Visible-light-induced radical cascade cyclization of 1-(allyloxy)-2-(1-arylvinyl)benzenes with sulfonyl chlorides for the synthesis of sulfonated benzoxepines

Abstract

A visible light photocatalyzed cascade sulfonylation/cyclization of 1-(allyloxy)-2-(1-arylvinyl)benzenes with sulfonyl chlorides for the construction of sulfonated benzoxepines is developed. In the presence of Eosin Y (2.0 mol%) as a photocatalyst and Na₂CO₃ as a base, the reactions proceed smoothly to afford seven-membered rings in good yields. This transformation features wide substrate scope, the use of easily accessible materials and excellent functional group tolerance.