Tunable Redox‐Neutral Photocatalysis: Visible Light‐Induced Arylperfluoroalkylation of Alkenes Regulated by Protons

Abstract A redox entanglement in photoredox catalysis is discovered and discussed. Using MeOH as a proton source and Eosin Y as a photocatalyst, a problematic and redox‐neutral perfluoroalkylation/cyclization cascade of alkenes with perfluoroalkyl iodides can be streamlined, furnishing perfluoroalkylated indolines, indoles, dihydroisoquinolinones, and indolin‐2‐ones with a good functional‐group tolerance under base‐, metal‐, and redox‐agent‐free conditions. Mechanistic investigations revealed that MeOH does not activate the perfluoroalkyl C−I bond, but rather enhances the oxidation part of the photocatalytic cycle.