N-(Diphenylphosphinothioyl)hydroxylamine: preparation, characterisation and base-induced transposition of sulfur and oxygen atoms in its O-benzoyl derivative1

Abstract

N-(Diphenylphosphinothioyl)hydroxylamine 5 has been prepared from Ph₂P(S)Cl using H₂NOSiMe₃ and has been converted into its O-benzoyl derivative Ph₂P(S)NHOCOPh 6. The principal reaction of the derivative 6 with base (NaOMe or Bu^tNH₂) is rearrangement, transposition of sulfur and oxygen giving Ph₂P(O)NHSCOPh 7; this then reacts further, forming the phosphinic amide Ph₂P(O)NH₂ together with PhCO₂Me or PhCONHBu^t. The rearrangement probably involves intramolecular nucleophilic displacement of benzoate by the PS group of 6, forming an intermediate with P, N and S atoms in a three-membered ring.