Gas-Phase Dehydrogenation of Alkanes: C-H Activation by a Graphene-Supported Nickel Single-Atom Catalyst Model

A gas-phase anionic nickel(0) fluorenyl complex is shown to effect the dehydrogenation of linear, branched, and cyclic alkanes via C-H activation. It performs dehydrogenations via a C-H insertion followed by β-hydride elimination. When given energy via collision-induced dissociation, the system is capable of second and third dehydrogenations to form dienes and aromatics such as benzene. Kinetic isotope effects and DFT calculations completed at the M06/6-311+G** level support the proposed mechanism. The metal complex can act as an experimental model for graphene-supported nickel single-atom catalysts and suggests that these catalysts are capable of alkane dehydrogenation via C-H activation.