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; each W.sup.+ is the same or different and is a monovalent cation comprising PR.sub.3 or P(OR).sub.3, provided that each R is independently a group having a saturated or unsaturated structure containing C and H, each R is optionally bonded together to form a ring, and each R optionally contains an atom other than C and H; 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 in a solution, wherein after the solid is dissolved in the solvent at 45 to 60 C., the temperature of the solution is reduced at 0.25 C./min or less to thereby perform the reprecipitation and/or recrystallization.

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

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

4. The 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.

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

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

7. The method according to claim 6, wherein the olefin compound is (E)-1,2-difluoroethylene.

8. The method according to claim 6, wherein the reaction product comprises (E)-1,2-difluoroethylene and at least one compound selected from the group consisting of acetylene, trifluoroethylene, pentafluoroethane, 1,1,1,2-tetrafluoroethane, (Z)-1,2-difluoroethylene, tetrafluoroethylene, and cis-1H-nonafluoro-2-propoxyethene, and trans-1H-nonafluoro-2-propoxyethene.

9. A solid comprising: (i) 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 each independently F, Cl, Br, I, or H; each W.sup.+ is the same or different and is a monovalent cation comprising PR.sub.3 or P(OR).sub.3, provided that each R is independently a group having a saturated or unsaturated structure containing C and H, each R is optionally bonded together to form a ring, and each R optionally contains an atom other than C and H; 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 (ii) 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), dimethyl ether, and 2-methoxy-2-methylpropane.

Description

EXAMPLES

(1) 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

(2) A target olefin compound (C) (R1132(E)) was synthesized from a raw material olefin (A) (C.sub.3F.sub.7OCFCF.sub.2) according to the following formula:

(3) ##STR00015##

(4) 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.

(5) 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.

(6) 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.

(7) 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.

(8) 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.

(9) The reaction product (distillate) with the base was analyzed by gas chromatogram.

(10) The results are shown in Table 1 below.

Comparative Example 1

(11) A target olefin compound (C) (R1132(E)) was synthesized from a raw material olefin (A) (C.sub.3F.sub.7OCFCF.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.

(12) The results are shown in Table 1 below.

(13) TABLE-US-00001 TABLE 1 Gas chromatogram analysis results of reaction product (distillate) with base (GC %) cis- cis- HCCH CF.sub.2CFH R1132(E) R-125 R1132(Z) R-134a C.sub.3H.sub.7OCFCFH C.sub.3H.sub.7OCFCFH 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

(14) 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.