Iron-mediated divergent reductive coupling reactions of heteroarenes with alkenes†

Iron-mediated divergent reductive coupling reactions of heteroarenes with alkenes have been developed. By switching the substituent site at the C2 and C4 positions of quinolines, either C2 Minisci alkylation or C4 reductive alkylation could be achieved. These approaches feature mild conditions and sensitive functional group tolerance, which enables the functionalization of natural products and medicines. Mechanism investigation revealed that Fe(dibm)₃ would be a dual promoter for both alkyl radical transfer and generation of the more reactive hydrogen donor Ph(RO)SiH_2.