Process for preparing high cis 3-(2,2,2-trichloroethyl)-2,2-dimethylcyclopropane-1-carboxylates
申请人:FMC Corporation
公开号:EP0003683A2
公开(公告)日:1979-08-22
A process is described whereby esters of 3-(2,2,2-trichloroethyl) - 2,2- dimethylcyclopropane - 1 - carboxylic acid are prepared predominantly in their cis isomer form. The process comprises treating a 4,6,6,6-tetrachloro-3,3-dimethylhexanoate with an alkali metal tert-alkoxide under controlled conditions of temperature in the presence of a defined solvent-cosolvent mixture. The products of the process are intermediates in the production of pyrethroid insecticides.
Isomer enrichment process for cyclopropane carboxylates
申请人:ICI AMERICAS INC.
公开号:EP0074792A1
公开(公告)日:1983-03-23
A method of partially resolving the cis and trans isomers of a cyclopropane carboxylate by a controlled partial hydrolysis. The cis/trans distribution in the hydrolyzed product differs from that in the starting material. The cyclopropane carboxylates are known intermediates for the natural and synthetic pyrethroids, some of which exhibit a difference in pesticidal activity depending on whether the cis or trans isomers are applied.