Visible-light-induced trifluoromethylation/cyclization of unactivated alkenes: Synthesis of CF3-substituted fused tricyclic indoles

Abstract

A visible-light-induced radical trifluoromethylation/cyclization of unactivated alkenes for the construction of trifluoromethylated tricyclic indoles with readily accessible trifluoromethyl thianthrenium triflate has been reported. A variety of CF₃-containing tricyclic indole derivatives were synthesized at room temperature without the addition of photocatalysts or additives. Mechanistic investigations indicate that the reaction probably undergo a radical pathway.