2‐Azaallyl Anions as Light‐Tunable Super‐Electron‐Donors: Coupling with Aryl Fluorides, Chlorides, and Bromides

Abstract Herein, we present 2‐azaallyl anions as colored super‐electron‐donors capable of reducing a collection of aryl halides via a single electron transfer and coupling with the corresponding radicals to forge new C−C bonds. This offers a robust approach for the arylation of 2‐azaallyls. Mechanistic studies demonstrate that the reactions proceed via either a radical pathway for aryl bromides and chlorides or a S N Ar mechanism for activated aryl fluorides. Moreover, we demonstrate that irradiation of the colored 2‐azaallyl anions with visible light can further extend their reducing power, enabling radical‐mediated coupling with otherwise unreactive electron‐rich aryl halides. Isolated yields up to 94% are obtained and the overall relevance and utility is demonstrated by the derivatization of both a known pharmaceutical agent and a popular fluorophore. magnified image