin conversion rate is increased, the fluoroolefin epoxide selectivity decreases, so in order to use the fluoroolefin effectively, it is necessary to stop the reaction at a low fluoroolefin conversion rate and remove unreacted fluoroolefin. It is necessary to separate and recover the fluoroolefin epoxide and reuse it. However, the boiling points of fluoroolefin and fluoroolefin epoxide are generally very close to each other, and it is difficult to separate the two by distillation.
Special separation operations are required for its separation. Examples include, for example, a method of reacting fluoroolefin with bromine to form a high-boiling dibrome compound and separating it from fluoroolefin epoxide;
Or US Pat. No. 3,326,780, US Pat.
Although the extractive distillation separation method described in the specification of No. 4134796 and the like have been proposed, all of them are complicated separation methods and significantly increase the production cost of fluoroolefin epoxide.

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 hypochlorite solution [IZV.AKAD.NAUK.
SSSR, SER.KHIM., 79, (11) 2509], but when the present inventors investigated this method, the selectivity of fluoroolefin epoxide was low and it was not possible to obtain a high yield. The reason for this is that the reaction rate is a homogeneous mixture of a polar solvent and an alkaline hypochlorite aqueous solution, so the produced fluoroolefin epoxide easily reacts with water and decomposes under alkaline conditions. It seems to be for a reason. 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 epoxide more easily than fluoroolefin and with a higher yield. The present inventors have discovered that fluoroolefin epoxide can be obtained in higher yield than fluoroolefin 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 the aqueous phase as an oxidizing agent, and the general formula (1)
In epoxidizing the fluoroolefin represented by be. (Hereinafter, the fluoroolefin represented by general formula (1) will be simply referred to as fluoroolefin, and
The fluoroolefin epoxide derived from the fluoroolefin represented by the general formula (1) is simply referred to as fluoroolefin epoxide. ) In the two-phase system reaction of the present invention, substantially all of the fluoroolefin and produced fluoroolefin epoxide 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 process of separating fluoroolefin and fluoroolefin epoxide and the process of recycling fluoroolefin.

After the reaction, the organic phase and the aqueous phase are separated, and the fluoroolefin epoxide is easily isolated 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 it is, making it very easy to recover the solvent and catalyst. .

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 and operation costs of the reactor are reduced, and a very economical process for producing fluoroolefin epoxide 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), X ₁ , X ₂ , X ₃ , and X ₄
is (a) a fluorine atom, (b) a perfluoroalkyl group having 20 or less carbon atoms, and (c) -CF ₂ Y (Y contains or does not contain at least one of a halogen atom and an ether bond) A hydrocarbon group having 20 or less carbon atoms.However, Y is a substituent selected from perfluoroalkyl groups. however,
At least one of the substituents of X ₁ , X ₂ , X ₃ , and X ₄ has a -CF ₂ - group directly bonded to the carbon-carbon double bond shown in general formula (1). , general formula (1)
The number of carbon atoms contained in the fluoroolefin represented by is between 4 and 25. Moreover, X ₁ , X ₂ , X ₃ and X ₄ may be linked to each other to form a cyclic compound. ] The fluoroolefin represented by these is used.

The substituted or unsubstituted hydrocarbon group Y contained in general formula (1) is one that can stably exist under alkaline conditions and in the presence of hypochlorite in the method of the present invention, or under the reaction conditions of the present invention. Various substituted or unsubstituted hydrocarbon groups can be used without any further restrictions, as long as they do not interfere with the reaction of the present invention even if modified below, but those of practical value include , , a carbonate group having 20 or less carbon atoms, which may or may not contain at least one of a halogen atom and an ether bond. However, Y does not include a perfluoroalkyl group.

Furthermore, there is no particular restriction on the length of the perfluoroalkyl group contained in the fluoroolefin of general formula (1), but those having a carbon number of 20 or less 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, perfluorooctadecene-1
1, perfluoro-4-methylpentene-2, perfluoro-4-methyl-pentene-3, perfluoro-4,6-dimethylheptene-4, perfluoro-2-methyl-3-isopropylpentene-3, perfluoroolefins such as perfluorocyclopentene and perfluorocyclohexene;
4,5-dichloroperfluoro-1-pentene,
5,6-dichloroperfluoro-1-hexene,
6,7-dichloroperfluoro-1-heptene,
9,10-dichloroperfluoro-1-decene,
Chlorofluoroolefins such as 4,6,7-trichloroperfluoro-1-heptene, bromofluoroolefins such as 4-bromoperfluorobutene-1, 5,6-dibromoperfluoro-1-hexene, 4-iodoperfluoro iodofluoroolefins such as butene-1, perfluoro-1,
Perfluorodienes such as 5-hexadiene and perfluoro-1,7-octadiene, ω-hydroperfluoroolefins such as ω-hydroperfluorohexene-1 and ω-hydroperfluorooctene-1, 1,1,2, 3,3-pentafluoro-
Polyfluoroolefins such as 1-butene, polyfluorodienes having both perfluoroallyl groups and vinyl groups, perfluoro-n-propoxy groups, perfluoro-i-propoxy groups, or oligomers of hexafluoropropylene oxide Fluoroolefin containing a perfluoroalkoxy group such as a perfluoroalkoxy group,
4-Perfluorovinyloxyperfluoro-1
- Perfluorovinyloxy group-containing fluoroolefins such as butene and the like can be mentioned.

Examples of hypochlorite used in the present invention include lithium hypochlorite, sodium hypochlorite, potassium hypochlorite, rubidium hypochlorite, cesium hypochlorite, etc. Examples include alkali metal salts and 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 as effective chlorine concentration
The range is preferably from 0.5% to 25%, particularly preferably from 1% to 20%. If the available chlorine concentration is too low, it is necessary to handle a large amount of aqueous phase, which is disadvantageous from a pharmaceutical standpoint. Furthermore, if the effective chloric acid concentration is too high, hypochlorite becomes unstable and difficult to handle.

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

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. Examples include sulfonium salts as shown in 2).

R ₁ R ₂ R ₃ S X (2) In the general formula (2), R ₁ , R ₂ and R ₃ 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. As the type of hydrocarbon group, for example, an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, an aralkyl group, an alkenylaryl group, etc. are used, and an alkyl group, an aryl group, an aralkyl group, etc. are particularly preferable. used. In addition, the length of the hydrocarbon group is usually from 6 to 6 per sulfonium ion as the total number of carbons contained in R ₁ , R ₂ and R ₃ .
It is selected from a range of 100 pieces, preferably from a range of 8 to 90 pieces, and particularly preferably from a range of 10 to 80 pieces. The above hydrocarbon group can also be used after being substituted with an inert functional group. The inert functional group is limited depending on the reaction conditions, but usually halogen, acyl group, carboxyl group, ester group, nitrile group, alkoxy group, etc. are used. In the R ₁ R ₂ R ₃ S ion, a heterocycle may be formed within the ion, or R ₁ , R ₂ or R ₃ may be part of a polymer compound.

Various anions can be used as the anion X in general formula (2), but halogen ions, various mineral acid ions other than halogen ions, organic acid ions, etc. are usually used.

Examples of the anion Examples include borate ion, difluorotrimethylsilicate ion, and the like.

Examples of the sulfonium salt represented by general formula (2) include dibutylmethylsulfonium iodide, tri-n-butylsulfonium tetrafluoroborate, dihexylmethylsulfonium 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-octadecylamino)sulfonium difluorotrimethylsilicate, tris(dimethylamino)sulfonium chloride, and the like.

The amount of sulfonium salt used in the method of the present invention is appropriately selected depending on the type of solvent, the required reaction rate, etc., but is usually from 0.0001 mol to 1 gram equivalent of hypochlorite ion used. It is selected from a range of 1 mol, particularly preferably from a 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 will be too fast and it will be difficult to control the reaction, and the cost burden of the sulfonium salt will increase, resulting in economical problems. This is disadvantageous.

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

Furthermore, when carrying out the method of the present invention, it is sufficient to have an organic phase containing substantially most of the fluoroolefin and an aqueous phase containing hypochlorite; It doesn't 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. Examples include, for example, n-hexane, n-octane,
Aliphatic hydrocarbons such as n-decane; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and decalin; aromatic hydrocarbons such as benzene, toluene, and xylene; ethers such as diisopropyl ether and di-n-butyl ether Chlorinated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, chlorobenzene; 1,2-dichloro-1,1,2,2-tetrafluoroethane, fluorotrichloromethane,
1,1,2-trichloro-1,2,2-trifluoroethane, 1,1,2,2-tetrachloro-
Chlorofluorocarbons such as 1,2-difluoroethane; perfluorocarbons such as perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorohexane, perfluorooctane, perfluorodecane, hexafluorobenzene; or mixed solvents thereof, etc. Examples include, but are not limited to. When selecting an organic solvent, consider the solubility for fluoroolefin and fluoroolefin epoxide, the solubility for the sulfonium salt 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 chosen. Among the various solvents mentioned above, fluorine-containing compounds such as chlorofluorocarbons and perfluorocarbons are suitable for the method of the present invention because they have high solubility in fluoroolefin and fluoroolefin epoxide and low compatibility with water. In addition, chlorinated hydrocarbons generally have high solubility in sulfonium salts and are therefore suitable for the method of the present invention.

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 preferably 0.05 to 20 times the aqueous phase, and particularly preferably.
It ranges from 0.2 times to 5 times.

The reaction temperature when carrying out the present invention is determined depending on the amount of sulfonium salt, reaction solution composition, required reaction rate, etc., but is usually in the range of -25°C to 80°C, preferably -20°C. A range of 0.degree. C. to 60.degree. C. is used, particularly preferably a range of -18.degree. C. to 40.degree. 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 when 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 the 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 batch 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 In a 50 ml pressure bottle containing a stirring bar coated with fluorine resin, 18 ml of chloroform and 20 mL of an aqueous sodium hypochlorite solution with an effective chlorine concentration of 12% were added.
ml, 3.5 g (10 mmol) perfluoro-1-heptene and 0.12 g (0.42 mmol) di-n-butylmethylsulfonium iodide. Next, this reaction solution is cooled to 0° C., and then a magnetic stirrer is used to rotate a stirrer in the reaction container to mix the reaction solution and start the reaction. The reaction temperature is maintained at 0°C during the reaction. After 30 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.
When 1-heptene and 1,2-epoxy perfluoroheptane were quantified by gas chromatography, the conversion rate of perfluoro-1-heptene was 94.
%, the selectivity of 1,2-epoxy perfluoroheptane was 71%.

Comparative Example 1 A reaction similar to Example 1 was carried out without using di-n-butylmethylsulfonium iodide. As a result, only a trace amount of 1,2-epoxy perfluoroheptane was produced.

Example 2 The same operation as in Example 1 is carried out, but instead of the sodium hypochlorite aqueous solution, an effective chlorine content of 65% is used.
Using 20 ml of an aqueous solution containing 4.6 g of high-grade salashi powder (main ingredient is calcium hypochlorite), the reaction temperature was 30
When the reaction was carried out at a temperature of 20 minutes, the conversion of perfluoro-1-heptene was 86% and the selectivity of 1,2-epoxy perfluoroheptane was 67%.

Example 3 The same reaction as in Example 1 was carried out using 0.20g of di-n-butylmethylsulfonium iodide as a catalyst instead of 0.12g, and at a reaction temperature of -10°C instead of 0°C. However, perfluoro-
The conversion rate of 1-heptene was 89%, and the selectivity of 1,2-epoxy perfluoroheptane was 75%.

Example 4 The same reaction as in Example 1 was carried out, but instead of 0.12 g of di-n-butylmethylsulfonium iodide,
When carried out using 0.12 g of tri-n-butylsulfonium tetrafluoroborate, the conversion of perfluoro-1-heptene was 75% and the selectivity of 1,2-epoxy perfluoroheptane was 68%.

Example 5 The same reaction as in Example 1 was carried out, but instead of 0.12 g of di-n-butylmethylsulfonium iodide,
Methyldioctadecylsulfonium iodide
When using 0.30g, the reaction time was 20 minutes,
Conversion rate of perfluoro-1-heptene 91%, 1,
Selectivity of 2-epoxy perfluoroheptane 73%
It was hot.

Example 6 The same reaction as in Example 1 was carried out, but instead of 0.12 g of di-n-butylmethylsulfonium iodide,
Tris (N-methyl-N-octadecylamino)
Sulfonium difluorotrimethyl silicate
When the reaction was carried out using 0.30 g, the conversion rate of perfluoro-1-heptene was 60% in 1 hour,
Selectivity of 1,2-epoxy perfluoroheptane
It was 62%.

Example 7 The same reaction as in Example 1 was carried out using 2.0 g of perfluoro-2-butene instead of perfluoro-1-heptene.
(10 mmol) was used. As a result, the conversion rate of perfluoro-2-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 perfluorocyclopentene instead of perfluoro-1-heptene.
2.12 g (10 mmol) was used. As a result, the conversion rate of perfluorocyclopentene was 89%,
The selectivity for perfluoro-1,2-epoxycyclopentane was 77%.

Example 9 A reaction similar to Example 1 was carried out using 3.33 g (10 mmol) of 5,6-dichloroperfluoro-1-hexene instead of perfluoro-1-heptene. Conversion rate of 5,6-dichloroperfluoro-1-hexene 80%, 1,2-epoxy-5,6-
The selectivity for dichloroperfluorohexene was 61%.

Example 10 The same reaction as in Example 1 was carried out using ω-hydroperfluoro-1-instead of perfluoro-1-heptene.
It was carried out using 3.44 g (10 mmol) of octene.
As a result, the conversion rate of ω-hydroperfluoro-1-octene was 70%, and the selectivity of 1,2-epoxy-ω-hydroperfluorooctane was 65%.

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

Example 12 The same reaction as in 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 65%.
It was 58%.

Example 13 A reaction similar to Example 1 was carried out using 3.00 g (10 mmol) of perfluoro-4-methylpentene-2 instead of perfluoro-1-heptene. As a result, the conversion rate of perfluoro-4-methylpentene-2 was 52%, and the selectivity of perfluoro-2,3-epoxy-4-methylpentane was 61%.

Claims (1)

[Claims] 1. Using a solvent or suspended hypochlorite in an aqueous phase as an oxidizing agent, in the presence or absence of an inorganic base, the general formula (1) [In general formula (1), X ₁ , X ₂ , X ₃ , and X ₄
is (a) a fluorine atom, (b) a perfluoroalkyl group having 20 or less carbon atoms, and (c) -CF ₂ Y (Y is a carbon atom containing or not containing at least one of a halogen atom and an ether bond). is a hydrocarbon group having a number of 20 or less.However, Y is a substituent selected from perfluoroalkyl groups. however,
At least one of the substituents of X ₁ , X ₂ , X ₃ , and X ₄ has a -CF ₂ - group directly bonded to the carbon-carbon double bond shown in general formula (1). , general formula (1)
The number of carbon atoms contained in the fluoroolefin represented by is between 4 and 25. X ₁ , X ₂ , X ₃ , and X ₄
They may be linked to each other to form a cyclic compound. ] A method for epoxidizing a fluoroolefin, 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. The 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. R ₁ R ₂ R ₃ S X (2) [However, in formula (2), R ₁ , R ₂ and R ₃ are the same or
Alternatively, it represents a hydrocarbon group or a secondary amino group. The R ₁ R ₂ R ₃ S ion may form a heterocycle within the ion. The size of R ₁ , R ₂ and R ₃ is from 6 to 100 per sulfonium ion as the total number of carbons contained in R ₁ , R ₂ and R ₃ .
The range of X 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.