A Novel Formation of Phenyl-Substituted Pyridines by the Reaction of N-(Diphenylphosphinyl)-1-azaallyl Anions with α,β-Unsaturated Carbonyl Compounds. A New Synthetic Equivalent of Primary Vinylamines

The N-phosphinyl-1-azaallyl anions, which were derived from the corresponding imine or enamine, reacted with α,β-unsaturated carbonyl compounds to afford phenyl-substituted pyridines along with 1-propanone and 1,5-pentanedione derivatives. A plausible mechanism involving a sequence of Michael addition and intramolecular aza-Horner-Wittig reaction is described, and the 1-azaallyl anions were found to behave as a synthetic equivalent of primary vinylamines.