2,2'-Dichloro-4',5'-difluoroacetophenone and process for its preparation, its application to the preparation of 2-chloro-4,5-difluorobenzoic acid and new process for the preparation of the said acid

摘要

The invention relates to 2,2'-dichloro-4,5'-difluoroacetophenone, of formula: <IMAGE> which is used as an intermediate in the synthesis of 2-chloro-4,5-difluorobenzoic acid by reacting sodium hypochlorite with 2,2'-dichloro-4',5'-difluoroacetophenone. This ketone is obtained from 3,4-difluorochlorobenzene, which is reacted with chloroacetyl chloride or chloroacetic anhydride in the presence of a Lewis salt.