N-Bromosuccinimide-Mediated Radical Cyclization Of 3-Arylallyl Azides: Synthesis Of 3-Substituted Quinolines

Visible light irradiation of N-bromosuccinimide serves as an effective means to convert methyl 2-(azidomethyl)-3-arylpropenoates and 2-(azidomethyl)-3-arylacrylonitriles to the corresponding iminyl radicals via a-hydrogen abstraction and subsequent extrusion of dinitrogen. Thus formed iminyl radicals then undergo intramolecular ortho attack on the aryl ring, affording methyl quinoline- 3-carboxylates and quinoline-3-carbonitriles respectively.