Disclosed is a process for the preparation of cis-1,1,1,4,4,4-hexafluoro-2-butene comprising contacting 1,1,1-trifluorotrichloroethane with hydrogen in the presence of a catalyst comprising ruthenium to produce a product mixture comprising 1316mxx, recovering said 1316mxx as a mixture of Z- and E-isomers, contacting said 1316mxx with hydrogen, in the presence of a catalyst selected from the group consisting of copper on carbon, nickel on carbon, copper and nickel on carbon and copper and palladium on carbon, to produce a second product mixture, comprising E- or Z-CFC-1326mxz, and subjecting said second product mixture to a separation step to provide E- or Z-1326mxz. The E- or Z-1326mxz can be dehydrochlorinated in an aqueous basic solution with an alkali metal hydroxide in the presence of a phase transfer catalyst to produce hexafluoro-2-butyne, which can then be selectively hydrogenated to produce Z-1,1,1,4,4,4-hexafluoro-2-butene using either Lindlar's catalyst, or a palladium catalyst further comprising a lantanide element or silver.

Disclosed is a process for the preparation of cis-1,1,1,4,4,4-hexafluoro-2-butene comprising contacting 1,1,1-trifluorotrichloroethane with hydrogen in the presence of a catalyst comprising ruthenium to produce a product mixture comprising 1316mxx, recovering said 1316mxx as a mixture of Z- and E-isomers, contacting said 1316mxx with hydrogen, in the presence of a catalyst selected from the group consisting of copper on carbon, nickel on carbon, copper and nickel on carbon and copper and palladium on carbon, to produce a second product mixture, comprising E- or Z-CFC-1326mxz, and subjecting said second product mixture to a separation step to provide E- or Z-1326mxz. The E- or Z-1326mxz can be dehydrochlorinated in an aqueous basic solution with an alkali metal hydroxide in the presence of a phase transfer catalyst to produce hexafluoro-2-butyne, which can then be selectively hydrogenated to produce Z-1,1,1,4,4,4-hexafluoro-2-butene using either Lindlar's catalyst, or a palladium catalyst further comprising a lantanide element or silver.

A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with hydrogen fluoride in the vapor phase in the presence of a fluorination catalyst comprising a metal halide to produce E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene further comprises contacting E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene with base to produce 1,1,1,4,4,4-hexafluoro-2-butyne, and subsequently hydrogenating hexafluoro-2-butyne to produce Z-1,1,1,4,4,4-hexafluoro-2-butene.

A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with hydrogen fluoride in the vapor phase in the presence of a fluorination catalyst comprising a metal halide to produce E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene further comprises contacting E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene with base to produce 1,1,1,4,4,4-hexafluoro-2-butyne, and subsequently hydrogenating hexafluoro-2-butyne to produce Z-1,1,1,4,4,4-hexafluoro-2-butene.

Processes for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene and intermediates for producing same. A process for producing 2-chloro-1,1,1,4,4,4-hexafluorobutane comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the liquid phase in the presence of a fluorination catalyst. A process for producing 2,2-dichloro-1,1,1,4,4,4-hexafluorobutane comprises contacting 2-chloro-1,1,1,4,4,4-hexafluorobutane with a chlorine source. A process for producing 1,1,1,4,4,4-hexafluoro-2-butyne comprises contacting 2,2-dichloro-1,1,1,4,4,4-hexafluorobutane with a base. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen.

Processes for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene and intermediates for producing same. A process for producing 2-chloro-1,1,1,4,4,4-hexafluorobutane comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the liquid phase in the presence of a fluorination catalyst. A process for producing 2,2-dichloro-1,1,1,4,4,4-hexafluorobutane comprises contacting 2-chloro-1,1,1,4,4,4-hexafluorobutane with a chlorine source. A process for producing 1,1,1,4,4,4-hexafluoro-2-butyne comprises contacting 2,2-dichloro-1,1,1,4,4,4-hexafluorobutane with a base. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen.

Processes for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene and intermediates for producing same. A process for producing 2-chloro-1,1,1,4,4,4-hexafluorobutane comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the liquid phases. A process for producing E-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 2-chloro-1,1,1,4,4,4-hexafluorobutane with base. A process for producing 2,3-dichloro-1,1,1,4,4,4-hexafluorobutane comprises contacting E-1,1,1,4,4,4-hexafluorobut-2-ene with a chlorine source. A process for producing 1,1,1,4,4,4-hexafluoro-2-butyne comprises contacting 2,3-dichloro-1,1,1,4,4,4-hexafluorobutane with a base. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen and a catalyst.

Processes for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene and intermediates for producing same. A process for producing 2-chloro-1,1,1,4,4,4-hexafluorobutane comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the liquid phases. A process for producing E-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 2-chloro-1,1,1,4,4,4-hexafluorobutane with base. A process for producing 2,3-dichloro-1,1,1,4,4,4-hexafluorobutane comprises contacting E-1,1,1,4,4,4-hexafluorobut-2-ene with a chlorine source. A process for producing 1,1,1,4,4,4-hexafluoro-2-butyne comprises contacting 2,3-dichloro-1,1,1,4,4,4-hexafluorobutane with a base. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen and a catalyst.

A process for producing E-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with hydrogen fluoride in the vapor phase in the presence of a fluorination catalyst. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene further comprises contacting E-1,1,1,4,4,4-hexafluoro-2-butene with chlorine in the presence of a catalyst to produce 2,3-dichloro-1,1,1,4,4,4-hexafluorobutane, followed by reaction with base to produce 1,1,1,4,4,4-hexafluoro-2-butyne, and subsequently hydrogenating hexafluoro-2-butyne to produce Z-1,1,1,4,4,4-hexafluoro-2-butene.

A process for producing E-1,1,1,4,4,4-hexafluorobut-2-ene comprises contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with hydrogen fluoride in the vapor phase in the presence of a fluorination catalyst. A process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene further comprises contacting E-1,1,1,4,4,4-hexafluoro-2-butene with chlorine in the presence of a catalyst to produce 2,3-dichloro-1,1,1,4,4,4-hexafluorobutane, followed by reaction with base to produce 1,1,1,4,4,4-hexafluoro-2-butyne, and subsequently hydrogenating hexafluoro-2-butyne to produce Z-1,1,1,4,4,4-hexafluoro-2-butene.