Electrochemical Synthesis of 5-Aryl-phenanthridin-6-one by Dehydrogenative N,C Bond Formation.

Currently, the general synthesis of 5-aryl-phenanthridin-6-ones relies on the involvement of metal catalysis. Despite the urgent demand for green alternatives, avoiding synthetic routes that require transition metals for key roles is still challenging. Electrochemical efforts employing a constant potential protocol in divided cells revealed a possible alternative to the catalytic approach. A constant current protocol, undivided cells, and a remarkably low supporting electrolyte concentration enable a novel access to N-aryl-phenanthridin-6-ones by anodic N,C bond formation using directly generated amidyl radicals. Easy accessible starting materials, a broad scope of applicable functional groups, good yields, and a very simple set-up are the benefits of this sustainable method.