The scope and limitations of the reactions of dichlorocarbene and/or trichloromethide generated from sodium trichloroacetate in refluxing 1, 2-dimethoxyethane with a variety of aliphatic O-alkeynl esters and ethers, N-vinyl amides, and 1-haloalkenes are reported. All groups gave the gem-dichlorocyclopropanes with the sole exception of the O-vinyl carboxylates where only products of trichloromethide addition occurred or mixtures due to ...