Insight into the Scope and Mechanism for Transmetallation of Hydrocarbyl Ligands on Complexes Relevant to C-H Activation

We report the transmetallation of hydrocarbyl fragments (Me, Bn, Ph) from a variety of organo-metallic complexes relevant to C-H activation (Ir, Rh, W, Mo) to Pt(II) electrophiles. The scope of suitable hydrocarbyl donors is remarkable in that three different classes of organometallics with widely varying reactivity all undergo the same general reaction with Pt(II) electrophiles. A competitive substituent effect experiment reveals faster transmetallation of more electron rich hydrocarbyl groups. A sterochemical probe reveals that transmetallation to Hg(II) proceeds with retention of stereochemistry. This study suggests that transmetallation could provide a viable path for catalytic function- alization of stable complexes resulting from C-H bond activation and other processes.