Donor-Engineered Photocatalyst Enables Noble-Metal-Free Dehydrogenative Amination of Cycloalkanones to Aromatic Amines

The exploration of noble-metal-free C(sp²)-N coupling reactions from nonaromatic precursors holds promise for drug development. Herein, we report a cascade catalytic system integrating a novel organic photocatalyst and a cobalt oxime complex, achieving the efficient dehydrogenative amination of aliphatic cycloalkanones to aromatic amines. By optimizing the donor strength of the photocatalyst under visible blue light irradiation, cycloalkanone-derived enamine intermediates undergo photo-oxidation followed by multistep dehydrogenative aromatization, producing structurally diverse anilines and heteroaromatic amines. Notably, this system delivers direct access to pharmaceutical intermediates in a single catalytic cascade, enabling the efficient synthesis of the anesthetic tetracaine and antidiabetic and tumor angiogenesis inhibitors under mild conditions, circumventing the potential toxicity risks of noble metals and avoiding harsh reaction environments.