Provided is a method for producing hexafluoro-1,3-butadiene, and the method can produce hexafluoro-1,3-butadiene at an industrially sufficient level of yield. In a reaction liquid containing a halogenated butane represented by chemical formula, CF.sub.2X.sup.1—CFX.sup.2—CFX.sup.3—CF.sub.2X.sup.4 (X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are each independently a halogen atom other than a fluorine atom), zinc, and an organic solvent, a reaction is conducted to eliminate the halogen atoms other than a fluorine atom, X.sup.1, X.sup.2, X.sup.3, and X.sup.4, from the halogenated butane, yielding hexafluoro-1,3-butadiene. During the reaction, the concentration of a zinc halide generated by the reaction, in the reaction liquid is not more than the solubility of the zinc halide in the organic solvent.

Provided is a method for producing hexafluoro-1,3-butadiene, and the method can produce hexafluoro-1,3-butadiene at an industrially sufficient level of yield. In a reaction liquid containing a halogenated butane represented by chemical formula, CF.sub.2X.sup.1—CFX.sup.2—CFX.sup.3—CF.sub.2X.sup.4 (X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are each independently a halogen atom other than a fluorine atom), zinc, and an organic solvent, a reaction is conducted to eliminate the halogen atoms other than a fluorine atom, X.sup.1, X.sup.2, X.sup.3, and X.sup.4, from the halogenated butane, yielding hexafluoro-1,3-butadiene. During the reaction, the concentration of a zinc halide generated by the reaction, in the reaction liquid is not more than the solubility of the zinc halide in the organic solvent.

Provided is a method for producing hexafluoro-1,3-butadiene, and the method can produce hexafluoro-1,3-butadiene at an industrially sufficient level of yield. In a reaction liquid containing a halogenated butane represented by chemical formula, CF.sub.2X.sup.1—CFX.sup.2—CFX.sup.3—CF.sub.2X.sup.4 (X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are each independently a halogen atom other than a fluorine atom), zinc, and an organic solvent, a reaction is conducted to eliminate the halogen atoms other than a fluorine atom, X.sup.1, X.sup.2, X.sup.3, and X.sup.4, from the halogenated butane, yielding hexafluoro-1,3-butadiene. During the reaction, the concentration of a zinc halide generated by the reaction, in the reaction liquid is not more than the solubility of the zinc halide in the organic solvent.

Provided is a method that is for producing hexafluoro-1,3-butadiene, discharges small amounts of industrial wastes, and is industrially applicable. The method for producing hexafluoro-1,3-butadiene includes a reaction step of reacting a halogenated butane represented by chemical formula, CF.sub.2X.sup.1-CFX.sup.2-CFX.sup.3-CF.sub.2X.sup.4 (X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are each independently a halogen atom other than a fluorine atom) in an organic solvent in the presence of zinc to eliminate the halogen atoms, X.sup.1, X.sup.2, X.sup.3, and X.sup.4, other than the fluorine atoms to generate hexafluoro-1,3-butadiene, giving a reaction product containing the hexafluoro-1,3-butadiene, and an aftertreatment step of separating the hexafluoro-1,3-butadiene from the reaction product produced in the reaction step, then adding water to a reaction product residue after the separating, and removing the organic solvent, giving an aqueous solution of zinc halide.

Provided is a method that is for producing hexafluoro-1,3-butadiene, discharges small amounts of industrial wastes, and is industrially applicable. The method for producing hexafluoro-1,3-butadiene includes a reaction step of reacting a halogenated butane represented by chemical formula, CF.sub.2X.sup.1-CFX.sup.2-CFX.sup.3-CF.sub.2X.sup.4 (X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are each independently a halogen atom other than a fluorine atom) in an organic solvent in the presence of zinc to eliminate the halogen atoms, X.sup.1, X.sup.2, X.sup.3, and X.sup.4, other than the fluorine atoms to generate hexafluoro-1,3-butadiene, giving a reaction product containing the hexafluoro-1,3-butadiene, and an aftertreatment step of separating the hexafluoro-1,3-butadiene from the reaction product produced in the reaction step, then adding water to a reaction product residue after the separating, and removing the organic solvent, giving an aqueous solution of zinc halide.

According to a method for producing a perfluoroalkadiene compound represented by general formula (1): CF.sub.2═CF—(CF.sub.2).sub.n-4—CF═CF.sub.2 (1), wherein n is an integer of 4 or more, the method comprising a reaction step of adding a nitrogen-containing compound to a solution of a compound represented by general formula (2): X.sup.1CF.sub.2—CFX.sup.2—(CF.sub.2).sub.n-4—CF.sub.2X.sup.1 (2), wherein n is the same as above, X.sup.1 is the same or different and is a halogen atom other than fluorine, and X.sup.2 is a halogen atom, the perfluoroalkadiene compound can be obtained at a high yield.

According to a method for producing a perfluoroalkadiene compound represented by general formula (1): CF.sub.2═CF—(CF.sub.2).sub.n-4—CF═CF.sub.2 (1), wherein n is an integer of 4 or more, the method comprising a reaction step of adding a nitrogen-containing compound to a solution of a compound represented by general formula (2): X.sup.1CF.sub.2—CFX.sup.2—(CF.sub.2).sub.n-4—CF.sub.2X.sup.1 (2), wherein n is the same as above, X.sup.1 is the same or different and is a halogen atom other than fluorine, and X.sup.2 is a halogen atom, the perfluoroalkadiene compound can be obtained at a high yield.

An object of the present invention is to provide a simple, low-cost, and industrial method of producing a compound having a polyene skeleton containing hydrogen and fluorine and/or chlorine.

A method of producing a halogenated diene represented by formula (1): A.sup.1A.sup.2CCA.sup.3-CA.sup.4CA.sup.5A.sup.6[A.sup.1, A.sup.2, A.sup.5, and A.sup.6 are each independently hydrogen, fluorine, chlorine, a (perfluoro)alkyl group having 1 to 3 carbon atoms, or a (perfluoro)alkenyl group; A.sup.3 and A.sup.4 are each independently hydrogen, fluorine, or chlorine; at least one of A.sup.1 to A.sup.6 is hydrogen; at least one of A.sup.1 to A.sup.6 is fluorine or chlorine] comprises a step of subjecting the same or different halogenated olefin(s) represented by formula (2): A.sup.7A.sup.8CCA.sup.9X[A.sup.7 and A.sup.8 are each independently hydrogen, fluorine, chlorine, a (perfluoro)alkyl group having 1 to 3 carbon atoms, or a (perfluoro)alkenyl group; A.sup.9 is each independently hydrogen, fluorine, or chlorine; X is bromine or iodine] to a coupling reaction in the presence of a zero-valent metal and a metal salt.

An object of the present invention is to provide a simple, low-cost, and industrial method of producing a compound having a polyene skeleton containing hydrogen and fluorine and/or chlorine.

A method of producing a halogenated diene represented by formula (1): A.sup.1A.sup.2CCA.sup.3-CA.sup.4CA.sup.5A.sup.6[A.sup.1, A.sup.2, A.sup.5, and A.sup.6 are each independently hydrogen, fluorine, chlorine, a (perfluoro)alkyl group having 1 to 3 carbon atoms, or a (perfluoro)alkenyl group; A.sup.3 and A.sup.4 are each independently hydrogen, fluorine, or chlorine; at least one of A.sup.1 to A.sup.6 is hydrogen; at least one of A.sup.1 to A.sup.6 is fluorine or chlorine] comprises a step of subjecting the same or different halogenated olefin(s) represented by formula (2): A.sup.7A.sup.8CCA.sup.9X[A.sup.7 and A.sup.8 are each independently hydrogen, fluorine, chlorine, a (perfluoro)alkyl group having 1 to 3 carbon atoms, or a (perfluoro)alkenyl group; A.sup.9 is each independently hydrogen, fluorine, or chlorine; X is bromine or iodine] to a coupling reaction in the presence of a zero-valent metal and a metal salt.

Provided is a method for producing hexafluoro-1,3-butadiene, and the method can produce hexafluoro-1,3-butadiene at an industrially sufficient level of yield. In a reaction liquid containing a halogenated butane represented by chemical formula, CF.sub.2X.sup.1CFX.sup.2CFX.sup.3CF.sub.2X.sup.4 (X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are each independently a halogen atom other than a fluorine atom), zinc, and an organic solvent, a reaction is conducted to eliminate the halogen atoms other than a fluorine atom, X.sup.1, X.sup.2, X.sup.3, and X.sup.4, from the halogenated butane, yielding hexafluoro-1,3-butadiene. During the reaction, the concentration of a zinc halide generated by the reaction, in the reaction liquid is not more than the solubility of the zinc halide in the organic solvent.