A new simple and efficient transformation of aromatic aldehydes into α-chlorocinnamaldehydes is described. Catalytic olefination reaction of hydrazones of aromatic aldehydes with 2-trichloromethyl-1,3-dioxolane gives ethylene acetals of target alkenes in moderate to good yields. The reaction proceeds stereoselectively to form preferably Z-isomers.
catalytic olefination - α-chlorocinnamaldehydes - catalysis - alkenes - 2-trichloromethyl-1,3-dioxolane
