反应详情

A fifth aspect of this invention is a process for the preparation of ethyl 3-cyclopropyl-2,2-difluoropropanoate, which process comprises: (a) reacting bromomethylcyclopropane with 2-carboethoxy-1,3-dithiane in the presence of strong base to give ethyl 2-(cyclopropylmethyl)-1,3-dithiane-2-carboxylate; (b) reacting the ethyl 2-(cyclopropylmethyl)-1,3-dithiane-2-carboxylate with N-bromosuccinimide to give ethyl 3-cyclopropyl-2-oxopropanoate; and (c) reacting the ethyl 3-cyclopropyl-2-oxopropanoate with a fluorinating agent.