Efficient Isomerization for Preparing thans-2,2-Dimethyl-3-(2,2-dichloroethenyl) cyclopropanecarbonyl Chloride

摘要

Trans-2,2-dimethyl-3-(2,2-dichloroethenyl)cyclopropanecarbonyl chloride, which is animportant intermediate for insecticides, is obtained by isomerization of the cis/trans-mixture with4- (N,N-dimethylamino) pyridine (DMAP) in the presence or absence of halogen compounds ingood yield.