Iron-Catalyzed Triazole-Enabled C–H Activation with Bicyclopropylidenes

C–H/C–C functionalizations with oxymethylated bicyclopropylidenes were accomplished with an iron catalyst under external oxidant-free conditions. The combination of the unique reactivity of bicyclopropylidenes with a robust iron­(II) catalyst enabled C–C cleavages in a chemoselective fashion, which allows for the synthesis of isoquinolones, free isoquinolones, or bispiro-fused isoquinolones. Mechanistic studies provided strong support for the C–C cleavage via β-C elimination. A rare monoselective C–F/C–H bond functionalization of trifluoromethylarene was also observed.