A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I) as described herein and further reactions with this compound.

A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I) as described herein and further reactions with this compound.

A method of forming chloro-substituted silanes from the reaction of an alkoxysilane with a chlorinating agent in the optional presence of a catalyst is provided. More specifically, chloro-substituted silanes, including but not limited to silicon tetrachloride, are formed by reacting a chlorinating agent, such as thionyl chloride, with an alkylalkoxysilane having the formula (R′O).sub.4-xSiR.sub.x, where R and R′ are independently selected alkyl groups comprising one or more carbon atoms and x is 0, 1, 2, or 3. The catalyst may be dimethylformamide, (chloromethylene)dimethyliminium chloride, or triethylamine, among others. The chloro-substituted silane formed in the reaction along with several by-products has the formula (R′O).sub.4-x-ySiR.sub.xCl.sub.y; where x is 0, 1, 2, or 3 and y is 1, 2, 3, or 4. One of the by-products of the reaction is an alkyl chloride.

A method of forming chloro-substituted silanes from the reaction of an alkoxysilane with a chlorinating agent in the optional presence of a catalyst is provided. More specifically, chloro-substituted silanes, including but not limited to silicon tetrachloride, are formed by reacting a chlorinating agent, such as thionyl chloride, with an alkylalkoxysilane having the formula (R′O).sub.4-xSiR.sub.x, where R and R′ are independently selected alkyl groups comprising one or more carbon atoms and x is 0, 1, 2, or 3. The catalyst may be dimethylformamide, (chloromethylene)dimethyliminium chloride, or triethylamine, among others. The chloro-substituted silane formed in the reaction along with several by-products has the formula (R′O).sub.4-x-ySiR.sub.xCl.sub.y; where x is 0, 1, 2, or 3 and y is 1, 2, 3, or 4. One of the by-products of the reaction is an alkyl chloride.

An industrially excellent production method for cycloalkyl(trifluoromethyl)benzene is free of complicated steps, small in the number of steps, and high in production efficiency. Cycloalkyl(trifluoromethyl)benzene is produced by reacting a halogen-substituted trifluoromethyl benzene with magnesium metal to produce a Grignard reagent and cross-coupling the Grignard reagent with a cycloalkyl halide in the presence of an iron salt or a cobalt salt at a reaction temperature of 60° C. to 80° C.

An industrially excellent production method for cycloalkyl(trifluoromethyl)benzene is free of complicated steps, small in the number of steps, and high in production efficiency. Cycloalkyl(trifluoromethyl)benzene is produced by reacting a halogen-substituted trifluoromethyl benzene with magnesium metal to produce a Grignard reagent and cross-coupling the Grignard reagent with a cycloalkyl halide in the presence of an iron salt or a cobalt salt at a reaction temperature of 60° C. to 80° C.

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.2C═CA.sup.3-CA.sup.4=CA.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.8C═CA.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 industrially excellent production method for cycloalkyl(trifluoromethyl)benzene is free of complicated steps, small in the number of steps, and high in production efficiency. Cycloalkyl(trifluoromethyl)benzene is produced by reacting a halogen-substituted trifluoromethyl benzene with magnesium metal to produce a Grignard reagent and cross-coupling the Grignard reagent with a cycloalkyl halide in the presence of an iron salt or a cobalt salt at a reaction temperature of 60 C. to 80 C.

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 an industrially simple and cheap method for efficiently removing butene from crude monofluorobutane containing butene without causing substantial decomposition, transformation, or the like of the monofluorobutane. In a provided monofluorobutane purification method, crude monofluorobutane containing butene is brought into contact with trihalomethane in the presence of an alkali aqueous solution to convert the butene to a compound having a higher boiling point than the monofluorobutane, water is subsequently added to a reaction mixture obtained thereby to dissolve a produced salt, an organic layer is separated, and then the separated organic layer is purified by distillation.