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).