Metal-Free Halogen Atom Transfer for Carbocyclization of N-Arylacrylamides Enabled by Visible Light-Excited Ligated Boryl Radical

Abstract

A visible light-induced, metal-free method for synthesizing 3,3-dialkylated oxindoles via boryl radical-mediated halogen atom transfer is described. This approach enables carbocyclization of N-arylacrylamides under ambient air using an organic photosensitizer and NHC-BH3, accommodating both alkyl and aryl halides. The practicality of this protocol is demonstrated through facile scalability and applications in drug synthesis.