Nature of the bonding in a carbene–phosphinidene: a main group analogue of a Fischer carbene complex? Isolation and characterisation of a bis(borane) adduct

Abstract

The reaction of the carbene–phosphinidene (1,3-dimesitylimidazolin-2-ylidene)PPh 1 with BH ₃ ·thf affords the corresponding P-bonded bis(borane) adduct, thus demonstrating the availability of two lone pairs on the phosphorus centre; base competition studies reveal that 1 is a strong phosphorus base and, by means of cyclic voltammetry, it is established that 1 undergoes facile oxidation.