Oxidative addition of methane and benzene C–H bonds to rhodium center: A DFT study

A density functional theory study on mechanisms of the oxidative addition of methane and benzene C–H bonds to the rhodium center containing Cp and PMe3 ligands has been performed. Our calculated results confirm that the C–H bond cleavage from a sigma complex to a hydride alkyl complex is the rate-determining step. Compared with the case of methane C–H bond, the oxidative addition of benzene C–H bond is more favorable kinetically and thermodynamically. Stronger backdonation from metal center to the σ∗ antibonding orbital of benzene C–H bond is responsible for the observations.