Visible Light Mediated Cyclization of Ynones for the Synthesis of 3‐Alkyl N‐Fused Indoles via Csp3−H Bond Functionalization

Abstract A visible‐light induced approach has enabled the synthesis of 3‐alkyl indole from ynones via C sp 3 −H bond functionalization. This protocol proceeded under base‐free conditions andat room temperature, providing a series of 3‐alkyl indole motifs in 39% to 90% yields (44 examples). Preliminary mechanistic studies suggest that a radical process should be involved in this transformation.