Enamine synthesis using the <i>Horner‐Wittig</i> reaction. Part 2. New acyl anion equivalents derived from (aminomethyl)diphenylphosphine oxides

Abstract

Abstract Using the Horner‐Wittig reagents (1‐morpholino‐alkyl)diphenylphosphine oxides ( 1 ), aromatic as well as aliphatic and α, β‐unsaturated aldehydes can be converted into the morpholino enamines of their respective homologous phenyl, ethyl and styryl ketones. These enamines can be easily converted into the corresponding ketones by mild, acid‐catalyzed hydrolysis. The usefulness of these phosphine oxides as acyl anion equivalents is further demonstrated by the synthesis of dihydrojasmone and of (Z)‐6‐henicosen‐ll‐one.