METHOD FOR PURIFYING PHOSPHORUS-CONTAINING OLEFIN COMPOUND SALT AND METHOD FOR PRODUCING OLEFIN COMPOUND USING PURIFIED PRODUCT OBTAINED THEREBY

Abstract

Provided is a method for purifying a phosphorus-containing olefin compound salt as a raw material or an intermediate that is useful to increase the purity of a target product in a method for producing an olefin compound and that can be applied to the production method, and a method for producing an olefin compound using a purified product obtained thereby.

Specifically, provided is a method for purifying a phosphorus-containing olefin compound salt, comprising reprecipitating and/or recrystallizing a solid comprising at least one phosphorus-containing olefin compound salt selected from the group consisting of: a phosphorus-containing olefin compound salt A represented by the following formula (1):

##STR00001##

wherein X.sub.1 and X.sub.2 are each independently F, Cl, Br, I, or H; W.sup.+s are the same or different and each is a monovalent cation comprising PR.sub.3 or P(OR).sub.3, provided that Rs are groups having a saturated or unsaturated structure containing C and H, are optionally bonded together to form a ring, and optionally contain an atom other than C and H; three Rs included in R.sub.3 and (OR).sub.3 are optionally the same or different; and M.sup.− is a monovalent anion comprising an atom or a compound; and a phosphorus-containing olefin compound salt B represented by the following formula (2):

##STR00002##

wherein X.sub.1, X.sub.2, W.sup.+, and M.sup.− are as defined above, and Y is F, Cl, Br, I, H, an alkyl group, an alkyl ether group, a fluoroalkyl group, or a fluoroalkyl ether group; in a solvent, thereby obtaining a purified product of the phosphorus-containing olefin compound salt.

Claims

1. A method for purifying a phosphorus-containing olefin compound salt, comprising reprecipitating and/or recrystallizing a solid comprising at least one phosphorus-containing olefin compound salt selected from the group consisting of: a phosphorus-containing olefin compound salt A represented by the following formula (1): ##STR00016## wherein X.sub.1 and X.sub.2 are each independently F, Cl, Br, I, or H; W.sup.+s are the same or different and each is a monovalent cation comprising PR.sub.3 or P(OR).sub.3, provided that Rs are groups having a saturated or unsaturated structure containing C and H, are optionally bonded together to form a ring, and optionally contain an atom other than C and H; three Rs included in R.sub.3 and (OR).sub.3 are optionally the same or different; and M.sup.− is a monovalent anion comprising an atom or a compound; and a phosphorus-containing olefin compound salt B represented by the following formula (2): ##STR00017## wherein X.sub.1, X.sub.2, W.sup.+, and M.sup.− are as defined above, and Y is F, Cl, Br, I, H, an alkyl group, an alkyl ether group, a fluoroalkyl group, or a fluoroalkyl ether group; in a solvent, thereby obtaining a purified product of the phosphorus-containing olefin compound salt wherein after the solid is dissolved in a solvent at 45 to 60° C., the temperature of a solution is reduced at −0.25° C./min or less to thereby perform reprecipitation and/or recrystallization.

2. The purification method according to claim 1, wherein the solvent is at least one member selected from the group consisting of ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, methanol, ethanol, propanol, isopropanol, and butanol.

3. (canceled)

4. The purification method according to claim 1, further comprising extracting the purified product by suction filtration and/or pressure filtration.

5. The purification method according to claim 1, wherein the solid comprises at least one compound selected from the group consisting of: (trans-2-perfluoropropoxy-1,2-difluoroethen-1-yl)(tributyl) phosphonium tetrafluoroboranuide, (cis-2-perfluoropropoxy-1,2-difluoroethen-1-yl)(tributyl) phosphonium tetrafluoroboranuide, perfluoropropoxy vinyl ether, (2,2,3,3,3-pentafluoro-1-tributylphosphin-1-one) tetrafluoroboranuide, boron trifluoride tributylphosphine oxide, tetrafluoroboric acid, (1,2-difluoroethen-1-yl)(tributyl) phosphonium tetrafluoroboranuide), diethyl ether, dimethyl ether, and 2-methoxy-2-methylpropane.

6. The purification method according to claim 1, wherein the purity of the phosphorus-containing olefin compound salt in the purified product is 95 mass % or more.

7. A method for producing an olefin compound, comprising reacting the purified product obtained by the purification method according to claim 1 and a base to thereby obtain a reaction product containing a dephosphorized and hydrogenated olefin compound.

8. The production method according to claim 7, wherein the olefin compound is (E)-1,2-difluoroethylene.

9. The production method according to claim 7, wherein the reaction product comprises (E)-1,2-difluoroethylene and at least one member selected from the group consisting of acetylene, trifluoroethylene, pentafluoroethane (R-125), 1,1,1,2-tetrafluoroethane (R-134a), (Z)-1,2-difluoroethylene, tetrafluoroethylene, and cis- and trans-1H-nonafluoro-2-propoxyethene.

10. A solid comprising at least one phosphorus-containing olefin compound salt selected from the group consisting of: a phosphorus-containing olefin compound salt A represented by the following formula (1): ##STR00018## wherein X.sub.1 and X.sub.2 are each independently F, Cl, Br, I, or H; W.sup.+s are the same or different and each is a monovalent cation comprising PR.sub.3 or P(OR).sub.3, provided that Rs are groups having a saturated or unsaturated structure containing C and H, are optionally bonded together to form a ring, and optionally contain an atom other than C and H; three Rs included in R.sub.3 and (OR).sub.3 are optionally the same or different; and M.sup.− is a monovalent anion comprising an atom or a compound; and a phosphorus-containing olefin compound salt B represented by the following formula (2): ##STR00019## wherein X.sub.1, X.sub.2, W.sup.+, and M.sup.− are as defined above, and Y is F, Cl, Br, I, H, an alkyl group, an alkyl ether group, a fluoroalkyl group, or a fluoroalkyl ether group; and further comprising at least one compound selected from the group consisting of: (trans-2-perfluoropropoxy-1,2-difluoroethen-1-yl)(tributyl) phosphonium tetrafluoroboranuide, (cis-2-perfluoropropoxy-1,2-difluoroethen-1-yl)(tributyl) phosphonium tetrafluoroboranuide, perfluoropropoxy vinyl ether, (2,2,3,3,3 -pentafluoro-1-tributylphosphin-1-one) tetrafluoroboranuide, boron trifluoride tributylphosphine oxide, tetrafluoroboric acid, (1,2-difluoroethen-1-yl)(tributyl) phosphonium tetrafluoroboranuide), diethyl ether, dimethyl ether, and 2-methoxy-2-methylpropane.

Description

EXAMPLES

[0061] Embodiments of the present disclosure are described in more detail below based on Examples. However, the present disclosure is not limited to the scope of the Examples.

Example 1

[0062] A target olefin compound (C) (R1132(E)) was synthesized from a raw material olefin (A) (C.sub.3F.sub.7OCF=CF.sub.2) according to the following formula:

##STR00015##

[0063] Specifically, PBu.sub.3 (89.2 g, 440 mmol) was dissolved in ether (500 ml) at 5° C. While stirring this solution, the raw material olefin (A) (39.2 g, 147 mmol) was added dropwise at a temperature of 5° C. over 20 minutes to cause reaction.

[0064] After the reaction mixture was maintained at 5° C. for 2 hours, BF.sub.3OEt.sub.2 (63.3 g, 446 mmol) was added at a temperature of 5 to 20° C., and the mixture was then stirred at a temperature of 25° C. for 1.5 hours.

[0065] The upper ether layer was decanted, and the residue was washed with ether and dried in vacuum, thereby obtaining a white sticky substance (a solid containing the phosphorus-containing olefin compound salt (B)) (155.5 g). When the solid was analyzed by NMR, 16 mass % of [CF.sub.3CF.sub.2C(O)-PBu.sub.3] [BF.sub.4] was contained as an impurity.

[0066] The solid containing the phosphorus-containing olefin compound salt (B) was dissolved in ethyl acetate at 50° C., and the temperature of the solution was reduced at −0.25 ° C./min to perform reprecipitation and/or recrystallization, thereby obtaining a purified product. The purified product was extracted by suction filtration.

[0067] A 50 mass % aqueous sodium hydroxide solution was added to the purified product to react with a base. The liquid temperature was raised from 28° C. to 50° C.

[0068] The reaction product (distillate) with the base was analyzed by gas chromatogram.

[0069] The results are shown in Table 1 below.

Comparative Example 1

[0070] A target olefin compound (C) (R1132(E)) was synthesized from a raw material olefin (A) (C.sub.3F.sub.7OCF=CF.sub.2) under the same conditions as in Example 1, except that the solid containing the phosphorus-containing olefin compound salt (B) was not reprecipitated and recrystallized. That is, a white sticky substance (a solid containing the phosphorus-containing olefin compound salt (B)) was directly reacted with a base.

[0071] The results are shown in Table 1 below.

TABLE-US-00001 TABLE 1 Gas chromatogram analysis results of reaction product (distillate) with base (GC %) cis- cis- HC≡CH CF.sub.2═CFH R1132(E) R-125 R1132(Z) R-134a C.sub.3H.sub.7OCF═CFH C.sub.3H.sub.7OCF═CFH Total Comparative 1.041 8.95 82.911 0.604 1.665 1.278 0.225 0.322 96.996 Example 1 Example 1 0.167 0.689 98.611 0.02 n.d. 0.256 n.d. n.d. 99.743

[0072] As is clear from the results of Table 1, in the case of Example 1, in which the phosphorus-containing olefin compound salt (B) was purified by reprecipitation and/or recrystallization, the yield of the target olefin compound (C) (R1132(E)) was higher, and the content of isomers and other by-products was relatively lower, compared with Comparative Example 1, in which reprecipitation and/or recrystallization was not performed.