Process for the preparation of 3-difluoromethyl-1-methy1-1H-Pvrazole-4- carboxylic acid (9-dichloromethylene-1,2,3,4-tetrahydro-1,4-methanonaphthalen-5-y1 )-amide

Abstract

The invention relates to a novel process for the production of 3-difluoromethyl-1- methyl-1H-pyrazole-4-carboxylic acid (9-dichlorom ethylene-1,2,3,4-tetrahydro-1,4-methano-naphthalen-5-yl)-amide of formula I that makes it possible to prepare said compound in high yields and good quality in an economically advantageous way, which process comprises a) reacting a compound of formula II wherein X is chloro or bromo, with an organometallic species to III reacting the halobenzyne of formula lllso formed with IV wherein R1 and R2 are hydrogen or C1-C6alkyl, to V wherein R1 and R2 are independently hydrogen or C1-C6alkyl and X is chloro or bromo; b) hydrogenating V in the presence of a metal catalyst to VI (c) ozonising VI to VII d) converting VII in the presence of a Triphenyl phosphane and CCI4 or CHCI3 to VIII e1 > reacting VIII with NH3 in the presence of a catalyst to IX and f) reacting IX in the presence of a base with the compound of formula X to the compound of formula I.