| abstract |
The present invention relates to a process for preparing difluoromethyl-substituted pyrazol-4-yl carboxylates of the formula (I) in which R is C-C-alkyl, C-C-cycloalkyl, C-C-alkoxy-C-C-alkyl, etc.; and R is hydrogen, C-C-alkyl, benzyl or phenyl, wherein a) a compound of the general formula (II) in which X is fluorine, chlorine, or bromine, R has one of the definitions given above, and R is C-C-alkyl, C-C-cycloalkyl, C-C-alkenyl, benzyl or phenyl, is reacted with a silane compound of the general formula R SiClin which n is 1, 2 or 3 and the substituents R are each independently selected from C-C-alkyl and phenyl, and with a metal which is selected from the metals of groups 1, 2, 3, 4 and 12 of the periodic table and has a redox potential of less than -0.7 V, based on a standard hydrogen electrode (at 25°C and 101.325 kPa); and b) the reaction mixture from step a) is reacted with a compound of the general formula (III) in which R has one of the definitions given above. |