Cobalt single-atom catalysts for domino reductive amination and amidation of levulinic acid and related molecules to N-heterocycles

The development of single- atom- based catalysts (SACs), which bridge the traditional areas of homogeneous and heterogeneous catalysis, continues to be important for achieving organic synthesis in a more efficient and practical manner. Here, we report reusable cobalt-based SACs for the selective and general reductive amination of levulinic acid and related keto acids, which is of interest in the context of valorization of biomass. The optimal Co-SAC-based catalyst is prepared by pyrolysis (800 degrees C) of cobalt-phenanthroline complexe on carbon and subsequent acid treatment. The resulting Co-SACs showed amazing activity compared with the corresponding Co-nanoparticles and displayed an excellent substrate scope for various reductive domino transformations including reactions of levulinic acid with nitro compounds and nitriles to produce various N-substituted pyrrolidones in good to excellent yields. Further, the synthesis of diverse isoindolinones from aromatic ketoacids and amines/nitro compounds was performed with the optimal catalyst system.

Automated summary

This article reports on reusable cobalt-based single-atom catalysts (SACs) for the selective and general reductive amination of levulinic acid and related keto acids. The catalyst exhibits impressive activity and a wide range of substrate applicability, effectively promoting reactions between levulinic acid and nitro compounds as well as nitriles, as well as facilitating the synthesis of isoindolinones from aromatic keto acids and amines/nitro compounds.