Process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene and intermediates for producing same

Abstract

The process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene includes 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. The process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene further includes contacting the E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene with a base to produce 1,1,1,4,4,4-hexafluoro-2-butyne, and subsequently hydrogenating the hexafluoro-2-butyne to produce Z-1,1,1,4,4,4-hexafluoro-2-butene.

Description

[Technical field]

[0001] The disclosure herein relates to a process for producing Z-1,1,1,4,4,4-hexafluoro-2-butene, and to a process for producing intermediates useful in the production thereof. The disclosure further provides a process for producing E- and / or Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene. [Background technology]

[0002] Over the past several decades, many industries have been working to find alternatives to ozone-depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). CFCs and HCFCs have been used in a wide range of applications, including use as refrigerants, cleaning agents, blowing agents for thermoplastic and thermoset foams, heat transfer media, gaseous dielectrics, aerosol propellants, fire extinguishing and suppression agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasives, and displacement drying agents. In the search for alternatives to these versatile compounds, many industries have turned to the use of hydrofluorocarbons (HFCs). HFCs have zero ozone depletion potential and therefore will not be affected by the current regulatory phase-out as a result of the Montreal Protocol. Summary of the Invention [Problem to be solved by the invention]

[0003] In addition to the problem of ozone depletion, another environmental problem for many of these applications is global warming.Therefore, there is a need for compositions that meet low ozone depletion standards and have low global warming potential.It is believed that certain hydrofluoroolefins meet both of these goals.Therefore, there is a need for intermediates that are useful for producing hydrofluoroolefins, and for production processes that provide hydrofluoroolefins that do not contain chlorine and have low global warming potential.

[0004] Incorporation by Reference All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. In the case of conflict, the present application, including any definitions herein, will control. [Means for solving the problem]

[0005] The present disclosure provides processes for the production of hydrofluoroolefin Z-1,1,1,4,4,4-hexafluorobut-2-ene (Z-HFO-1336mzz, or Z-1336mzz), and processes for the production of intermediates useful in the production thereof.

[0006] The disclosure further provides a process for the production of a product mixture comprising E- and / or Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene (HCFO-1326mxz, 1326mxz), the process comprising contacting 1,1,2,4,4-pentachlorobuta-1,3-diene (HCC-2320az) with HF and a fluorination catalyst.

[0007] The present disclosure provides a process for the production of Z-1,1,1,4,4,4-hexafluorobut-2-ene, the process comprising: (a) contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the vapor phase in the presence of a chlorine source and a fluorination catalyst to produce a product mixture comprising E- and / or Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene; (b) contacting the E- and / or Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene with a base to produce a product mixture comprising 1,1,1,4,4,4-hexafluoro-2-butyne; and (c) contacting the 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen to produce a product mixture comprising Z-1,1,1,4,4,4-hexafluoro-2-butene.

[0008] In some embodiments, 1,1,2,4,4-pentachlorobuta-1,3-diene (HCC-2320az, 2320az) is produced according to a process that includes the dimerization of trichloroethylene (TCE). The process for producing 2320az includes contacting TCE in the presence of a catalyst to produce a product mixture that includes 2320az.

[0009] [ka]

[0010] In some embodiments, the dimerization of TCE is carried out using pentachloroethane (CCl) which facilitates the dimerization process. 3 CHCl 2 , HCC-120).

[0011] In certain embodiments, 2320az is produced with a selectivity of at least 80%. In some embodiments, the selectivity is greater than 90%, or greater than 95%, or greater than 99%, or greater than 99.5%. In certain embodiments, 2320az is recovered from the product mixture. In some embodiments, unreacted TCE is recovered and recycled.

[0012] The present disclosure further provides compositions produced according to the processes disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that includes a list of elements is not necessarily limited to those elements but may also include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0014] When an amount, concentration, or other value or parameter is given as either a range, a preferred range, or a list of upper and / or lower preferred values, these are to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, whether or not the ranges are separately disclosed. When a numerical range is described herein, unless otherwise indicated, the range is intended to include its endpoints, and to include all integers and fractions within the range.

[0015] By "recovering" is meant isolating the desired product sufficiently to make it available for its intended use, in the case of recovering Z-1,1,1,4,4,4-hexafluoro-2-butene useful as a starting material for a subsequent reaction step or, for example, as a refrigerant or foam expansion agent.

[0016] The details of the recovery step depend on the compatibility of the product mixture with the reaction conditions of the subsequent reaction step. For example, if the product is produced in a reaction medium that is different or incompatible with the subsequent reaction step, the recovery step may include separating the desired product from the product mixture including the reaction medium. This separation may be performed simultaneously with the contacting step when the desired product is volatile under the reaction conditions. Volatilization of the desired product may constitute isolation and thereby recovery of the desired product. If the vapor contains other materials intended to be separated from the desired product, the desired product may be separated, for example, by selective distillation.

[0017] The step of recovering the desired product from the product mixture preferably involves separating the desired product from the catalyst or other components of the product mixture used to produce the desired product or produced in the process.

[0018] The present disclosure provides, inter alia, processes for producing Z-1336mzz and processes for producing intermediates for producing Z-1336mzz. Such processes can use starting materials including 1,1,2,4,4-pentachlorobuta-1,3-diene, which can be produced from trichloroethylene by one of the methods described herein.

[0019] Formation of 1,1,2,4,4-pentachlorobuta-1,3-diene (2320az) 1,1,2,4,4-Pentachlorobuta-1,3-diene (HCC-2320az, or 2320az) may be produced according to the present disclosure by the dimerization of trichloroethylene (TCE). In some embodiments, a process is provided for producing a product mixture comprising 2320az, the process comprising contacting TCE with a dimerization catalyst at an elevated temperature.

[0020] In some embodiments, the dimerization catalyst comprises iron. The dimerization iron catalyst may comprise metallic iron from any source (including a combination of sources) and may be or include iron powder, iron wire, iron screen, or iron shavings. The iron catalyst may also be iron(III) chloride (FeCl 3 ) or iron(II) chloride (FeCl 2 ) may be included.

[0021] In some embodiments, the dimerization catalyst comprises copper. The dimerization copper catalyst may comprise metallic copper from any source (including a combination of sources), for example, may be or include copper powder or copper wire. The copper catalyst may also be copper(I) chloride (CuCl) or copper(II) chloride (CuCl 2 ) may be included.

[0022] The process is preferably carried out in an anhydrous environment, for example, if iron(III) chloride is used, the iron(III) chloride is preferably anhydrous.

[0023] In some embodiments, the dimerization catalyst has a specific concentration relative to the moles of TCE reactant used. Thus, in some embodiments where the catalyst comprises a metallic iron catalyst, the weight ratio of iron wire (or iron powder) catalyst to TCE is from about 0.0001 to about 1. In other embodiments, the weight ratio of iron catalyst to TCE is from about 0.01 to about 1.

[0024] In some embodiments, the dimerization catalyst comprises iron(III) chloride and the weight ratio of iron(III) chloride to TCE is from about 0.00001 to about 1. For example, the weight ratio of iron(III) chloride to TCE is from about 0.00001 to about 0.002, and in another example, the weight ratio is from about 0.00005 to about 0.001. In yet another example, the weight ratio of iron(III) chloride to TCE is from about 0.0001 to about 1, and in a further example, the weight ratio of iron(III) chloride to TCE is from about 0.00015 to about 1.

[0025] In some embodiments, trichloroethylene is contacted with a dimerization catalyst and pentachloroethane. The pentachloroethane (HCC-120) promotes a reaction to produce a product mixture that includes 2320az. In certain embodiments, the weight ratio of HCC-120 to TCE is about 0.001 to about 1. In other embodiments, the weight ratio of HCC-120 to TCE is about 0.005 to about 1.

[0026] The dimerization of TCE is carried out at an elevated temperature, for example, a temperature in the range of about 210 to about 235° C. The temperature may be greater than 200° C. The temperature may be less than 245° C.

[0027] The pressure is typically autogenous pressure.

[0028] The contact (residence) time is typically about 0.5 to 10 hours.

[0029] In some embodiments, the conversion of TCE is at least 15%, or at least 30%, or at least 50%. In some embodiments, the selectivity to 2320az is at least 80%, or at least 85%, or at least 90%.

[0030] By-products in the dimerization reaction may include tetrachloroethane isomers, tetrachlorobutadiene isomers, hexachlorobutene isomers, and trichloroethylene oligomers. The product mixture containing 2320az may further include E-1,1,2,3,4-pentachloro-1,3-butadiene or Z-1,1,2,3,4-pentachloro-1,3-butadiene. Thus, in one embodiment, there is a composition that includes 1,1,2,4,4-pentachlorobuta-1,3-diene, E-1,1,2,3,4-pentachlorobuta-1,3-diene, and Z-1,1,2,3,4-pentachlorobuta-1,3-diene.

[0031] The process may further include recovering 2320az from the product mixture prior to using the recovered 2320az as a starting material in processes to produce E- and Z-1326mxz, 1,1,1,4,4,4-hexafluoro-2-butyne, and HFO-Z-1336mzz, e.g., as described herein.

[0032] The process for recovering 2320az from the product mixture may include one or any combination of purification techniques known in the art, such as distillation. The process of "recovering" 2320az from the product mixture produces a product that contains at least 95%, or at least 97%, or at least 99% 2320az.

[0033] In certain embodiments, the process for producing 2320az may further include recovering trichloroethylene from the product mixture and recycling the recovered trichloroethylene to the dimerization process described herein.

[0034] In certain embodiments, the process for producing 2320az may further include recovering hexachlorobutene isomers from the product mixture and recycling the recovered hexachlorobutene isomers to the dimerization process described herein.

[0035] In certain embodiments, the process for producing 2320az may further include recovering pentachloroethane from the product mixture and recycling the recovered pentachloroethane to the dimerization process described herein.

[0036] If present, other products such as E-1,1,2,3,4-pentachloro-1,3-butadiene and Z-1,1,2,3,4-pentachloro-1,3-butadiene may also be recovered.

[0037] Formation of E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene (E / Z-1326mxz) Provided herein is a fluorination process comprising contacting 1,1,2,4,4-pentachlorobuta-1,3-diene (2320az) with HF in the presence of a fluorination catalyst comprising a metal halide and a chlorine source to provide a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene.

[0038] The fluorination catalyst comprises at least one metal halide, metal oxide, or metal oxyhalide. The reaction is carried out in the gas phase. The process produces a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene.

[0039] As used herein, the term "halide" refers to fluoride, chloride, and bromide.

[0040] Examples of suitable metals include nickel, chromium, iron, scandium, yttrium, lanthanum, titanium, zirconium, hafnium, vanadium, molybdenum, tungsten, manganese, rhenium, ruthenium, osmium, cobalt, palladium, copper, zinc, tantalum, antimony, aluminum, tin, and lead. Note that, for purposes of this definition, antimony is a metal.

[0041] Examples of metal halides include nickel halides, chromium halides, iron halides, scandium halides, yttrium halides, lanthanum halides, titanium halides, zirconium halides, hafnium halides, vanadium halides, molybdenum halides, tungsten halides, manganese halides, rhenium halides, ruthenium halides, osmium halides, cobalt halides, palladium halides, copper halides, zinc halides, antimony halides, tantalum halides, aluminum halides, tin halides, and lead halides. In some embodiments, the metal halide is a nickel halide, an iron halide, or a chromium halide, or a combination thereof, which is used as a catalyst supported on activated carbon or as a catalyst not supported on activated carbon. In other embodiments, the metal halide is a bromide or a chloride. In yet other embodiments, the halide is a chloride. In other embodiments, the metal halide is a nickel chloride, an iron chloride, or a chromium chloride, or a combination thereof.

[0042] Examples of metal oxides include chromium oxide and aluminum oxide. Metal oxyhalides may also be used as fluorination catalysts.

[0043] The fluorination catalyst may be unsupported or supported on activated carbon. The activated carbon may be unwashed or may be acid- or base-washed.

[0044] The term "activated carbon" refers to a carbon dioxide gas that has a molecular weight of about 50 to about 3000 m2 , or about 100 to about 2000 m 2 (For example, about 200 to about 1500 m 2 Or about 300 to about 1000 m 2 Activated carbon includes any carbon with a relatively high surface area, such as activated carbon (e.g., charcoal), nut shells (e.g., coconut), and wood. Any form of activated carbon can be used, including powdered, granular, and pelleted activated carbon.

[0045] In some embodiments, the activated carbon is washed with at least one basic solution to remove silicates. For example, the activated carbon is washed with an alkali or alkaline earth hydroxide or ammonium hydroxide. Examples of basic solutions that have been used to wash the activated carbon include sodium hydroxide, ammonium hydroxide, potassium hydroxide, etc.

[0046] The fluorination process is carried out in the presence of a chlorine source, which may be selected from: (i) a catalyst comprising a metal chloride or metal oxychloride, for example chromium chloride (CrCl), either as a metal chloride or as chromium chloride supported on carbon; 3 ), or (ii) chlorine (Cl 2 ), which is added to the process when the fluorination catalyst comprises a metal halide or metal oxyhalide, the halide being a fluoride or bromide when the catalyst is a metal oxide. Optionally, chlorine (Cl), when the catalyst is a metal chloride or metal oxychloride, 2 ) is added.

[0047] In one embodiment, the fluorination catalyst comprises a metal chloride or a metal oxychloride. In another embodiment, the fluorination catalyst does not comprise a metal chloride or a metal oxychloride, and the process does not involve chlorine (Cl 2 ) in the presence of chlorine (Cl 2 ) is present, chlorine (Cl 2The molar ratio of chlorine to 2320az (as) is typically about 0.5:1 to about 2:1. The preferred molar ratio of chlorine to 2320az is about 1.1:1 to about 1:1.

[0048] The molar ratio of HF to 2320az, HF:2320az, in some embodiments is from about 1:1 to about 35:1. In other embodiments, the molar ratio of HF to 2320az is from about 1:1 to about 25:1. HF may be added in an amount of 10 to 30 moles per mole of 2320az. In some embodiments, HF:2320az:Cl 2 The ratio is 10~30:1:1.

[0049] The process is carried out at an effective temperature and pressure. In one embodiment, the process is carried out in the vapor phase at a temperature ranging from about 250° C. to about 425° C. In another embodiment, the process is carried out at a temperature ranging from about 275° C. to about 400° C. In yet another embodiment, the process is carried out at a temperature ranging from about 300° C. to about 375° C., and in another embodiment, from about 325° C. to about 350° C.

[0050] In one embodiment, the process is carried out in the vapor phase at a pressure ranging from about 0 psig to about 200 psig, in another embodiment, the pressure ranges from about 30 psig to about 150 psig, and in another embodiment, the pressure ranges from about 40 psig to about 80 psig.

[0051] In one embodiment, the process is carried out at a temperature ranging from about 275 to about 375° C. and a pressure ranging from about 0 psig to about 160 psig, and in another embodiment, at a temperature ranging from about 300 to about 350° C. and a pressure ranging from about 0 psig to about 80 psig.

[0052] In a preferred embodiment, 2320az is vaporized, optionally in the presence of HF, to produce HF and Cl 2 is fed to the gas phase reactor together with

[0053] This process may further include a step of recovering E / Z-1326mxz from the product mixture before using the recovered E / Z-1326mxz as a starting material in the process for producing 1,1,1,4,4,4-hexafluoro-2-butyne. The process for recovering E / Z-1326mxz from the product mixture may include one or any combination of purification techniques known in the art, such as distillation. The step of "recovering" E / Z-1326mxz from the product mixture produces a product containing at least 95%, or at least 97%, or at least 99% of E / Z-1326mxz. There is no need to separate the E-isomer and the Z-1326mxz isomer.

[0054] The product mixture containing E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene may also contain E- and / or Z-1,1,1,4,4,4-hexafluoro-2-butene. If either E- or Z-1,1,1,4,4,4-hexafluoro-2-butene is present in the product mixture, each can be recovered for use as a product or reactant in another process.

[0055] Production of 1,1,1,4,4,4-Hexafluoro-2-butyne The present disclosure provides a process for dehydrochlorination of E- and Z-1326mxz at a temperature far below 100 °C using an aqueous basic solution combined with a quaternary alkylammonium salt as a phase transfer catalyst.

[0056] The present disclosure further provides a process comprising the step of contacting E- and / or Z-1326mxz with a base to produce a product mixture containing 1,1,1,4,4,4-hexafluoro-2-butyne (CF 3 C≡CCF 3 ) by a dehydrochlorination reaction. This base is preferably an aqueous basic medium. This reaction step is preferably carried out in the presence of a catalyst. Preferably, this aqueous basic medium includes an aqueous solution of an alkali metal hydroxide or an alkali metal halide salt or other bases. Preferably, this catalyst is a phase transfer catalyst.

[0057] As used herein, a phase transfer catalyst is intended to mean a substance that promotes the transfer of ionic compounds between an organic phase and an aqueous phase. In this process, the organic phase contains the E- and / or Z-1326mxz reactants and the aqueous phase contains the basic aqueous medium. The phase transfer catalyst promotes the reaction of these dissimilar and incompatible components.

[0058] Different phase transfer catalysts may function in different ways, but their mechanism of action does not limit their usefulness in the present invention, so long as the phase transfer catalyst promotes the dehydrochlorination reaction.

[0059] As used herein, the phase transfer catalyst is a quaternary alkyl ammonium salt, where the alkyl group is an alkyl chain having 4 to 12 carbon atoms. In one embodiment, the quaternary alkyl ammonium salt is a tetrabutyl ammonium salt. The anion of the salt can be a halide, such as chloride or bromide, hydrogen sulfate, or any other commonly used anion.

[0060] In some embodiments, at least one alkyl group of the quaternary alkyl ammonium salt contains at least 8 carbons. An example of a quaternary alkyl ammonium salt in which three alkyl groups contain at least 8 carbon atoms includes trioctylmethyl ammonium chloride. Aliquat® 336 is a commercially available phase transfer catalyst that contains trioctylmethyl ammonium chloride. An example of a quaternary alkyl ammonium salt in which four alkyl groups contain at least 8 carbon atoms includes tetraoctyl ammonium salt. The anion of such a salt may be a halide, such as chloride or bromide, hydrogen sulfate, or any other commonly used anion. Specific quaternary alkyl ammonium salts include tetraoctyl ammonium chloride, tetraoctyl ammonium hydrogen sulfate, tetraoctyl ammonium bromide, methyl trioctyl ammonium chloride, methyl trioctyl ammonium bromide, tetradecyl ammonium chloride, tetradecyl ammonium bromide, and tetradodecyl ammonium chloride.

[0061] Other compounds that are commonly considered to be phase transfer catalysts in other applications, such as crown ethers, cryptands, or nonionic surfactants alone, similarly do not significantly affect the conversion or rate of the dehydrochlorination reaction.

[0062] The Z- and E-isomers of 1,1,1,4,4,4-hexafluoro-2-chloro-2-butene exhibit significantly different reactivities with respect to dehydrochlorination and have different requirements for how to function as effective phase transfer catalysts in this reaction.

[0063] Dehydrochlorination of the Z-isomer of 1,1,1,4,4,4-hexafluoro-2-chloro-2-butene (Z-1326mxz) can be carried out using a quaternary alkylammonium salt, where the alkyl group is an alkyl chain having 4 to 12 carbon atoms. The anion of the salt can be a halide, such as chloride or bromide, hydrogen sulfate, or any other commonly used anion. In one embodiment, the quaternary alkylammonium salt is a tetrabutylammonium salt. In another embodiment, the quaternary alkylammonium salt is a tetrahexylammonium salt. In another embodiment, the quaternary alkylammonium salt is a tetraoctylammonium salt. In yet another embodiment, the quaternary alkylammonium salt is a trioctylmethylammonium salt.

[0064] The dehydrochlorination of the E-isomer of 1,1,1,4,4,4-hexafluoro-2-chloro-2-butene (E-1326mxz) can be carried out using a quaternary alkyl ammonium salt, in which the alkyl group is an alkyl chain with at least one alkyl chain having 8 or more carbons. In another embodiment, the quaternary alkyl ammonium salt has three alkyl chains having 8 or more carbons, such as trioctylmethyl ammonium salt. In yet another embodiment, the quaternary alkyl ammonium salt is a tetraoctyl ammonium salt. In yet another embodiment, the quaternary alkyl ammonium salt is a tetradecyl ammonium salt. In yet another embodiment, the quaternary alkyl ammonium salt is a tetradodecyl ammonium salt. The anion of the salt can be a halide, such as chloride or bromide, hydrogen sulfate, or any other commonly used anion.

[0065] In yet another embodiment, the dehydrochlorination of E-1326mxz can be carried out in the presence of a non-ionic surfactant using a quaternary alkyl ammonium salt, where the alkyl group is an alkyl chain having 4 to 12 carbon atoms. The non-ionic surfactant can be an ethoxylated nonylphenol, and an ethoxylated C12-C15 straight chain aliphatic alcohol. Suitable non-ionic surfactants include Bio-soft® N25-9 and Makon® 10, available from Stepan Company.

[0066] In one embodiment, the quaternary alkyl ammonium salt is added in an amount between 0.5 mole percent and 2 mole percent of 1326mxz. In another embodiment, the quaternary alkyl ammonium salt is added in an amount between 1 mole percent and 2 mole percent of 1326mxz. In yet another embodiment, the quaternary alkyl ammonium salt is added in an amount between 1 mole percent and 1.5 mole percent of 1326mxz.

[0067] In one embodiment, the dehydrochlorination of Z- or E-1326mxz is carried out in the presence of an alkali metal halide salt. In one embodiment, the alkali metal is sodium or potassium. In one embodiment, the halide is chloride or bromide. In one embodiment, the alkali metal halide salt is sodium chloride. Without being bound to any particular theory, it is believed that the alkali metal halide salt stabilizes the phase transfer catalyst. Although the dehydrochlorination reaction itself produces an alkali metal chloride, particularly sodium chloride when sodium hydroxide is used as the base, the addition of sodium chloride has the added benefit of increasing the yield of hexafluoro-2-butyne.

[0068] The addition of alkali metal halide salts also reduces the amount of fluoride ion measured in the effluent water from the reaction. Without being bound to any particular theory, it is believed that the presence of fluoride results from decomposition of either the 1326mxz starting material or the 1,1,1,4,4,4-hexafluoro-2-butyne product.

[0069] In some samples, the amount of fluoride ion found in the effluent from the dehydrochlorination is about 6000 ppm. In some examples, using 30-60 equivalents of sodium chloride per mole of phase transfer catalyst reduces the amount of fluoride ion in the effluent to 2000 ppm. In one embodiment, the alkali metal halide is added at 25-100 equivalents per mole of phase transfer catalyst. In another embodiment, the alkali metal halide is added at 30-75 equivalents per mole of phase transfer catalyst. In yet another embodiment, the alkali metal halide is added at 40-60 equivalents per mole of phase transfer catalyst.

[0070] In one embodiment, the reaction is carried out at a temperature of about 60-90° C. In another embodiment, the reaction is carried out at 70° C.

[0071] As used herein, a basic aqueous solution is a liquid (either a solution, dispersion, emulsion, or suspension, etc.) that is primarily an aqueous liquid with a pH greater than 7. In some embodiments, the basic aqueous solution has a pH greater than 8. In some embodiments, the basic aqueous solution has a pH greater than 10. In some embodiments, the basic aqueous solution has a pH between 10 and 13. In some embodiments, the basic aqueous solution contains a small amount of an organic liquid that may be miscible or immiscible with water. In some embodiments, the liquid medium in the basic aqueous solution is at least 90% water. In one embodiment, the water is tap water, and in other embodiments, the water is deionized or distilled water.

[0072] The base in the basic aqueous solution is selected from the group consisting of hydroxides, oxides, carbonates, or phosphates of alkali, alkaline earth metals, and mixtures thereof. In one embodiment, bases that can be used are lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium oxide, calcium oxide, sodium carbonate, potassium carbonate, trisodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, and mixtures thereof.

[0073] The product 1,1,1,4,4,4-hexafluoro-2-butyne (boiling point -25°C) can be recovered from the product mixture by distillation, where the butyne is evaporated from the aqueous medium and then condensed. Unconverted E- and / or Z-1326mxz can be recovered from the organic phase of the product mixture and recycled to the dehydrochlorination process.

[0074] Preparation of Z-1,1,1,4,4,4-hexafluoro-2-butene The present disclosure further provides a hydrogenation process comprising contacting 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen to produce a product mixture comprising Z-1,1,1,4,4,4-hexafluoro-2-butene (Z-1336mzz), preferably carried out in the presence of an alkine-to-alkene catalyst.

[0075] In some embodiments, the hydrogenation of 1,1,1,4,4,4-hexafluoro-2-butyne is carried out as a batch process in the liquid phase.

[0076] In some embodiments, the hydrogenation of 1,1,1,4,4,4-hexafluoro-2-butyne is carried out as a continuous process in the gas phase.

[0077] In some embodiments, the alkyne-to-alkene catalyst is a palladium catalyst, such as palladium dispersed on aluminum oxide or titanium silicate doped with silver and / or lanthanides. The loading of palladium dispersed on aluminum oxide or titanium silicate is relatively low. In some embodiments, the palladium loading is from about 100 ppm to about 5000 ppm. In other embodiments, the palladium loading is from about 200 ppm to about 5000 ppm. In some embodiments, the palladium catalyst is doped with at least one of silver, cerium, or lanthanum. In some embodiments, the molar ratio of cerium or lanthanum to palladium is from about 2:1 to about 3:1. In some embodiments, the molar ratio of silver to palladium is about 0.5:1.0.

[0078] Another embodiment of the alkyne-to-alkene catalyst is Lindlar's catalyst. It is a heterogeneous palladium catalyst supported on a calcium carbonate support and deactivated or conditioned with a lead compound. The lead compound can be lead acetate, lead oxide, or any other suitable lead compound. In some embodiments, the catalyst is produced by reducing a palladium salt in the presence of a slurry of calcium carbonate and then adding a lead compound. In some embodiments, the palladium salt is palladium chloride.

[0079] In other embodiments, the Lindlar catalyst is further deactivated or conditioned with quinoline. The amount of palladium on the support is typically about 5% by weight, but may be any catalytically effective amount. In other embodiments, the amount of palladium supported on the support in the Lindlar catalyst is greater than 5% by weight. In yet other embodiments, the amount of palladium supported on the support may be from about 5% by weight to about 1% by weight.

[0080] In some embodiments, the amount of catalyst used is from about 0.5% to about 4% by weight of the amount of 1,1,1,4,4,4-hexafluoro-2-butyne. In other embodiments, the amount of catalyst used is from about 1% to about 3% by weight of the amount of the butyne. In yet other embodiments, the amount of catalyst used is from about 1% to about 2% by weight of the amount of the butyne.

[0081] In some embodiments, the reaction step is a batch reaction and is carried out in the presence of a solvent. In one such embodiment, the solvent is an alcohol. Exemplary alcohol solvents include ethanol, i-propanol, and n-propanol. In other embodiments, the solvent is a fluorocarbon or hydrofluorocarbon. Exemplary fluorocarbons or hydrofluorocarbons include 1,1,1,2,2,3,4,5,5,5-decafluoropentane and 1,1,2,2,3,3,4-heptafluorocyclopentane.

[0082] In some embodiments, the reaction of 1,1,1,4,4,4-hexafluoro-2-butyne with hydrogen is preferably carried out by adding hydrogen in small increments, with each addition increasing the pressure in the vessel by no more than about 100 psi (0.69 MPa). In other embodiments, the addition of hydrogen is controlled to increase the pressure in the vessel by no more than about 50 psi (0.35 MPa) with each addition. In some embodiments, hydrogen can be added in larger increments to the residue of the reaction after enough hydrogen has been consumed in the hydrogenation reaction to convert at least 50% of the butyne to Z-1336mzz. In other embodiments, hydrogen can be added in larger increments to the residue of the reaction after enough hydrogen has been consumed in the hydrogenation reaction to convert at least 60% of the butyne to the desired butene. In yet other embodiments, hydrogen can be added in larger increments to the residue of the reaction after enough hydrogen has been consumed in the hydrogenation reaction to convert at least 70% of the butyne to the desired butene. In some embodiments, the larger increment of hydrogen loading may be 300 psi (2.07 MPa). In other embodiments, the larger increment of hydrogen loading may be 400 psi (2.76 MPa).

[0083] In some embodiments, the molar ratio is about 1 mole of hydrogen to about 1 mole of 1,1,1,4,4,4-hexafluoro-2-butyne. In other embodiments, the molar ratio is about 0.9 moles to about 1.3 moles of hydrogen to butyne. In yet other embodiments, the amount of hydrogen added is from about 0.95 moles of hydrogen to about 1.1 moles of butyne. In yet other embodiments, the amount of hydrogen added is from about 0.95 moles of hydrogen to about 1.03 moles of butyne.

[0084] In some embodiments, the hydrogenation is carried out at ambient temperature (15° C. to 25° C.). In other embodiments, the hydrogenation is carried out at a temperature higher than ambient temperature. In yet other embodiments, the hydrogenation is carried out at a temperature lower than ambient temperature. In yet other embodiments, the hydrogenation is carried out at a temperature less than about 0° C.

[0085] In an embodiment of a continuous process, a mixture of 1,1,1,4,4,4-hexafluoro-2-butyne and hydrogen is passed through a reaction zone containing a catalyst. A reaction vessel (e.g., a metal tube) may be used to pack the catalyst to form the reaction zone. In some embodiments, the molar ratio of hydrogen to butyne is about 1:1. In other embodiments of a continuous process, the molar ratio of hydrogen to butyne is less than 1:1. In yet other embodiments, the molar ratio of hydrogen to butyne is about 0.67:1.0.

[0086] In some embodiments of a continuous process, the reaction zone is maintained at ambient temperature. In other embodiments of a continuous process, the reaction zone is maintained at a temperature of 30° C. In yet other embodiments of a continuous process, the reaction zone is maintained at a temperature of about 40° C.

[0087] In some embodiments of the continuous process, the flow rates of 1,1,1,4,4,4-hexafluoro-2-butyne and hydrogen are maintained to provide a residence time in the reaction zone of about 30 seconds. In other embodiments of the continuous process, the flow rates of butyne and hydrogen are maintained to provide a residence time in the reaction zone of about 15 seconds. In yet other embodiments of the continuous process, the flow rates of butyne and hydrogen are maintained to provide a residence time in the reaction zone of about 7 seconds.

[0088] It is understood that the residence time in the reaction zone can be reduced by increasing the flow rate at which 1,1,1,4,4,4-hexafluoro-2-butyne and hydrogen enter the reaction zone. As the flow rate increases, the amount of butyne hydrogenated per unit time increases. Since hydrogenation is exothermic, at higher flow rates, depending on the length and diameter of the reaction zone and its heat dissipation capacity, it may be desirable to provide an external cooling source to the reaction zone to maintain the desired temperature.

[0089] The contacting step conditions, including the selection of the catalyst, are preferably selected to produce Z-1336mzz with a selectivity of at least 85%, more preferably at least 90%, and most preferably at least 95%.

[0090] In some embodiments, upon completion of the batch or continuous hydrogenation process, Z-1336mzz can be recovered by any conventional process, including, for example, fractional distillation. Unconverted hexafluoro-2-butyne may be recovered and recycled to the hydrogenation process. In other embodiments, upon completion of the batch or continuous hydrogenation process, Z-1336mzz has sufficient purity such that no further purification steps are required. EXAMPLES

[0091] material Trichloroethylene, iron(III) chloride, chromium chloride, alumina chloride, copper(II) chloride, chlorine, pentachloroethane (HCC-120), trioctylmethylammonium chloride (Aliquat® 336), NaOH, K 2 HPO 4 and K.H. 2 PO 4 , and Lindlar catalyst are available from Sigma Aldrich (St. Louis, MO). Hydrogen fluoride and E-1,1,1,4,4,4-hexafluoro-2-butene are available from Synquest Labs, Inc. (Alachua, FL). 10% chromium chloride on carbon catalyst is available from BASF (Iselin, NJ).

[0092] GC analyses of Examples 1-4 were carried out using an Agilent® 5975GC, RESTEK Rtx-1 column.

[0093] Example 1: Preparation of 1,1,2,4,4-pentachlorobuta-1,3-diene (HCC-2320az) Trichloroethylene (100 g, 0.76 mol) was dissolved in 30 mg of anhydrous FeCl 3 The reaction mixture was heated at 230° C. for 2 hours. The reactor contents were cooled to room temperature and analyzed by GC to determine conversion and selectivity. The results are shown in Table 1.

[0094] Example 2: Preparation of 1,1,2,4,4-pentachlorobuta-1,3-diene (HCC-2320az) Trichloroethylene (100 g, 0.76 moles) was added to a shaker tube containing 1 g of iron wire. The reaction mixture was heated at 230° C. for 2 hours. The reactor contents were cooled to room temperature and analyzed by GC to determine the conversion and selectivity. The results are shown in Table 1.

[0095] Example 3: Preparation of 1,1,2,4,4-pentachlorobuta-1,3-diene (HCC-2320az) Trichloroethylene (100 g, 0.76 mol) was dissolved in 20 mg of anhydrous FeCl 3 and 1 g of HCC-120 were added to a shaker tube. The reaction mixture was heated at 230° C. for 2 hours. The reactor contents were cooled to room temperature and analyzed by GC to determine the conversion and selectivity. The results are shown in Table 1.

[0096] Example 4: Preparation of 1,1,2,4,4-pentachlorobuta-1,3-diene (HCC-2320az) Trichloroethylene (100 g, 0.76 moles) was added to a shaker tube containing 1 g of iron wire and 1 g of HCC-120. The reaction mixture was heated at 230° C. for 2 hours. The reactor contents were cooled to room temperature and analyzed by GC to determine the conversion and selectivity. The results are shown in Table 1.

[0097] [Table 1]

[0098] As can be seen from Table 1, FeCl 3 Or when using an Fe wire catalyst, the presence of HCC-120 increases the conversion of trichloroethylene to 2320az.

[0099] Example 5: Preparation of E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene An Inconel tube (0.5 inch OD, 15 inch long, 0.34 inch wall thickness) was packed with 12 cc (6.45 g) of 10% chromium chloride on carbon catalyst. The reactor was heated to 250°C in a Lindberg furnace and 0.09 mL / hr of 2320az and 5.4 sccm (standard cubic centimeters per minute) of HF gas were fed through a vaporizer controlled at 200°C. Over the course of the run, the temperature was increased to 325°C. All experiments were carried out at 1-2 psig. The reactor effluent was analyzed on-line. This was performed using an Agilent® 6890 GC / 5973 MS and a Restek® PC2618 5% Krytox® CBK-D / 60 / 80, 6 meter x 2 mm ID 1 / 8" OD packed column, purged with 30 sccm helium. The run conditions are shown in Table 2. The data are shown in Table 3. Samples are taken at hourly intervals.

[0100] [Table 2]

[0101] [Table 3]

[0102] Example 6: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of Z-1326 (20 g, 0.1 mol) and water (18 mL) in the presence of tetra-n-butylammonium bromide (0.45 g, 0.001325 mol) at 35° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 1 h, and 15.4 g of product (conversion: 100%, yield: 95%) was collected in a dry ice trap. The results are shown in Table 4.

[0103] Example 7: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of Z-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tetra-n-butylammonium hydrogen sulfate (0.43 g, 0.001325 mol) at 35° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 1 h, and 11 products (conversion: 100%, yield: 71%) were collected in a dry ice trap. The results are shown in Table 4.

[0104] Example 8: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of Z-1326 (20 g, 0.1 mol) and water (18 mL) in the presence of Aliquat® 336 (0.53 g, 0.001325 mol) at 35° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 1 h and 15.6 g of product (conversion: 100%, yield: 96%) was collected in a dry ice trap. The results are shown in Table 4.

[0105] Example 9: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326 (20 g, 0.1 mol) and water (18 mL) in the presence of Aliquat® 336 (0.53 g, 0.001325 mol) at 42° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 1 h and 15.8 g of product (conversion: 100%, yield: 98%) was collected in a dry ice trap. The results are shown in Table 4.

[0106] Example 10: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tetra-n-butylammonium bromide (0.45 g, 0.001325 mol) at 42° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was not complete after 7 hours. 12.6 g of product (conversion: 78%, yield: 78%) was collected in a dry ice trap. The results are shown in Table 4.

[0107] Example 11: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tetra-n-butylammonium hydrogen sulfate (0.43 g, 0.001325 mol) at 42° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was not complete after 7 hours. 12.6 g of product (conversion: 77%, yield: 77%) was collected in a dry ice trap. The results are shown in Table 4.

[0108] Example 12: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tetraoctylammonium bromide (0.72 g, 0.001325 mol) at 42° C. After addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was completed after 6.5 h. 15.6 g of product (conversion: 100%, yield: 95%) was collected in a dry ice trap. The results are shown in Table 4.

[0109] Example 13: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tetraoctylammonium chloride (0.43 g, 0.001325 mol) at 42° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. After 5.5 hours, 15.2 g of product (conversion: 95%, yield: 93%) was collected in a dry ice trap. The results are shown in Table 4.

[0110] Example 14: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tetra-n-butylammonium chloride (0.37 g, 0.001325 mol) at 42° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. After 23 h, 14.8 g of product (conversion: 90%, yield: 87%) was collected in a dry ice trap. The results are shown in Table 4.

[0111] Example 15: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of E-1326mxz (20 g, 0.1 mol) and water (18 mL) in the presence of tributylmethylammonium chloride (0.31 g, 0.001325 mol) at 42° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. After 23 h, 8 g of product (conversion: 59%, yield: 49%) was collected in a dry ice trap. The results are shown in Table 4.

[0112] Example 16: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20 g, 0.1 mol) and water (18 mL) in the presence of tetrabutylammonium bromide (0.45 g, 0.001325 mol) and Bio-soft® N25-9 (0.7 g) at 38° C. After addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was completed after 5 h. 13 g of product (conversion: 100%, yield: 80%) was collected in a dry ice trap. The results are shown in Table 4.

[0113] Example 17: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH (12 mL, 0.12 mol) was added to a mixture of ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20 g, 0.1 mol) and water (18 mL) in the presence of tetrabutylammonium bromide (0.45 g, 0.001325 mol) and Makon® 10 (0.7 g) at 38° C. After addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 5 h. 11.2 g of product (conversion: 100%, yield 69%) was collected in a dry ice trap. The results are shown in Table 4.

[0114] Example 18: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne 10M NaOH aqueous solution (12mL, 0.12mol) was added to ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20g, 0.1mol) and water (18mL) in the presence of NaCl (2.3g, 0.0393mol) and Aliquat® 336 (0.53g, 0.001325mol) at 37°C over 30 minutes. After the addition was complete, the reaction temperature was raised to 70°C and the reaction was monitored using gas chromatography. The reaction was complete after 1 hour and 20 minutes and the aqueous layer was used for fluoride wt% analysis. The results are shown in Table 4.

[0115] Example 19: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH (12 mL, 0.12 mol) was added to ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20 g, 0.1 mol) and water (18 mL) in the presence of NaCl (4.6 g, 0.0786 mol) and Aliquat® 336 (0.53 g, 0.001325 mol) at 37° C. over 30 min. After addition was complete, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 1 h 20 min and the aqueous layer was used for fluoride wt % analysis. The results are shown in Table 4.

[0116] Example 20: Preparation of 1,1,1,4,4,4-hexafluoro-2-butyne Aqueous NaOH (12 mL, 0.12 mol) was added over 30 min to a mixture of ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20 g, 0.1 mol) and water (18 mL) in the presence of NaCl (3.45 g, 0.0590 mol) and Aliquat® 336 (0.53 g, 0.001325 mol) at 37° C. After addition was complete, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was complete after 2 h and the aqueous layer was used for fluoride wt % analysis. The results are shown in Table 4.

[0117] Comparative example A Aqueous NaOH solution (12 mL, 0.12 mol) was added to a mixture of ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20 g, 0.1 mol) and water (18 mL) at 37° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. After 31 h, 0.36 g of product (conversion: 2.2%, yield: 2.2%) was collected in a dry ice trap. The results are shown in Table 4.

[0118] Comparative example B Aqueous NaOH solution (6 mL, 0.06 mol) was added to a mixture of ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (10 g, 0.05 mol) and water (18 mL) in the presence of 15-crown-5 (0.65 g, 0.003 mol) at 37° C. After the addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was not complete after 30 h. 1.16 g of product (conversion: 14%, yield: 14%) was collected in a dry ice trap. The results are shown in Table 4.

[0119] Comparative example C Aqueous NaOH (12 mL, 0.12 mol) was added to a mixture of ZE-1326mxz (mixture of 50% Z-1326mxz and 50% E-1326mxz) (20 g, 0.1 mol) and water (18 mL) in the presence of Makon® 10 (0.7 g) at 37° C. After addition, the reaction temperature was raised to 70° C. and the reaction was monitored using gas chromatography. The reaction was not complete after 22 h. 1.09 g of product (conversion: 17%, yield: 6.8%) was collected in a dry ice trap. The results are shown in Table 4.

[0120] [Table 4] Note: Time is in hours and conversion refers to weight % conversion of 1326. Yield is weight % yield of 1,1,1,4,4,4-hexafluoro-2-butyne produced.

[0121] Example 21: Preparation of Z-1,1,1,4,4,4-hexafluoro-2-butene 1,1,1,4,4,4-Hexafluoro-2-butyne produced according to Example 9 was reacted with hydrogen to produce the desired Z isomer of 1,1,1,4,4,4-hexafluoro-2-butene by the following procedure: 5 g of Lindlar catalyst (lead-poisoned CaCO 3A 1.3 L rocker bomb was charged with 480 g (2.96 mol) of hexafluoro-2-butyne. The reactor was cooled (-78°C) and vented. After warming the bomb to room temperature, H was added in increments not exceeding Δp = 50 psi (0.35 MPa). 2 A total of 3 moles of H was slowly added. 2 was added to the reactor. Gas chromatographic analysis of the crude product showed that the mixture was 3 C≡CCF 3 (0.236%), trans-isomer E-CF 3 CH=CHCF 3 (0.444%), saturated CF 3 CH 2 CH 2 CF 3 (1.9%), CF 2 = CHCl (impurity from starting material butyne) (0.628%), cis-isomer Z-CF 3 CH=CHCF 3 It was shown that the total number of sigma-doped ...

[0122] Distillation of the crude product afforded 287 g (59% yield) of 100% pure cis-CF 3 CH=CHCF 3 (boiling point 33.3°C). MS: 164 [MI], 145 [M-19], 95 [CF3CH=CH], 69 [CF3]. NMR 1 H: 6.12 ppm (multiplet), 19 F: -60.9 ppm (triplet J = 0.86 Hz). The selectivity of this reaction towards the formation of the Z-isomer was 96.98%. The Z-isomer was recovered by distillation.

[0123] Other embodiments 1. In some embodiments, the disclosure provides a fluorination process for producing a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene, the process comprising contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the vapor phase in the presence of a chlorine source and a fluorination catalyst comprising a metal halide to produce a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene.

[0124] 2. In some embodiments, the fluorination catalyst comprises a metal chloride.

[0125] 3. In some embodiments, the fluorination catalyst does not contain metal chlorides and the process does not involve chlorine (Cl 2 ) is carried out.

[0126] 4. In some embodiments, the fluorination catalyst comprises a metal chloride selected from nickel chloride, iron chloride, or chromium chloride, or a combination thereof.

[0127] 5. In some embodiments, the fluorination catalyst is unsupported.

[0128] 6. In some embodiments, the fluorination catalyst is supported on activated carbon.

[0129] 7. In some embodiments, chlorine (Cl) to 1,1,2,4,4-pentachlorobuta-1,3-diene 2 The ratio of (as) is 0.5:1 to 2:1.

[0130] 8. In some embodiments, the molar ratio of HF to 1,1,2,4,4-pentachlorobuta-1,3-diene, HF:2320az, is from about 1:1 to about 35:1.

[0131] 9. In some embodiments, the fluorination process is carried out at a temperature in the range of 250 to 425°C.

[0132] 10. In some embodiments, the fluorination process is carried out at a pressure ranging from 0 to 200 psi (0 to 1.4 MPa).

[0133] 11. In some embodiments, the process of any one of embodiments 1-10 further comprises producing 1,1,2,4,4-pentachlorobuta-1,3-diene by contacting trichloroethylene with a dimerization catalyst comprising iron to produce a product mixture comprising 1,1,2,4,4-pentachlorobuta-1,3-diene.

[0134] 12. In some embodiments, in the process of any embodiment 11, trichloroethylene is contacted with a dimerization catalyst comprising iron and pentachloroethane.

[0135] 13. In some embodiments, the present disclosure provides a process for producing a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene, the process comprising: (a) producing 1,1,2,4,4-pentachlorobuta-1,3-diene by contacting trichloroethylene with a dimerization catalyst to produce a product mixture comprising 1,1,2,4,4-pentachlorobuta-1,3-diene; (b) contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the vapor phase in the presence of a chlorine source, and a fluorination catalyst comprising a metal halide, to produce a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2butenes.

[0136] 14. In some embodiments, the present disclosure provides a process for producing a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene, the process comprising: (a) producing 1,1,2,4,4-pentachlorobuta-1,3-diene by contacting trichloroethylene with a dimerization catalyst and pentachloroethane to produce a product mixture comprising 1,1,2,4,4-pentachlorobuta-1,3-diene; (b) contacting 1,1,2,4,4-pentachlorobuta-1,3-diene with HF in the vapor phase in the presence of a chlorine source, and a fluorination catalyst comprising a metal halide, to produce a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2butenes.

[0137] 15. In some embodiments, the process of embodiment 13 or 14 further comprises recovering 1,1,2,4,4-pentachlorobuta-1,3-diene from the product mixture of step (a).

[0138] 16. In some embodiments, the process of embodiment 13 or 14 or 15 further comprises recovering trichloroethylene from the product mixture of step (a).

[0139] 17. In some embodiments, the present disclosure provides a process for producing Z-1,1,1,4,4,4-hexafluorobut-2-ene, the process comprising: (a) contacting trichloroethylene with a dimerization catalyst to produce a product mixture comprising 1,1,2,4,4-pentachlorobuta-1,3-diene; (b) contacting 1,1,2,4,4-pentachlorobuta-1,3-diene in the vapor phase with HF in the presence of a chlorine source and a fluorination catalyst comprising a metal halide to produce a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2butenes; (c) contacting the E- and / or Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene with a base to produce a product mixture comprising 1,1,1,4,4,4-hexafluoro-2-butyne; (d) 1,1,1,4,4,4-Hexafluoro-2-butyne with H 2to produce a product mixture comprising Z-1,1,1,4,4,4-hexafluorobut-2-ene.

[0140] 18. In some embodiments, the process of embodiment 17 further comprises recovering 1,1,2,4,4-pentachlorobuta-1,3-diene from the product mixture of step (a).

[0141] 19. In some embodiments, the process of embodiment 17 or 19 further comprises recovering trichloroethylene from the product mixture of step (a).

[0142] 20. In some embodiments, embodiments 17, 18, and 19 further comprise recovering E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butene from the product mixture of step (b).

[0143] 21. In some embodiments, embodiments 17, 18, 19, and 20 further comprise recovering 1,1,1,4,4,4-hexafluoro-2-butyne from the product mixture of step (c).

[0144] 22. In some embodiments, embodiments 17, 18, 19, 20, and 21 further comprise recovering Z-1,1,1,4,4,4-hexafluoro-2-butene from the product mixture of step (d).

[0145] Although the present invention has been described in conjunction with its detailed description, it should be understood that the foregoing description is intended to illustrate, but not to limit, the scope of the invention as defined by the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims. It should be understood by those skilled in the art that the present invention can be combined with any of the features described herein with respect to any particular aspect and / or embodiment of the invention with any of the other features of any other aspect and / or embodiment of the invention described herein, with appropriate modifications to ensure compatibility of the combination. Such combinations are considered to be part of the invention contemplated by this disclosure.

Claims

1. 1. A process for producing a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butenes, the process comprising the steps of contacting 1,1,2,4,4-pentachlorobuta-1,3-diene in the vapor phase with HF in the presence of a chlorine source and a fluorination catalyst to produce a product mixture comprising E- and Z-1,1,1,4,4,4-hexafluoro-2-chloro-2-butenes; The process wherein the fluorination catalyst comprises chromium chloride, and the catalyst is the chlorine source.

2. 2. The process of claim 1, wherein the molar ratio of HF to 1,1,2,4,4-pentachlorobuta-1,3-diene is from 1 to 35.

3. 2. The process of claim 1, further comprising the step of producing 1,1,2,4,4-pentachlorobuta-1,3-diene by contacting trichloroethylene with a dimerization catalyst comprising iron and pentachloroethane to produce a product mixture comprising 1,1,2,4,4-pentachlorobuta-1,3-diene.

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