New nitrogenated siloxy butadienes from 1,3-dichloroacetone

New 1-formamido-2-siloxy-1,3-butadienes have been generated from 1,3-dichloroacetone by means of phosphorane formation, formamido substitution, Wittig olefination and silylation. The procedure demonstrates the utility and versatility of this methodology for the formation of polysubstituted dienes, designed as useful building blocks for the synthesis of polycyclic alkaloids and related analogues.