Reactivity and chemoselectivity of primary Z-β-enamino-λ5-phosphazenes towards electrophiles

Abstract

The multifunctional character of Z-β-enamino-λ⁵-phosphazenes (2) towards several electrophiles is shown. Thus, while hydrogen or alkyl halides react through the PN double bond, affording β-enaminophosphonium salts (3) and (4), in the presence of a base, alkylation of the enamine moiety (6) occurs. Ethyl chloroformate acts as acylating agent of the enaminic nitrogen and with bromine and triethylamine, α-bromoenaminophosphazenes (8) are obtained.