C(sp3)–H Bond Activation Induced by Monohydroborane Coordination at an Iridium(III)–Phosphoramidate Complex. Issue 20 (13th February 2017) - Drover, Marcus W.
Abstract : The reaction of Cp*Ir III phosphoramidate (Cp* = pentamethylcyclopentadienyl) complexes with a monohydroborane (HBR2 ; R = cyclohexyl or mesityl) generates cyclometalated Cp*Ir III complexes following two sequential intramolecular B–H and C(sp 3 )–H bond‐activation events. Preliminary mechanistic inquiry suggests that boron stabilization provided by the hemilabile phosphoramidate ligand provides a δ ‐B–H··· [Ir] coordinated intermediate, which succumbs to borane‐induced C(sp 3 )–H bond activation. Abstract : Two is better than one to generate cyclometalated Cp*Ir III phosphoramidate complexes by sequential intramolecular B–H and C(sp 3 )–H bond‐activation events. Such complexes represent a first step in an overall Ir‐catalyzed process for organophosphate functionalization. Cp* = pentamethylcyclopentadienyl; Mes = mesityl.