Method for producing hexafluoro-2-butyne

Abstract

This disclosure aims to provide a new method for producing hexafluoro-2-butyne. [Solution] A method for producing hexafluoro-2-butyne.

Description

[Technical Field]

[0001] This disclosure relates to a method for producing hexafluoro-2-butyne. [Background technology]

[0002] Patent Document 1 discloses a method for producing a perfluoroalkyne compound, which includes the step of reacting a perfluoroalkadiene compound in the presence of a catalyst to obtain a perfluoroalkyne compound; a composition containing a perfluoroalkyne compound and a perfluorocycloalkene compound; a catalyst used for reacting a perfluoroalkadiene compound to obtain a perfluoroalkyne compound; and a method for producing a catalyst used for reacting a perfluoroalkadiene compound to obtain a perfluoroalkyne compound.

[0003] Patent Document 2 discloses a method for producing a halogenated butene compound, which includes a step of dehydrofluorinating a halogenated butene compound; a method for producing a halogenated butyne compound, which includes a step of dehydrofluorinating a halogenated butene compound; and a method for producing a halogenated butyne compound, which includes a step of producing a halogenated butene compound by dehydrofluorinating a halogenated butene compound, and then producing a halogenated butyne compound by dehydrohalogenating the halogenated butene compound.

[0004] Patent Document 3 discloses a method for producing a perfluorocarbon compound, comprising the step of reacting a halogenated hydrocarbon compound in an organic solvent in the presence of an iodine-containing inorganic material and zinc or a zinc alloy to obtain a perfluorocarbon compound, and a method for producing a perfluoroalkyne compound, comprising the step of reacting a halogenated alkene compound in the presence of zinc or a zinc alloy in at least one nitrogen-containing polar organic solvent selected from the group consisting of N,N-dimethylacetamide, N,N-diisopropylformamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-3,4,5,6-tetrahydropyrimidinone, hexamethylphosphate triamide, amine compounds, pyridine compounds, and quinoline compounds to obtain a perfluoroalkyne compound. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International public access number WO2020 / 075728A1 [Patent Document 2] International public access number WO2020 / 171011A1 [Patent Document 3] International Publication Number WO2020 / 204146A1 [Overview of the project] [Problems that the invention aims to solve]

[0006] This disclosure aims to provide a new method for producing hexafluoro-2-butyne. [Means for solving the problem]

[0007] This disclosure includes the following components:

[0008] Section 1. (1) A method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3), (2) 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) (3) (3-1) In the presence of at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br); (3-2) In the presence of oxygen; or, (3-3) In the presence of water; A manufacturing method that includes a step of inducing an isomerization reaction.

[0009] Section 2. In the step of carrying out the isomerization reaction, (3) (3-1) When carrying out the step of an isomerization reaction in the presence of the olefin compound, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the olefin compound, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) shall be 99.0% by volume or more and 99.999% by volume or less. The content of the olefin compound is set to 0.001% by volume or more and 1% by volume or less. (3-2) When carrying out the isomerization reaction in the presence of oxygen, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the oxygen, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) shall be 95% by volume or more and 99.999% by volume or less. The oxygen content shall be 0.01 ppm by volume or more and 10 ppm by volume or less, (3) When carrying out the isomerization reaction in the presence of water, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the water, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) shall be 95% by volume or more and 99.999% by volume or less. The water content shall be between 0.01 ppm by volume and 50 ppm by volume. The manufacturing method described in item 1 above.

[0010] Section 3. The manufacturing method according to item 1, wherein the isomerization reaction step is carried out in the liquid phase.

[0011] Section 4. (1) 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3); (2) 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2); and (3) (3-1) at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br); (3-2) oxygen; and (3-3) water; at least one component selected from the group consisting of, A composition containing the same.

[0012] Item 5. In the composition, relative to the total amount of the composition, The content of the (1) 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) is 95% by volume or more and 99.99999% by volume or less, The content of the (2) 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) is 0.01% by volume or more and 1% by volume or less, The (3) When the composition contains (3-1) the olefin compound, the content of the olefin compound is 0.01% by volume or more and 1.5% by volume or less, When the composition contains (3-2) the oxygen, the content of the oxygen is 0.01 ppm by volume or more and 10 ppm by volume or less, or When the composition contains (3-3) the water, the content of the water is 0.01 ppm by volume or more and 30 ppm by volume or less, The composition according to the above item 4.

[0013] Item 6. The composition according to the above item 4, which is used as an etching gas, a refrigerant, a heat transfer medium, a deposit gas, a building block for organic synthesis, or a cleaning gas.

[0014] This disclosure discloses a method for producing hexafluoro-2-butyne (CF3C≡CCF3). According to this disclosure, in the production of hexafluoro-2-butyne, a step is taken to isomerize hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in the presence of an olefin compound such as heptafluorobutene (C4F7H), in the presence of oxygen, or in the presence of water. This suppresses polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne, or the generation of acid, when storing or transporting the produced hexafluoro-2-butyne-containing composition in a cylinder or the like. This suppresses a decrease in the purity of hexafluoro-2-butyne and maintains the storage stability of the hexafluoro-2-butyne-containing composition.

[0015] The hexafluoro-2-butyne-containing composition of this disclosure contains an olefin compound such as heptafluorobutene (C4F7H), oxygen, or water, and has improved storage stability. Even under harsh conditions in maritime transport such as containers (e.g., temperature rise during transport), polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed, or the generation of acid is suppressed, thereby enabling the hexafluoro-2-butyne-containing composition to be stored and transported stably. [Effects of the Invention]

[0016] This disclosure provides a new method for producing hexafluoro-2-butyne. [Modes for carrying out the invention]

[0017] In this specification, "contains" is a concept that encompasses all of "contains," "consist essentially of," and "consist of." In this specification, when a numerical range is indicated as "A to B," it means "greater than or equal to A and less than or equal to B." In this specification, when expressions such as parts and percentages are used, they represent parts by mass, parts by weight, mass%, or weight% (wt%).

[0018] [1] Method for producing hexafluoro-2-butyne The present disclosure provides a method for producing (1) 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as a raw material, which includes (2) 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) as a raw material, and by adjusting the concentrations of (3) (3-1) olefin compounds, (3-2) oxygen (O2), or (3-3) water, it is possible to suppress polymerization (dimerization, etc.) of halogenated alkyne compounds or suppress the generation of acid when producing 1,1,1,4,4,4-hexafluoro-2-butyne, thereby improving the storage stability of the crude product after the reaction.

[0019] The crude 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) obtained by the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure has its concentration of olefin compounds, oxygen (O2), or water adjusted, which suppresses decomposition reactions, polymer formation, and acid formation during storage in a tank, thereby suppressing clogging of piping and corrosion of equipment during storage.

[0020] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as disclosed herein is: 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) The process includes a step of carrying out an isomerization reaction in the presence of at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br).

[0021] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as disclosed herein is: Preferably, in the step of carrying out the isomerization reaction, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the olefin compound, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) shall be 99.0% by volume or more and 99.999% by volume or less. The content of the olefin compound shall be 0.001% by volume or more and 1% by volume or less.

[0022] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as disclosed herein is: 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) The process includes a step of carrying out an isomerization reaction in the presence of oxygen.

[0023] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as disclosed herein is: Preferably, in the step of carrying out the isomerization reaction, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the oxygen, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) shall be 95% by volume or more and 99.999% by volume or less. The oxygen content shall be between 0.01 ppm by volume and 10 ppm by volume.

[0024] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as disclosed herein is: 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) The process includes a step of carrying out an isomerization reaction in the presence of water.

[0025] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) as disclosed herein is: Preferably, in the step of carrying out the isomerization reaction, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the water, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) shall be 95% by volume or more and 99.999% by volume or less. The water content shall be between 0.01 ppm by volume and 50 ppm by volume.

[0026] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure preferably involves carrying out the isomerization reaction step in the liquid phase.

[0027] In the production of hexafluoro-2-butyne according to the present disclosure, by subjecting hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) to an isomerization reaction in the presence of (3-1) an olefin compound such as heptafluorobutene (C4F7H), (3-2) oxygen (O2), or (3-3) water, polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed when the composition containing the produced hexafluoro-2-butyne is stored in cylinders or the like, or when it is transported, or when acid is suppressed, thereby suppressing a decrease in the purity of hexafluoro-2-butyne and maintaining the storage stability of the composition containing hexafluoro-2-butyne.

[0028] In this disclosure, "conversion rate" means the ratio (mol%) of the total molar amount of compounds other than the raw material compound (such as the target compound 1,1,1,4,4,4-hexafluoro-2-butyne) contained in the effluent gas from the reactor outlet to the molar amount of the raw material compound (1,1,2,3,4,4-hexafluoro-1,3-butadiene) supplied to the reactor.

[0029] In this disclosure, "selectivity" means the ratio (mol%) of the total molar amount of the target compound (1,1,1,4,4,4-hexafluoro-2-butyne) contained in the effluent gas from the reactor outlet to the total molar amount of compounds other than the raw material compound (such as the target compound 1,1,1,4,4,4-hexafluoro-2-butyne) in the effluent gas.

[0030] (1) Raw material compound The raw material compound of this disclosure is 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2).

[0031] (2) Isomerization reaction (2-1) In the presence of an olefin compound The isomerization step of the present disclosure involves isomerizing 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in the presence of at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br) to produce 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3).

[0032] The isomerization reaction step is preferably carried out in the liquid phase.

[0033] Olefin compounds The olefin compound is at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br).

[0034] (Octafluorobutene) Octafluorobutene (C4F8) can be used in any isomer. Preferably, octafluoro-1-butene, (E / Z)-octafluoro-2-butene, (E)-octafluorobutene, (Z)-octafluorobutene, octafluorocyclobutane, pentafluorotrifluoromethylpropene, etc. are used as octafluorobutene.

[0035] Octafluorobutene may contain isomers, may be used alone, or may be used as a mixture (blend) of two or more types.

[0036] (Heptafluorobutene) Any isomer of heptafluorobutene (C4F7H) can be used. Preferably, as heptafluorobutene, 1,1,2,3,3,4,4-heptafluoro-1-butene, (E / Z)-1,1,1,2,4,4,4-heptafluoro-2-butene, (E)-1,1,1,2,4,4,4-pentafluoro-2-butene, (Z)-1,1,1,2,4,4,4-pentafluoro-2-butene, 1,1,2,3,3,4,4-heptafluoro Luoro-1-butene, 1,2,3,3,4,4,4-heptafluoro-1-butene, 1,1,3,3,4,4,4-heptafluoro-1-butene, 1,1,2,3,4,4,4-heptafluoro-1-butene, 1,3,3,3-tetrafluoro-2-(trifluoromethyl)-1-propene, 1,1,1,2,3,4,4-heptafluoro-2-butene, etc. are used.

[0037] Heptafluorobutene may contain isomers, may be used alone, or may be used in a mixture (blend) of two or more types.

[0038] (Pentafluorobutadiene) Any isomer of pentafluorobutadiene (C4F5H) can be used. Preferably, the pentafluorobutadiene used is 1,1,2,4,4-pentafluoro-1,3-butadiene, 1,3,3,4,4-pentafluorooctylcyclobutene, 3,3,4,4,4-pentafluoro-1-butyne, 1,2,3,3,4-pentafluorocyclobutene, 1,1,2,3,4-pentafluoro-1,3-butadiene, 3,3-difluoro-1-(trifluoromethyl)cyclopropene, 1,2,2,4,4-pentafluorobicyclo[1,1,0]butene, 1,1,1,4,4-pentafluoro-2-butyne, etc.

[0039] Pentafluorobutadiene may contain isomers, may be used alone, or may be used as a mixture (blend) of two or more types.

[0040] (Chloropentafluorobutadiene) Any isomer of chloropentafluorobutadiene (C4F5Cl) can be used. Preferably, the chloropentafluorobutadiene used is (E / Z)-1-chloropentafluoro-1,3-butadiene, (E)-1-chloropentafluoro-1,3-butadiene, (Z)-1-chloropentafluoro-1,3-butadiene, 1-chloro-2,3,3,4,4-pentafluorocyclobutene, 2-chloropentafluoro-1,3-butadiene, 3-chloro-1,2,3,4,4-pentafluorocyclobutene, 1-chloro-1,2,3,4,4-pentafluoro-1,3-butadiene, 1-chloro-3,3,4,4,4-pentafluoro-1-butyne, etc.

[0041] Chloropentafluorobutadiene may contain isomers, may be used alone, or may be used as a mixture (blend) of two or more isomers.

[0042] (Bromotrifluoroethylene) Bromotrifluoroethylene (C2F3Br) can be used as 1-bromo-1,2,2-trifluoroethene.

[0043] Preferred olefin compounds The olefin compounds are preferably (octafluorobutene)octafluoro-1-butene, (E / Z)-octafluoro-2-butene, (heptafluorobutene)1,1,2,3,3,4,4-heptafluoro-1-butene, (E / Z)-1,1,1,2,4,4,4-heptafluoro-2-butene, (pentafluorobutadiene)2H-pentafluoro-1,3-butadiene, (chloropentafluorobutadiene) At least one olefin compound selected from the group consisting of (E / Z)-1-chloropentafluoro-1,3-butadiene and (bromotrifluoroethylene)1-bromo-1,2,2-trifluoroethene is used, and more preferably (heptafluorobutene)(C4F7H)1,1,2,3,3,4,4-heptafluoro-1-butene, (E / Z)-1,1,1,2,4,4,4-heptafluoro-2-butene, etc.

[0044] Composition of the composition during the isomerization reaction (1,1,2,3,4,4-Hexafluoro-1,3-Butadiene) The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to the present disclosure preferably involves adjusting the content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and olefin compound to 99% by volume or more and 99.999% by volume or less in the isomerization step, more preferably to 99.5% by volume or more and 99.995% by volume or less, even more preferably to 99.9% by volume or more and 99.992% by volume or less, and particularly preferably to 99.95% by volume or more and 99.99% by volume or less.

[0045] (Olefin compounds) The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure preferably involves adjusting the content of the olefin compound to 0.001 volume% or more and 1 volume% or less relative to the total amount of the composition containing 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and the olefin compound in the isomerization step, more preferably to 0.005 volume% or more and 0.75 volume% or less, even more preferably to 0.01 volume% or more and 0.5 volume% or less, and particularly preferably to 0.05 volume% or more and 0.35 volume% or less.

[0046] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure can suppress polymerization (dimerization, etc.) of the halide alkyne compound or suppress the generation of acid by adjusting the concentration of the olefin compound contained in the raw materials, thereby improving the storage stability of the crude product after the reaction.

[0047] The crude 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) obtained by the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure has an adjusted concentration of olefin compounds in the crude product, which can suppress decomposition reactions, polymer formation, and acid formation during storage in a storage tank, thereby suppressing clogging of storage piping, corrosion of equipment, etc.

[0048] (2-2) In the presence of oxygen The isomerization step of this disclosure involves isomerizing 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in the presence of oxygen to produce 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3).

[0049] The isomerization reaction step is preferably carried out in the liquid phase.

[0050] Composition of the composition during the isomerization reaction (1,1,2,3,4,4-Hexafluoro-1,3-Butadiene) The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to the present disclosure preferably involves adjusting the content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and oxygen in the isomerization step to 95% by volume or more and 99.999% by volume or less, more preferably 96% by volume or more and 99.995% by volume or less, even more preferably 97% by volume or more and 99.992% by volume or less, and particularly preferably 98% by volume or more and 99.99% by volume or less.

[0051] (oxygen) The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure preferably involves adjusting the oxygen content in the isomerization step to 0.01 volume ppm or more and 10 volume ppm or less relative to the total amount of a composition containing 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and oxygen, more preferably to 0.1 volume ppm or more and 9.5 volume ppm or less, even more preferably to 0.5 volume ppm or more and 7.5 volume ppm or less, and particularly preferably to 1 volume ppm or more and 5 volume ppm or less.

[0052] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure can suppress polymerization (dimerization, etc.) of the halide alkyne compound or suppress the generation of acid by adjusting the oxygen concentration contained in the raw materials, thereby improving the storage stability of the crude product after the reaction.

[0053] The crude 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) obtained by the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure has an adjusted oxygen concentration in the crude material, which suppresses decomposition reactions and the formation of polymers and acids during storage in a storage tank, thereby suppressing clogging of piping and corrosion of equipment during storage.

[0054] (2-3) In the presence of water The isomerization step of this disclosure involves isomerizing 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in the presence of water to produce 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3).

[0055] The isomerization reaction step is preferably carried out in the liquid phase.

[0056] Composition of the composition during the isomerization reaction (1,1,2,3,4,4-Hexafluoro-1,3-Butadiene) The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to the present disclosure preferably involves adjusting the content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and water in the isomerization step to 95% by volume or more and 99.999% by volume or less, more preferably 96% by volume or more and 99.995% by volume or less, even more preferably 97% by volume or more and 99.992% by volume or less, and particularly preferably 98% by volume or more and 99.99% by volume or less.

[0057] (water) The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure preferably involves adjusting the water content relative to the total amount of a composition containing 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and water in the isomerization step to 0.01 volume ppm or more and 50 volume ppm or less, more preferably 0.05 volume ppm or more and 40 volume ppm or less, even more preferably 0.5 volume ppm or more and 30 volume ppm or less, and particularly preferably 1 volume ppm or more and 20 volume ppm or less.

[0058] The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure can suppress polymerization (dimerization, etc.) of the halide alkyne compound or suppress the generation of acid by adjusting the concentration of water contained in the raw materials, thereby improving the storage stability of the crude product after the reaction.

[0059] The crude 1,1,1,4,4,4-hexafluoro-2-butyne obtained after the reaction in the production method of 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) of the present disclosure has an adjusted water concentration in the crude product, which can suppress decomposition reactions, suppress the formation of polymers and acid components during storage in a storage tank, and prevent clogging of storage tank piping, corrosion of equipment, and the like.

[0060] Lewis acid catalyst (fluorinating catalyst or non-fluorinating catalyst) The step of performing an isomerization reaction of the present disclosure may preferably use a Lewis acid catalyst as the catalyst.

[0061] In the step of performing an isomerization reaction, a fluorinated Lewis acid catalyst or a non-fluorinated Lewis acid catalyst is preferably used as the catalyst.

[0062] The Lewis acid catalyst is preferably an aluminum chloride catalyst, a chromium oxide catalyst, an alumina catalyst, a silica-alumina catalyst, a zeolite catalyst, or the like. As the Lewis acid catalyst, both non-fluorinated Lewis acid catalysts and fluorinated Lewis acid catalysts can be adopted.

[0063] (Aluminum Chloride Catalyst) The aluminum chloride catalyst may be fluorinated. Fluorinated aluminum chloride can be obtained by reacting aluminum chloride with a fluorinating agent.

[0064] (Chromium Oxide Catalyst) In the chromium oxide catalyst, when chromium oxide is represented by CrOm, m is preferably 1.5<m<3, more preferably 2<m<2.75, and even more preferably 2<m<2.3. Chromium oxide is represented by CrO m ·nH2O, the value of n is preferably 3 or less, and more preferably 1 to 1.5.

[0065] Fluorinated chromium oxide catalysts are preferably prepared by fluorinating a chromium oxide catalyst. Fluorination is preferably carried out using HF, fluorocarbons, etc. Fluorinated chromium oxide catalysts are synthesized, for example, according to the method described in Japanese Patent Application Publication No. 05-146680.

[0066] (Alumina catalyst) The alumina catalyst is preferably α-alumina, activated alumina, etc. The activated alumina is preferably ρ-alumina, χ-alumina, κ-alumina, η-alumina, pseudo-γ-alumina, γ-alumina, σ-alumina, θ-alumina, etc. Alternatively, it may be a composite oxide containing alumina and another compound.

[0067] The composite oxide is preferably a silica-alumina catalyst. The silica-alumina catalyst is a composite oxide catalyst containing silica (SiO2) and alumina (Al2O3), where the total amount of silica and alumina is 100% by mass, and the silica content is preferably 20% to 90% by mass, and more preferably 50% to 80% by mass.

[0068] Alumina catalysts and silica-alumina catalysts exhibit stronger activity upon fluorination. Preferably, alumina catalysts are pre-fluorinated and used as fluorinated alumina catalysts before being used in catalytic reactions. Similarly, silica-alumina catalysts are pre-fluorinated and used as fluorinated silica-alumina catalysts before being used in catalytic reactions.

[0069] For fluorinating alumina catalysts and silica-alumina catalysts, fluorinating agents such as inorganic fluorinating agents like F2 and HF, or fluorocarbon-based organic fluorinating agents like hexafluoropropene are preferably used.

[0070] A preferred method for fluorinating alumina catalysts and silica-alumina catalysts is to fluorinate them by flowing a fluorinating agent through them at a temperature of approximately -20°C to 400°C and a pressure of -50kPa to 2.0MPa.

[0071] The preferred methods for fluorinating alumina catalysts and silica-alumina catalysts are to fluorinate by circulating a fluorinating agent under atmospheric pressure at a temperature of approximately 25°C to 400°C, or to fluorinate by confining the fluorinating agent under a pressure of -50kPa to 2,000kPa at a temperature of approximately -20°C to 400°C.

[0072] (Zeolite catalyst) The zeolite catalyst employs a wide range of known types of zeolites. The zeolite catalyst is preferably a crystalline hydrated aluminosilicate of an alkali metal or alkaline earth metal. The crystalline form of the zeolite is preferably type A, type X, type LSX, etc. The alkali metal or alkaline earth metal in the zeolite is preferably potassium, sodium, calcium, lithium, etc.

[0073] Zeolite catalysts exhibit stronger activity upon fluorination. Preferably, zeolite catalysts are pre-fluorinated and used as fluorinated zeolite catalysts before being used in catalytic reactions.

[0074] The fluorinating agent used to fluorinate the zeolite catalyst is preferably an inorganic fluorinating agent such as F2 or HF, or a fluorocarbon-based organic fluorinating agent such as hexafluoropropene.

[0075] A preferred method for fluorinating a zeolite catalyst is to fluorinate it by flowing a fluorinating agent through it at a temperature of approximately -20°C to 400°C and a pressure of -50kPa to 2.0MPa.

[0076] A preferred method for fluorinating a zeolite catalyst is to fluorinate it by passing a fluorinating agent through it under atmospheric pressure at a temperature of approximately 25°C to 400°C.

[0077] (Titanium dioxide catalyst) The titanium oxide catalyst is preferably composed mainly of titanium dioxide, but may also contain one or more nonvolatile substances such as other metal oxides, hydroxides, sulfates, nitrates, phosphates, and sulfides. The titanium oxide catalyst preferably contains 70% by mass or more of titanium dioxide.

[0078] Titanium dioxide is preferably anatase-type titanium dioxide, and its specific surface area is preferably 5 m². 2 / g~100m 2 The filtration rate is / g, and the pore volume is preferably 0.2 mL / g to 0.4 mL / g. The catalyst is preferably molded into a spherical shape. For example, commercially available catalysts such as CS-200, CS-300, and CS-950 can be used.

[0079] As a catalyst, a fluorinated titanium oxide catalyst is preferably used because it exhibits high isomerization reaction activity, increases the conversion rate of the reaction, reduces catalyst degradation, and suppresses catalyst degradation even when the isomerization reaction is carried out over a long period of time.

[0080] (Iron oxide catalyst) Preferably, an iron catalyst such as iron oxide, iron fluoride oxide, or iron fluoride is used as the iron catalyst.

[0081] The catalyst may be used as a single catalyst, or as a mixture (blend) of two or more catalysts.

[0082] (Fluorination of catalysts) The isomerization reaction step of this disclosure preferably uses a fluorinated metal oxide catalyst as the catalyst. By fluorinating the catalyst, the catalyst exhibits strong activity, reducing catalyst degradation, and by adjusting the pore volume, catalyst degradation can be suppressed even when the isomerization reaction is carried out over a long period of time.

[0083] A preferred method for fluorinating a metal oxide catalyst involves reacting the metal oxide with a fluorinating agent. Specifically, the fluorinating agent is passed through the metal oxide to fluorinate it. The metal oxide used in this process is the metal oxide that constitutes the fluorinated metal oxide.

[0084] Preferably, the fluorinating agents are hydrofluorocarbons (R23: trifluoromethane, R32: difluoromethane, R41: monofluoromethane), hydrochlorofluorocarbons (R22: chlorodifluoromethane, R21: dichloromonofluoromethane), chlorofluorocarbons (R13: chlorotrifluoromethane, R11: trichloromonofluoromethane), etc. Compared to hydrogen fluoride, fluorinating agents tend to increase the pore volume of the fluorinated metal oxide catalyst, making it easier to reduce catalyst degradation and suppress catalyst degradation when the above isomerization reaction is carried out for a long time. Fluorinating agents can be used alone or in combination of two or more types.

[0085] There are no particular restrictions on the conditions for fluorination, but from the viewpoint of easily reducing catalyst degradation and suppressing catalyst degradation even when the isomerization reaction is carried out over a long period of time, the temperature is preferably -20°C to 400°C, and more preferably 0°C to 200°C.

[0086] For similar reasons, the conditions for fluorination are preferably a pressure of -50 kPa to 2,000 kPa, and more preferably 0 kPa to 1,000 kPa.

[0087] For similar reasons, the fluorination conditions are preferably 0.1 to 24 hours, and more preferably 1 to 12 hours.

[0088] (Examples of catalyst use) The isomerization reaction step of this disclosure preferably uses a fluorinated or non-fluorinated aluminum chloride catalyst, a fluorinated or non-fluorinated chromium oxide catalyst, a fluorinated or non-fluorinated alumina catalyst, etc., from the viewpoint of conversion rate, selectivity, and yield.

[0089] When a fluorinated or non-fluorinated Lewis acid catalyst is used, the catalyst is preferably supported on a carrier. The carrier is preferably carbon, alumina (Al₂O₃), zirconia (ZrO₂), silica (SiO₂), titania (TiO₂), or the like. As the carbon, activated carbon, amorphous carbon, graphite, diamond, or the like is used.

[0090] In the step of performing the isomerization reaction, when the raw material compound is subjected to the isomerization reaction in the presence of the catalyst, the raw material compound is preferably brought into contact with the catalyst in a solid state (solid phase). The catalyst can be used in a powdery form or a pellet form, and a powdery form is preferably employed for a liquid phase reaction.

[0091] The specific surface area of the catalyst measured by the BET method (hereinafter sometimes referred to as "BET specific surface area") is preferably usually 10 m 2 / g to 3,000 m 2 / g, more preferably 10 m 2 / g to 2,500 m 2 / g, still more preferably 20 m 2 / g to 2,000 m 2 / g, and particularly preferably 30 m 2 / g to 1,500 m 2 / g. When the BET specific surface area of the catalyst is within the above range, the density of the catalyst particles does not become excessively low, so that the isomerization reaction can proceed efficiently, and the target compound can be obtained with a higher conversion rate, yield, and / or high selectivity.

[0092] Reaction temperature of isomerization reaction In the step of performing the isomerization reaction of the present disclosure, the lower limit of the reaction temperature is preferably -20°C or higher, more preferably 0°C or higher, and still more preferably 20°C or higher, from the viewpoint of allowing the isomerization reaction to proceed more efficiently from the raw material compound, further improving the conversion rate, and obtaining the target compound with higher selectivity.

[0093] In the isomerization reaction step, the upper limit of the reaction temperature is preferably 400°C or lower, more preferably 200°C or lower, and even more preferably 100°C or lower, from the viewpoint of allowing the isomerization reaction to proceed more efficiently, improving the conversion rate, obtaining the target compound with higher selectivity, and further suppressing the decrease in selectivity due to the decomposition or polymerization of the reaction product.

[0094] The isomerization reaction step is preferably carried out at a reaction temperature of room temperature (around 25°C).

[0095] In the isomerization reaction process, the reaction time can be set as appropriate.

[0096] Even when using a batch reaction method, the contact time can be set as appropriate.

[0097] The above contact time refers to the time during which the raw material compound (substrate) and the catalyst are in contact.

[0098] Reaction pressure of isomerization reaction In the isomerization reaction step of this disclosure, the reaction pressure for the isomerization reaction is preferably -0.05 MPa to 2 MPa, more preferably -0.01 MPa to 1 MPa, and even more preferably atmospheric pressure to 0.5 MPa, from the viewpoint of enabling the isomerization reaction to proceed more efficiently.

[0099] In this disclosure, unless otherwise specified, pressure shall be gauge pressure.

[0100] Reaction vessel for isomerization reaction The isomerization reaction step described herein involves introducing the raw material compound and the catalyst to carry out the isomerization reaction. The reactor used for this reaction is not particularly limited in shape or structure, as long as it can withstand the above-mentioned temperature and pressure. Preferably, the reactor for the isomerization reaction is a vertical reactor, a horizontal reactor, a multi-tube reactor, etc. Preferably, the material of the reactor for the isomerization reaction is glass, stainless steel, iron, nickel, iron-nickel alloy, etc.

[0101] Liquid-phase reaction The isomerization reaction step described herein can preferably be carried out by either a flow-through or batch-through method, in which the raw material compound (substrate) is continuously charged into the reactor and the target compound is continuously withdrawn from the reactor by a liquid-phase reaction.

[0102] Since the isomerization reaction is inhibited if the target compound remains in the reactor, the reaction is preferably carried out in a flow-through manner.

[0103] liquid phase continuous flow system The isomerization reaction step described herein is preferably carried out in the liquid phase, and more preferably in a liquid-phase continuous flow system using a fixed-bed reactor. The liquid-phase continuous flow system simplifies the equipment and operation, and is also economically advantageous.

[0104] The isomerization reaction is carried out under an inert gas atmosphere, hydrogen fluoride gas atmosphere, etc., in order to suppress catalyst degradation. The inert gas is preferably nitrogen, helium, argon, etc. Among the inert gases, nitrogen is preferably used from the viewpoint of reducing costs. The concentration of the inert gas is preferably 0 mol% to 50 mol% of the gaseous components introduced into the reactor.

[0105] In the isomerization reaction process, the target compound can be obtained with higher selectivity by appropriately adjusting the reaction temperature and reaction time (contact time) according to the catalyst.

[0106] Purification process In the isomerization reaction step described herein, after the isomerization reaction is completed, the target compound can be obtained by purification treatment according to conventional methods as necessary.

[0107] (3) Target compound The compound of interest of this disclosure is 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3).

[0108] In the isomerization step, the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) is reacted with the starting compound, and the two CC double bonds in the starting compound are replaced by one CC triple bond, producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3).

[0109] [2] Compositions containing hexafluoro-2-butyne (2-1) The compositions of this disclosure are (1) 1,1,1,4,4,4-Hexafluoro-2-butyne (CF3C≡CCF3); (2) 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2); (3)(3-1) Contains at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br).

[0110] In the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to the present disclosure, in the isomerization step, the product may be obtained in the form of a composition containing, in addition to the isomerized 1,1,1,4,4,4-hexafluoro-2-butyne of the target compound, the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2), and at least one olefin compound selected from the group consisting of octafluorobutene (C4F8), heptafluorobutene (C4F7H), pentafluorobutadiene (C4F5H), chloropentafluorobutadiene (C4F5Cl), and bromotrifluoroethylene (C2F3Br) used in the isomerization step.

[0111] Preferably, in the composition, with respect to the total amount of the composition, The content of 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) is 97% by volume or more and 99.99999% by volume or less. The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) is 0.01% by volume or more and 1% by volume or less. The content of the olefin compound is 0.01% by volume or more and 1.5% by volume or less.

[0112] The hexafluoro-2-butyne-containing composition of this disclosure contains an olefin compound such as heptafluorobutene (C4F7H), which improves storage stability. Even under harsh conditions during maritime transport in containers, such as temperature increases during transport, polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed, as is the generation of acid. This makes it possible to stably store and transport the hexafluoro-2-butyne-containing composition.

[0113] (Content of 1,1,1,4,4,4-hexafluoro-2-butyne) The compositions of this disclosure preferably contain 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) in an amount of 95% by volume or more and 99.99999% by volume or less, more preferably 96% by volume or more and 99.9999% by volume or less, even more preferably 97% by volume or more and 99.9995% by volume or less, and particularly preferably 99.8% by volume or more and 99.999% by volume or less.

[0114] (Content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene) Preferably, the composition of the present disclosure contains 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in an amount of 0.01% by volume or more and 1% by volume or less, more preferably 0.05% by volume or more and 0.95% by volume or less, even more preferably 0.1% by volume or more and 0.90% by volume or less, and particularly preferably 0.15% by volume or more and 0.85% by volume or less.

[0115] (Olefin compound content) Preferably, the composition of the present disclosure has an olefin compound content (or total amount of olefin compounds if the composition contains one or more olefin compounds) of 0.01% by volume or more and 1.5% by volume or less, more preferably 0.03% by volume or more and 1.0% by volume or less, even more preferably 0.05% by volume or more and 0.5% by volume or less, and particularly preferably 0.07% by volume or more and 0.20% by volume or less.

[0116] (2-2) Compositions of the present disclosure, (1) 1,1,1,4,4,4-Hexafluoro-2-butyne (CF3C≡CCF3); (2) 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2); (3)(3-2) Contains oxygen.

[0117] In the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure, in the isomerization step, the product may be obtained in the form of a composition containing the isomerized 1,1,1,4,4,4-hexafluoro-2-butyne of the target compound, as well as the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and oxygen (O2) used in the isomerization step.

[0118] Preferably, in the composition, with respect to the total amount of the composition, The content of 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) is 95% by volume or more and 99.99999% by volume or less. The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) is 0.01% by volume or more and 1% by volume or less. The oxygen content is between 0.01 ppm by volume and 10 ppm by volume.

[0119] The hexafluoro-2-butyne-containing composition of this disclosure contains oxygen and has improved storage stability. Even under harsh conditions in maritime transport such as containers (including temperature increases during transport), polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed, or the generation of acid is suppressed. As a result, the hexafluoro-2-butyne-containing composition can be stored and transported stably.

[0120] (Content of 1,1,1,4,4,4-hexafluoro-2-butyne) The compositions of this disclosure preferably contain 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) in an amount of 95% by volume or more and 99.99999% by volume or less, more preferably 96% by volume or more and 99.9999% by volume or less, even more preferably 97% by volume or more and 99.9995% by volume or less, and particularly preferably 98% by volume or more and 99.999% by volume or less.

[0121] (Content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene) Preferably, the composition of the present disclosure contains 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in an amount of 0.01% by volume or more and 1% by volume or less, more preferably 0.05% by volume or more and 0.95% by volume or less, even more preferably 0.1% by volume or more and 0.90% by volume or less, and particularly preferably 0.15% by volume or more and 0.85% by volume or less.

[0122] (Oxygen content) Preferably, the composition of this disclosure has an oxygen content of 0.01 volume ppm or more and 10 volume ppm or less relative to the total amount of the composition, more preferably 0.1 volume ppm or more and 9.5 volume ppm or less, even more preferably 0.5 volume ppm or more and 7.5 volume ppm or less, and particularly preferably 1 volume ppm or more and 5 volume ppm or less.

[0123] (2-3) Compositions of the present disclosure, (1) 1,1,1,4,4,4-Hexafluoro-2-butyne (CF3C≡CCF3); (2) 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF2=CF-CF=CF2); (3) (3-3) Contains water.

[0124] In the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure, in the isomerization step, the product may be obtained in the form of a composition containing the isomerized 1,1,1,4,4,4-hexafluoro-2-butyne of the target compound, as well as the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) and water used in the isomerization step.

[0125] Preferably, in the composition, with respect to the total amount of the composition, The content of 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) is 95% by volume or more and 99.99999% by volume or less. The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) is 0.01% by volume or more and 1% by volume or less. The water content is between 0.01 ppm by volume and 30 ppm by volume.

[0126] The hexafluoro-2-butyne-containing composition of this disclosure contains water and has improved storage stability. Even under harsh conditions during maritime transport such as containers (including temperature increases during transport), polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed, as is the generation of acid. This makes it possible to stably store and transport the hexafluoro-2-butyne-containing composition.

[0127] (Content of 1,1,1,4,4,4-hexafluoro-2-butyne) The compositions of this disclosure preferably contain 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) in an amount of 95% by volume or more and 99.99999% by volume or less, more preferably 96% by volume or more and 99.9999% by volume or less, even more preferably 97% by volume or more and 99.9995% by volume or less, and particularly preferably 98% by volume or more and 99.999% by volume or less.

[0128] (Content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene) Preferably, the composition of the present disclosure contains 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in an amount of 0.01% by volume or more and 1% by volume or less, more preferably 0.05% by volume or more and 0.95% by volume or less, even more preferably 0.1% by volume or more and 0.90% by volume or less, and particularly preferably 0.15% by volume or more and 0.85% by volume or less.

[0129] (Water content) The compositions of this disclosure preferably have a water content of 0.01 ppm or more and 30 ppm or less relative to the total amount of the composition, more preferably 0.1 ppm or more and 25 ppm or less, even more preferably 0.5 ppm or more and 20 ppm or less, and particularly preferably 1 ppm or more and 10 ppm or less.

[0130] [3] Uses of compositions containing hexafluoro-2-butin The compositions of this disclosure are preferably used as etching gases, refrigerants, heat transfer media, deposit gases, building blocks for organic synthesis, or cleaning gases.

[0131] The composition is preferably used as an etching gas, refrigerant, heat transfer medium, etc., for forming cutting-edge microstructures such as semiconductors and liquid crystals. The composition can also be effectively utilized in various applications such as a deposit gas, building block for organic synthesis, and cleaning gas.

[0132] Deposit gas is a gas used to deposit an etching-resistant polymer layer.

[0133] Organic synthesis building blocks refer to substances that can serve as precursors for compounds with highly reactive skeletons. When a composition containing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) is reacted with a fluorine-containing organosilicon compound such as CF3Si(CH3)3, it is possible to introduce fluoroalkyl groups such as CF3 groups and convert the mixture into substances that can serve as detergents or fluorine-containing pharmaceutical intermediates. [Examples]

[0134] The present invention will be described in detail below using examples and comparative examples. However, the present invention is not limited to these.

[0135] (Example 1) In the presence of an olefin compound [1] Preparation of hexafluoro-2-butyne Starting compound: 1,1,2,3,4,4-Hexafluoro-1,3-Butadiene (CF2=CF-CF=CF2) Target compound: 1,1,1,4,4,4-Hexafluoro-2-butyne (CF3C≡CCF3) Olefin compounds: Octafluorobutene (C4F8): Octafluoro-1-butene, (E / Z)-octafluoro-2-butene Heptafluorobutene (C4F7H):1,1,2,3,3,4,4-heptafluoro-1-butene, (E / Z)-1,1,1,2,4,4,4-heptafluoro-2-butene Pentafluorobutadiene (C4F5H):2H-pentafluoro-1,3-butadiene Chloropentafluorobutadiene (C4F5Cl):(E / Z)-1-chloropentafluoro-1,3-butadiene Bromotrifluoroethylene (C2F3Br):1-bromo-1,2,2-trifluoroethene

[0136] Gas chromatography: Shimadzu Corporation, product name "GC-2014" NMR: Manufactured by JEOL, product name "400YH"

[0137] (1) Isomerization reaction by liquid-phase reaction In the liquid-phase flow reaction, the pressure was set to atmospheric pressure, and 1,1,2,3,4,4-hexafluoro-1,3-butadiene (the starting compound) was introduced into the reactor in the presence of an olefin compound, such that the molar ratio of Lewis acid catalyst to starting compound (Lewis acid catalyst / starting compound) was 0.01, 0.1, and 0.3.

[0138] The reaction was carried out in the liquid phase.

[0139] The catalyst was added to a SUS (stainless steel) vessel, which served as the reactor. After drying under a nitrogen atmosphere, the pressure was reduced to a vacuum and the temperature was raised to 25°C. Then, the fluorinating agent R22 (chlorodifluoromethane) was introduced. Subsequently, the temperature was lowered to 25°C (room temperature) to start the fluorination reaction. After that, the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene was introduced in a molar ratio of 0.1.

[0140] The reactor was set to 25°C (room temperature), and the isomerization reaction was started.

[0141] After the reaction began, the gas was collected.

[0142] After the reaction was complete, mass spectrometry was performed using gas chromatography-mass spectroscopy (GC / MS), and structural analysis was performed using NMR spectroscopy to obtain NMR spectra. The formation of the target compound, 1,1,1,4,4,4-hexafluoro-2-butyne, was confirmed by mass spectrometry and structural analysis. ND: Not Detected

[0143] [Table 1]

[0144] [Table 2]

[0145] [Table 3]

[0146] [2] Storage stability of compositions containing hexafluoro-2-butyne In the example manufacturing method, by adjusting the concentration of the olefin compound contained in the raw materials, it was possible to suppress the polymerization (dimerization, etc.) of the target compound 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) or to suppress the generation of acid.

[0147] The crude 1,1,1,4,4,4-hexafluoro-2-butyne obtained by the production method in the example had its concentration of olefin compounds adjusted, and the storage stability of the crude 1,1,1,4,4,4-hexafluoro-2-butyne after reaction was improved during storage in a storage tank.

[0148] (Example 2) In the presence of oxygen [1] Preparation of hexafluoro-2-butyne Starting compound: 1,1,2,3,4,4-Hexafluoro-1,3-Butadiene (CF2=CF-CF=CF2) Target compound: 1,1,1,4,4,4-Hexafluoro-2-butyne (CF3C≡CCF3) oxygen

[0149] The raw material compounds and the target compounds were analyzed using gas chromatography (GC-2014, manufactured by Shimadzu Corporation, with an FID detector) and NMR (400YH, manufactured by JEOL).

[0150] Oxygen was analyzed using gas chromatography: Shimadzu Corporation, product name "GC-2030", detector BID.

[0151] (1) Isomerization reaction by liquid-phase batch reaction In the liquid-phase reaction, the pressure was set to atmospheric pressure, and 1,1,2,3,4,4-hexafluoro-1,3-butadiene (the starting compound) was introduced into the reactor in the presence of oxygen, such that the molar ratio of Lewis acid catalyst to starting compound (Lewis acid catalyst / starting compound) was 0.01, 0.1, and 0.3.

[0152] The reaction was carried out using a liquid-phase batch reaction.

[0153] The catalyst was added to a SUS (stainless steel) vessel, which served as the reactor. After drying under a nitrogen atmosphere, the pressure was reduced to a vacuum and the temperature was raised to 25°C. Then, the fluorinating agent R22 (chlorodifluoromethane) was introduced. Subsequently, the temperature was lowered to 25°C (room temperature) to start the fluorination reaction. After that, the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene was introduced in a molar ratio of 0.1.

[0154] The reactor was heated to 25°C (room temperature) or 100°C to start the isomerization reaction.

[0155] After the reaction was complete, the gas was collected using conventional methods.

[0156] After the reaction was complete, mass spectrometry was performed using gas chromatography-mass spectroscopy (GC / MS), and structural analysis was performed using NMR spectroscopy to obtain NMR spectra. The formation of the target compound, 1,1,1,4,4,4-hexafluoro-2-butyne, was confirmed by mass spectrometry and structural analysis.

[0157] [Table 4]

[0158] [Table 5]

[0159] [Table 6]

[0160] [2] Storage stability of compositions containing hexafluoro-2-butyne The manufacturing method in the example was able to suppress the polymerization (dimerization, etc.) of the target compound 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) or suppress the generation of acid by adjusting the oxygen concentration contained in the raw materials.

[0161] The crude 1,1,1,4,4,4-hexafluoro-2-butyne obtained by the manufacturing method in the example had its oxygen concentration adjusted, and the storage stability of the crude 1,1,1,4,4,4-hexafluoro-2-butyne after the reaction was improved during storage in a storage tank.

[0162] (Example 3) In the presence of water [1] Preparation of hexafluoro-2-butyne Starting compound: 1,1,2,3,4,4-Hexafluoro-1,3-Butadiene (CF2=CF-CF=CF2) Target compound: 1,1,1,4,4,4-Hexafluoro-2-butyne (CF3C≡CCF3) water

[0163] The raw material compounds and the target compounds were analyzed using gas chromatography (GC-2014, manufactured by Shimadzu Corporation, with an FID detector) and NMR (400YH, manufactured by JEOL).

[0164] Moisture content was analyzed using a moisture analyzer; either a quartz oscillator process moisture analyzer (QMA) manufactured by Michel Japan Co., Ltd., or a CRDS manufactured by TIGER OPTICS Co., Ltd.

[0165] (1) Isomerization reaction by liquid-phase batch reaction In the liquid-phase flow reaction, the pressure was set to atmospheric pressure, and 1,1,2,3,4,4-hexafluoro-1,3-butadiene (the starting compound) was introduced into the reactor in the presence of water, such that the molar ratio of Lewis acid catalyst to starting compound (Lewis acid catalyst / starting compound) was 0.01, 0.1, and 0.3.

[0166] The reaction was carried out in a liquid-phase batch process.

[0167] The catalyst was added to a SUS (stainless steel) vessel, which served as the reactor. After drying under a nitrogen atmosphere, the pressure was reduced to a vacuum and the temperature was raised to 25°C. Then, the fluorinating agent R22 (chlorodifluoromethane) was introduced. Subsequently, the temperature was lowered to 25°C (room temperature) to start the fluorination reaction. After that, the starting compound 1,1,2,3,4,4-hexafluoro-1,3-butadiene was introduced in a molar ratio of 0.1.

[0168] The reactor was heated to 25°C (room temperature) or 100°C to start the isomerization reaction.

[0169] After the reaction was complete, the gas was collected using conventional methods.

[0170] After the reaction was complete, mass spectrometry was performed using gas chromatography-mass spectroscopy (GC / MS), and structural analysis was performed using NMR spectroscopy to obtain NMR spectra. The formation of the target compound, 1,1,1,4,4,4-hexafluoro-2-butyne, was confirmed by mass spectrometry and structural analysis.

[0171] [Table 7]

[0172] [Table 8]

[0173] [Table 9]

[0174] [2] Storage stability of compositions containing hexafluoro-2-butyne In the example manufacturing method, by adjusting the concentration of water contained in the raw materials, it was possible to suppress the polymerization (dimerization, etc.) of the target compound 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) or to suppress the generation of acid.

[0175] The crude 1,1,1,4,4,4-hexafluoro-2-butyne obtained by the manufacturing method in the example had its water concentration adjusted, and the storage stability of the crude 1,1,1,4,4,4-hexafluoro-2-butyne after the reaction was improved during storage in a storage tank.

[0176] [3] Industrial applicability The method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure can suppress polymerization (dimerization, etc.) of the halide alkyne compound or suppress the generation of acid by adjusting the concentration of at least one component selected from the group consisting of olefin compounds, oxygen (O2), and water contained in the raw materials, thereby improving the storage stability of the crude product after the reaction.

[0177] The crude 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) obtained by the method for producing 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) according to this disclosure has its concentration of at least one component selected from the group consisting of olefin compounds, oxygen (O2), and water adjusted. This suppresses decomposition reactions and the formation of polymers and acids during storage in a storage tank, thereby suppressing clogging of piping and corrosion of equipment during storage.

[0178] In the production of hexafluoro-2-butyne according to this disclosure, by undergoing an isomerization reaction of hexafluoro-1,3-butadiene (CF2=CF-CF=CF2) in the presence of an olefin compound such as heptafluorobutene (C4F7H), in the presence of oxygen, or in the presence of water, when the composition containing the produced hexafluoro-2-butyne is stored in a cylinder or the like or transported, polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed, or the generation of acid is suppressed, thereby suppressing a decrease in the purity of hexafluoro-2-butyne and maintaining the storage stability of the composition containing hexafluoro-2-butyne.

[0179] The hexafluoro-2-butyne-containing composition of this disclosure contains at least one component selected from the group consisting of olefin compounds such as heptafluorobutene (C4F7H), oxygen (O2), and water, and has improved storage stability. Even under harsh conditions in maritime transport such as containers (such as temperature increases during transport), polymerization (formation of polymers) or decomposition (formation of decomposition products) of hexafluoro-2-butyne is suppressed, or the generation of acid is suppressed, thereby enabling the hexafluoro-2-butyne-containing composition to be stored and transported stably.

Claims

1. (1) 1,1,1,4,4,4-Hexafluoro-2-butyne (CF 3 C≡CCF 3 A method for manufacturing ) (2) 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF 2 =CF-CF definition CF 2 )of, （3） (3-1) Octafluorobutene (C 4 F 8 ), heptafluorobutene (C 4 F 7 H), pentafluorobutadiene (C 4 F 5 H), chloropentafluorobutadiene (C 4 F 5 Cl), and bromotrifluoroethylene (C 2 F 3 Br) in the presence of at least one olefin compound selected from the group consisting of; (3-2) In the presence of oxygen; or, (3-3) In the presence of water; This includes a step of causing an isomerization reaction. In the step of carrying out the isomerization reaction, (3) above (3-1) When carrying out the step of an isomerization reaction in the presence of the olefin compound, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) and the olefin compound, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) shall be 99.0% by volume or more and 99.999% by volume or less. The content of the olefin compound is set to 0.001% by volume or more and 1% by volume or less. (3-2) When carrying out the isomerization reaction in the presence of oxygen, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) and the oxygen, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) shall be 95% by volume or more and 99.999% by volume or less. The oxygen content shall be 0.01 ppm by volume or more and 10 ppm by volume or less, (3-3) When carrying out the isomerization reaction in the presence of water, With respect to the total amount of the composition containing the 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) and the water, The content of 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) shall be 95% by volume or more and 99.999% by volume or less. The water content shall be 0.01 ppm by volume or more and 50 ppm by volume or less. The isomerization reaction step is carried out in the liquid phase. Manufacturing method.

2. (1) 1,1,1,4,4,4-Hexafluoro-2-butyne (CF 3 C≡CCF 3 ); (2) 1,1,2,3,4,4-Hexafluoro-1,3-butadiene (CF 2 =CF-CF definition CF 2 );and, （3） (3-1) Octafluorobutene (C 4 F 8 ), heptafluorobutene (C 4 F 7 H), pentafluorobutadiene (C 4 F 5 H), chloropentafluorobutadiene (C 4 F 5 Cl), and bromotrifluoroethylene (C) 2 F 3 At least one olefin compound selected from the group consisting of Br; (3-2) Oxygen; and, (3-3) Water; at least one component selected from the group consisting of these, It contains, In the above composition, with respect to the total amount of the composition, The content of (1) 1,1,1,4,4,4-hexafluoro-2-butyne (CF3C≡CCF3) is 95% by volume or more and 99.99999% by volume or less. The content of (2) 1,1,2,3,4,4-hexafluoro-1,3-butadiene (CF₂=CF-CF=CF₂) is 0.01% by volume or more and 1% by volume or less. (3) above When the composition contains (3-1) the olefin compound, the content of the olefin compound is 0.01% by volume or more and 1.5% by volume or less. When the composition (3-2) contains the oxygen, the oxygen content is 0.01 ppm by volume or more and 10 ppm by volume or less, When the composition contains (3-3) the water, the water content is 0.01 ppm by volume or more and 30 ppm by volume or less. Used as an etching gas, refrigerant, heat transfer medium, deposit gas, building block for organic synthesis, or cleaning gas. composition.

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