First evidence for a curtius type rearrangement involving a charged atom. An easy synthesis of an iminophosphonium salt

Abstract

Irradiation of azidophosphonium salts (Me2N)3P+N3,X–(1;X= PF6)and (4;X= Br)leads either to an iminophosphonium salt (Me2N)2P+N–NMe2,PF6–(2)or to an iminophosphorane (Me2N)3PNH(7)depending on the nature of the anion; these differences in the photochemical behaviour of (1)and (4)are rationalized by the transient existence of a phosphonitrenium salt (Me2N)3PN+X–(8).