Photo-driven haloazidation cyclization of 1,5-enynes having cyano groups with TMSN3 and NIS/NCS/NBS under metal-free conditions

Abstract

A visible-light-driven three-component haloazidation cyclization of 1,5-enynes having cyano groups with TMSN₃, and N-iodo(bromo, chloro)succinimide under metal-free and oxidant-free conditions was developed. The reaction underwent a radical addition/5-exo-dig cyclization/radical coupling process with the successive formation of C–N, C–C, and C–halogen (Cl, Br, and I) bonds, which was initiated by the addition of an azidyl radical to the carbon–carbon double bond of the 1,5-enyne.