Lewis Acid Promoted Coupling Reactions of Acid Chlorides with Organoaluminum and Organozinc Reagents.

An efficient synthesis of α,β-unsaturated ketones by the reaction of acid chlorides with trialkylaluminum (1/3 mole equiv) in the presence of AlCl3 (1 mol equiv) is described. Dialkylzincs were also useful and are easier to prepare than trialkylaluminum. Reaction of RCOCl with R‘AlCl2 or R‘2AlCl gave R‘COR, without AlCl3, in high yield.