STEREOCHEMISTRY OF ELECTROREDUCTIONS .2. GEMINAL DIHALOCYCLOPROPANES

Stereochemical correlations between electrochemical (mercury electrode) and zinc or lithium amalgam reductions have been found to hold for geminal dihalocyclopropanes. The reductions of the isomers of 7-bromo-7-chloro[4.1.0]bicycloheptane result in exclusive removal of the bromine with predominant retention of configuration. Results are discussed within a common mechanism for electrochemical and metallic reductions. It is suggested that reductions of geminal dibromo- or dichlorocyclopropanes may occur at either halogen atom rather than just on the exo halogen. © 1969, American Chemical Society. All rights reserved.