Abstract: A method for purifying difluoroacetic acid chloride, including the step of bringing a difluoroacetic acid chloride composition that contains at least difluoroacetic acid fluoride into contact with calcium chloride at a temperature enabling reaction thereof thereby converting difluoroacetic acid fluoride into difluoroacetic acid chloride.

Abstract: A production method of difluoroacetyl chloride according to the present invention includes a chlorination step of bringing a raw material containing at least either a 1-alkoxy-1,1,2,2-tetrafluoroethane or difluoroacetyl chloride into contact with calcium chloride at a reaction enabling temperature. A production method of 2,2-difluoroethyl alcohol according to the present invention includes a catalytic reduction step of causing catalytic reduction of the difluoroacetyl chloride obtained by the above production method. By these methods, the difluoroacetyl fluoride can be efficiently converted to the difluoroacetyl chloride and to the 2,2-difluoroethyl alcohol.

Abstract: A method for producing a pyrazole compound of the general formula (5) includes reacting a 2-acyl-3-aminoacrylic acid ester of the general formula (1) with a hydrazine of the general formula (4) in the presence of a base where R1, R2, R3 and R4 each independently represent an alkyl group wherein R5 represents an alkyl group or an aryl group wherein R1, R4 and R5 have the same meanings as above. It is possible by this production method to produce the 1,3-disubstituted pyrazol-4-carboxylic acid ester at a high yield and selectivity and with less discoloration.

Abstract: Disclosed is a method for purifying a trans-1,3,3,3-tetrafluoropropene, in which a composition containing trans-1,3,3,3-tetrafluoropropene and at least one impurity selected from the group consisting of C2H3ClF2, CF3CH2CHClF, CF3CH2CHF2, CHF2CH?CF2, CF3CH?CHCl, CF3CH?CH2, CF3C?CH, and cis-1,3,3,3-tetrafluoropropene is brought into contact with a solid adsorbent to reduce an impurity content thereof. By this method, it is possible to remove the impurity in trans-1,3,3,3-tetrafluoropropene by a simple operation.

Abstract: A method for purifying difluoroacetic acid chloride, including the step of bringing a difluoroacetic acid chloride composition that contains at least difluoroacetic acid fluoride into contact with calcium chloride at a temperature enabling reaction thereof thereby converting difluoroacetic acid fluoride into difluoroacetic acid chloride.

Abstract: A production method of 1-chloro-3,3,3-trifluoropropene according to the present invention includes bringing a raw material composition containing 1,3,3,3-tetrafluoropropene and an acid composition containing hydrogen chloride into contact with each other in gas phase in the presence of a catalyst. This production method allows not only use of hydrogen chloride containing hydrogen fluoride, which has been generated during a preceding step (production of 1,1,1,3,3-pentafluoropropane as a raw material or analogues thereof), but also use of any of trans and cis isomers of the 1,1,1,3,3-pentafluoropropane for production of the 1-chloro-3,3,3-trifluoropropene. It is thus possible to efficiently produce the 1-chloro-3,3,3-trifluoropropene, which is known as an environment-adaptive chlorofluorocarbon. As the catalyst, preferred is an alumina catalyst treated by contact with hydrogen fluoride.

Abstract: A composition according to the present invention contains at least a triarylamine compound and at least one bicyclic compound selected from the group consisting of those of the general formulas [1] to [4], wherein the triaryl amine compound is dissolved in the at least one bicyclic compound where R1 each independently represents a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a fluorine atom or a chlorine atom; A, B, C and F each independently represents either —CR22—, —O— or —NR2—; D and E each independently represents either —CR2? or —N?; G represents —CR22—; H represents —CR2?; and R2 represents a hydrogen atom, a methyl group or a halogen atom.

Abstract: A production method of difluoroacetyl chloride according to the present invention includes a chlorination step of bringing a raw material containing at least either a 1-alkoxy-1,1,2,2-tetrafluoroethane or difluoroacetyl chloride into contact with calcium chloride at a reaction enabling temperature. A production method of 2,2-difluoroethyl alcohol according to the present invention includes a catalytic reduction step of causing catalytic reduction of the difluoroacetyl chloride obtained by the above production method. By these methods, the difluoroacetyl fluoride can be efficiently converted to the difluoroacetyl chloride and to the 2,2-difluoroethyl alcohol.