The present invention relates to a process for the preparation of a compound of formula I (I), comprising reacting a compound of formula II (II), with a brominating agent in the presence of an acidic catalyst to a compound of formula III (III), and reacting the compound of formula III in tetrahydrofuran or 2-methyl-tetrahydrofuran with potassium tert-butoxide to a compound of formula I.

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The present invention aims to provide an efficient method for obtaining a desired isomer of HFO-1132 from a composition comprising trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)). The present invention provides, as a means for solving the problem, a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising steps (1) to (3): (1) supplying a composition comprising HFO-1132(E) and/or HFO-1132(Z) to a reactor filled with a catalyst to perform an isomerization reaction between the HFO-1132(E) and the HFO-1132(Z); (2) separating the reaction product obtained in step (1) into a first stream comprising the HFO-1132(E) as a main component, and a second stream comprising the HFO-1132(Z) as a main component; and (3) recycling the first stream or the second stream obtained in step (2) to the reactor, to subject the first stream or the second stream to the isomerization reaction.

The present invention aims to provide an efficient method for obtaining a desired isomer of HFO-1132 from a composition comprising trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)). The present invention provides, as a means for solving the problem, a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising steps (1) to (3): (1) supplying a composition comprising HFO-1132(E) and/or HFO-1132(Z) to a reactor filled with a catalyst to perform an isomerization reaction between the HFO-1132(E) and the HFO-1132(Z); (2) separating the reaction product obtained in step (1) into a first stream comprising the HFO-1132(E) as a main component, and a second stream comprising the HFO-1132(Z) as a main component; and (3) recycling the first stream or the second stream obtained in step (2) to the reactor, to subject the first stream or the second stream to the isomerization reaction.

The present invention aims to provide an efficient method for obtaining a desired isomer of HFO-1132 from a composition comprising trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)). The present invention provides, as a means for solving the problem, a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising steps (1) to (3): (1) supplying a composition comprising HFO-1132(E) and/or HFO-1132(Z) to a reactor filled with a catalyst to perform an isomerization reaction between the HFO-1132(E) and the HFO-1132(Z); (2) separating the reaction product obtained in step (1) into a first stream comprising the HFO-1132(E) as a main component, and a second stream comprising the HFO-1132(Z) as a main component; and (3) recycling the first stream or the second stream obtained in step (2) to the reactor, to subject the first stream or the second stream to the isomerization reaction.

Provided is a method for obtaining HFO-1132(E) and/or HFO-1132(Z) efficiently. The method is a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising supplying a composition containing HFO-1132(E) and/or HFO-1132(Z) to a reactor, and performing an isomerization reaction between HFO-1132(E) and HFO-1132(Z).

Provided is a method for obtaining HFO-1132(E) and/or HFO-1132(Z) efficiently. The method is a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising supplying a composition containing HFO-1132(E) and/or HFO-1132(Z) to a reactor, and performing an isomerization reaction between HFO-1132(E) and HFO-1132(Z).

Provided is a method for obtaining HFO-1132(E) and/or HFO-1132(Z) efficiently. The method is a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising supplying a composition containing HFO-1132(E) and/or HFO-1132(Z) to a reactor, and performing an isomerization reaction between HFO-1132(E) and HFO-1132(Z).

A fluoropropene composition comprising Z-1,3,3,3-tetrafluoropropene, E-1,3,3,3-tetrafluoropropene, 2,3,3,3-tetrafluoropropene, and optionally 1,1,1,3,3-pentafluoropropane wherein the 2,3,3,3-tetrafluoropropene being present in an amount of 0.001 to 1.0%. A method of producing the fluoropropene, methods for using the fluoropropene and the composition formed are also disclosed.

A fluoropropene composition comprising Z-1,3,3,3-tetrafluoropropene, E-1,3,3,3-tetrafluoropropene, 2,3,3,3-tetrafluoropropene, and optionally 1,1,1,3,3-pentafluoropropane wherein the 2,3,3,3-tetrafluoropropene being present in an amount of 0.001 to 1.0%. A method of producing the fluoropropene, methods for using the fluoropropene and the composition formed are also disclosed.

A method for synthesizing 2-(1-cyclohexenyl)ethylamine. Cyclohexanone (II) is reacted with a Grignard reagent in a first organic solvent to produce 1-vinylcyclohexanol (III), which is then subjected to chlorination and rearrangement reaction with a chlorinating reagent in a second organic solvent in the presence of an organic base to synthesize (2-chloroethylmethylene)cyclolxane (IV). Then (2-chloroethylmethylene)cyclohexane (IV) and urotropine are subjected to quaternization in a third organic solvent to synthesize N-cyclohexylidene ethyl urotropine hydrochloride (V). Finally, the N-cyclohexylidene ethyl urotropine hydrochloride (V) undergoes hydrolysis and rearrangement reaction in a solvent in the presence of an inorganic mineral acid to synthesize 2-(1-cyclohexenyl)ethylamine (I).