Selective B(3)-H Activation Affording Multinuclear Ir(III) Complexes with (o-Carboranyl)dithioester Ligands.

A method was developed to link two or three o-carborane moieties to form a series of carboranyl dithioester bridging ligands via in situ substitution of haloalkanes by tetraphenylphosphonium carboranyldithiocarboxylates. Based on these ligands, direct B-H activation without the assistance of Ag(I) and alkali was successfully achieved with half-sandwich Ir(III) substrate [Cp*IrCl 2 ] 2 to yield corresponding bimetallic or trimetallic complexes. Single crystal structure analyses of the B-H activated complexes and corresponding SnCl 2 -inserted derivatives confirm the selective B(3)-H activation in these complexes.