Chromium(II) reduction of trichloromethyl carbinols and their corresponding ethers: one-step synthesis of Z-vinyl chlorides

Abstract

Secondary trichloromethyl carbinols and their corresponding ethers can be reduced by chemically or electrochemically generated chromium(II) chloride to form Z-monochlorovinyl compounds in one step. In the presence of a carboxy function in the α-position an E-double bond is formed. Tertiary carbinols favour the formation of dichlorovinyl compounds and rearranged carbonyl compounds. Product ratios can be altered drastically by a change in the reaction conditions; this sheds light on the reaction mechanism.