Photo-Induced Difluoroethylation or Monofluoromethyl Sulfonylation of 2-Amino Aryl Ethynes to Access Diverse Seven-Membered N-Heterocycles

Abstract

A photo-induced two/three-component radical difluoroethylation or monofluoromethyl sulfonylation of 2-amino aryl ethynes was smoothly finished, which gave a series of difluoroethyl or monofluoromethyl sulfonyl seven-membered N-heterocycles. The two radical systems featured simple/mild reaction conditions, good substrate scopes, and excellent E/Z selectivity. In addition, various radical intermediates were successfully detected by HRMS to explore the reaction process. Single-crystal X-ray diffraction and scaled-up experiments examined the product scaffold and application of this cyclization system.