Site-Specific Oxidative C-H Chalcogenation of (Hetero)Aryl-Fused Cyclic Amines Enabled by Nanocobalt Oxides.

By employing reusable nanocobalt oxides as the catalysts, a site-specific oxidative C-H chalcogenation of (hetero)aryl-fused cyclic amines with various thiols and diselenides is presented for the first time. The reaction proceeds selectively at the sites of the (hetero)aryl rings para to the N atom, and enables access to a wide array of chalcogenyl N-heteroarenes. The merits of the transformation involve high step- and atom-efficiency, excellent substrate and functional compatibility, operational simplicity, and the use of a naturally abundant Co/O2 system. The present work has offered a fundamental basis for the selective synthesis of functional N-heteroarenes from readily available feedstocks.