Visible-Light-Induced Radical Relay Trifluoromethylation/Cyclization of N-Cyanamide with Internal Alkenes: Access to Trifluoromethylated Polycyclic Quinazolinones

A visible-light-induced radical relay trifluoromethylation/cyclization reaction between N-cyano-N-isopentenyl arylamide or (E)-N-cinnamyl-N-cyanoarylamide with CF3Br has been developed, affording trifluoromethylated dihydropyrroloquinazolinone derivatives in good yields. A key feature of this method is the regioselective addition of the trifluoromethyl radical to the internal C=C bond of N-cyano-N-isopentenyl arylamides and (E)-N-cinnamyl-N-cyanoarylamides, which directly incorporates a trifluoromethyl group into the pyrrolidine ring of the dihydropyrroloquinazolinones. Mechanistic studies suggest a radical-mediated pathway. The broad substrate scope, excellent functional group tolerance, and use of green energy are expected to enhance its potential applications in pharmaceutical chemistry.