N-Bromosuccinimide-Induced C–H Bond Functionalization: An Intramolecular Cycloaromatization of Electron Withdrawing Group Substituted 1-Biphenyl-2-ylethanone for the Synthesis of 10-Phenanthrenol

An NBS-induced intramolecular cycloaromatization for the synthesis of 10-phenanthrenols from electron-withdrawing group substituted 1-biphenyl-2-ylethanones is described. The in situ generated bromide was designed to act as an initiator for the radical C–H bond activation. An oxidative cross-dehydrogenative coupling reaction of a highly active C–H bond with an inert C–H bond readily occurs under mild conditions without the need for transition metals or strong oxidants.