Interconversion of Phosphinyl Radical and Phosphinidene Complexes by Proton Coupled Electron Transfer

Abstract

The isolable complex [Os(PHMes*)H(PNP)] (Mes*=2,4,6-tBu3C6H3; PNP=N{CHCHPtBu2}2) exhibits high phosphinyl radical character. This compound offers access to the phosphinidene complex [Os(PMes*)H(PNP)] by P−H proton coupled electron transfer (PCET). The P−H bond dissociation energy (BDE) was determined by isothermal titration calorimetry and supporting DFT computations. The phosphinidene product exhibits electrophilic reactivity as demonstrated by intramolecular C−H activation.