New complexity for aromatic ring agostic interactions

Density functional theory (DFT) calculations reveal that for ligand directed aromatic ring C–H bond activation, the agostic donation can share the same antibonding acceptor orbitals as a previously unrecognised π-donation from the aromatic ring of the ligand. The recognition of carbon based orbitals assisting the agostic interaction has significant implication for C–H bond activation chemistry.