Hydrogen Atom Abstraction by Heterogeneous-Homogeneous Hybrid Catalyst of CeO₂and 2-Cyanopyridine via Redox of CeO₂for C-H Bond Oxidation with Air

Hybrid catalysts composed of heterogeneous and homogeneous components are promising for obtaining unique catalysis and tuning and controlling the catalytic performance; however, the examples on the development and application of the hybrid catalysts are limited. Here, we present that the hybrid catalyst of CeO₂and 2-cyanopyridine can work as an H atom abstractor of C-H bonds in alkanes. The hybrid catalyst showed high activity for the oxidation of alkanes with air as an oxidant, providing high selectivity to the alcohols and ketones. The experimental studies and DFT calculations indicate that the N atom in the CN group of 2-cyanopyridine adsorbed on CeO₂can function like an N-radical center driven by the redox of CeO₂. The H atom was abstracted by the N atom in the CN group, which is induced by the reduction of Ce⁴⁺to Ce³⁺in CeO₂via the electron transfer.