Simple synthesis of 2-alkenyl- and 2-aryl-substituted 1,1-dichloroethylenes from unsaturated aldehydes
A three-step synthesis has been proposed for the preparation of 2-alkenyl- and 2-aryl-1,1-dichloroethylenes, involving the conversion of an aldehyde to its acylal (or α-trichloromethylcarbinol), α-trichloromethylcarbinol acetate, and 2-substituted 1,1-dichloro-olefin. The best procedure for the dechloroacetoxylation by the action of zinc powder in a mixture of acetic acid and ether.
Electrochemical Wittig reaction. Part I. Synthesis of gem-dichloroalkenes
Two-electron electrochemical reduction of trichloromethyl tris(dimethylamino)phosphonium tetrafluoroborate led to dichloromethylene tris(dimethylamino)phosphorane, which was reacted with an aromatic or aliphatic aldehyde, to give gem-dichloroalkenes in go