Tailoring the Coordination Environment of Cu Single Atoms for Achieving Regioselective C–C Bond Activation of Amides

Abstract

C–C bond activation can provide a direct reconstruction strategy of carbon skeletons to furnish a number of structurally diverse molecules. In general, regioselectivity represents the state-of-the-art owing to the existence of several different carbon–carbon bonds, having a high BDE, ∼90 kcal/mol. Here, we report a directed strategy for amides for the concise synthesis of a range of urea derivatives and carbamates via regioselective C–C bond activation enabled by the heterogeneous single-atom copper catalyst (Cu-SAC), with a turnover frequency of 249 h^–1, which is 19 times higher than that of the analogous homogeneous copper catalyst. Multitechnique characterization data show that single-atom Cu species are associated with an unsaturated coordination structure and plentiful oxygen vacancies on γ-Al₂O₃ that facilitate the adsorption of multiple coordinated amides and dioxygen, leading to high catalytic activity and selectivity. It would offer opportunities to speed up the heterogenized process of homogeneous catalysts in regioselective inert-bond activation reactions.