Copper-catalysed radical cyclization from phenylboronic acid and N-acryloyl indole or benzimidazole derivatives with air as an oxidant

Abstract

Thermochemical oxidation of phenylboronic acids to form aryl radicals relies on stoichiometric amounts of Mn(OAc)₃ or peroxides as oxidants, which limits their practical utility. We herein report the copper-catalysed aerobic oxidation of phenylboronic acids for aryl radical generation, which initiates radical cyclization toward indolo/benzoimidazo[2,1-a]isoquinolinone derivatives.