Photoredox-Enabled Chemo-Selective Construction of Indole-Fused Medium-Sized Difluoro-diazocines.

Fluorine-functionalized N-heterocycles are privileged structural motifs found in many high-value molecules. Nevertheless, tactics for the facile construction of fluorinated medium-sized N-heterocycles (ring size of ≥8) to date are not viable owing to their inherently unfavorable enthalpic and entropic nature. This work disclosed a novel photoredox-enabled chemo-selective difluoromethylation cyclization for the synthesis of indole-fused medium-sized difluoro-diazocines. Good substrate scope and functional group compatibility, biologically molecule derivatization, large-scale synthesis and C-3 selenylation, cyanation, halogenation, nitration, and cross-coupling highlight the utility of this photoredox catalysis protocol.