Gas Phase Basicity of Hexamethylphosphotriamide (HMPT) and Phosphinoxide Derivatives

Abstract

Abstract Gas phase basicities are determined by Ion Cyclotron Resonance (ICR) mass spectrometry for the six organophosphorus compounds OP(NMe2)3-x Me x x=0 to 3, OP(nPr)3 and OP(OEt)3. All values are in the range 209–219.3 kcal · mol−1, and their variation with structure is examined. The site of protonation (O or N?) is briefly discussed, and arguments are presented which favour O-protonation.