Electrophotoredox/cerium-catalyzed unactivated alkanes activation for the sustainable synthesis of alkylated benzimidazo-fused isoquinolinones

The external oxidant-free exploitation of abundant alkane feedstocks as alkyl radical precursors remains a topic of high interest in synthetic communities. Here, we report a Ce-catalyzed electrophotoredox radical addition/cyclization cascade for the incorporation of unactivated alkanes to produce alkylated benzimidazo-fused isoquinolinones and other N-containing polycycles. Compared with previous works employing prefunctionalized alkyl radical precursors, this electrophotocatalytic protocol features high step-economy. The external oxidant-free conditions accompanied by the generation of H2 as the only byproduct further highlight the high redox- and atom-economy of this catalytic protocol.