Visible-Light-Mediated Fluoroalkylation of Isocyanides with Ethyl Bromofluoroacetates: Unified Synthesis of Mono- and Difluoromethylated Phenanthridine Derivatives

A practical and unified strategy has been described for the preparation of mono- and difluoromethylated phenanthridine derivatives using a visible-light-promoted alkylation and decarboxylation sequence from biphenyl isocyanides with ethyl bromofluoroacetate (EBFA) or ethyl bromodifluoroacetate (EBDFA). These reactions could be carried out at room temperature in good to excellent chemical yields. Both stepwise and one-pot procedures have been developed, which makes this strategy more attractive.