Regioselective alkylation reactions of hydrazones derived from phosphine oxides and phosphonates. Synthesis of phosphorus substituted 1-amino-pyrrolones, pyridinones and pyrroles

Functionalized hydrazones derived from phosphine oxides or phosphonates were obtained from azaenolates of hydrazones and alkyl halides. The regioselectivity of alkylation of a-phosphorylated hydrazones can be controlled by phosphorus moiety. alpha -Alkylated compounds were used for the synthesis of heterocycles such as 1-aminopyrrol-2-ones, 1-amino-3,4-dihydropyridin-2-ones and 1-amino-pyrroles containing phosphinyl or phosphoryl substituents. (C) 2001 Elsevier Science Ltd. All rights reserved.