Phototriggered Fluoroalkylation/Cyclization of Unactivated 1‑Acryloyl-2-cyanoindoles: Synthesis of RCOCF₂‑Substituted Pyrrolo[1,2‑a]indolediones

A photochemical approach toward RCOCF₂-substituted pyrrolo­[1,2-a]­indolediones was developed by the radical cascade difluoroalkylation/cyclization reaction of unactivated 1-acryloyl-2-cyanoindoles with ethyl iododifluoroacetate or iododifluoramides under visible-light irradiation. This transition-metal- and photosensitizer-free protocol afforded diverse difluoroalkylated pyrrolo­[1,2-a]­indolediones in moderate to good yields under mild reaction conditions. Most appealingly, the reaction can proceed smoothly under sunlight irradiation, which opens a new avenue toward difluoroalkylated pyrrolo­[1,2-a]­indolediones.