Photo-Driven Regiodivergent Arylation/Cyclization and Arylation/Hydroxylation of <i>N</i>-Aryl Methacrylamides with Aryltriazenes: Access to Functionalized 3,3-Disubstituted Oxindoles and α-Hydroxylamides

Abstract

A metal-free, light-induced regiodivergent functionalization of α,β-unsaturated amides with aryltriazenes under ambient conditions was developed. The visible light and B(C 6 F 5 ) 3 cocatalyzed radical cascade arylation/cyclization of N -alkyl- N -arylmethacrylamides can obtain functionalized 3,3-disubstituted oxindoles with the assistance of photocatalyst eosin Y–Na 2 . In the absence of any catalyst, with purple light irradiation and electron-donor–acceptor (EDA) complex initiation, the radical cascade arylation/hydroxylation of N -arylmethacrylamides affords α-hydroxylamides. This methodology highlights the arts in accessing different regioisomers by altering the substrates and photocatalytic strategies.