Dual Metallaphotoredox‐Catalyzed Directed C(sp2)−H Functionalization: Access to C−C/C‐Heteroatom Bonds

Metallaphotoredox catalysis represents the combination of two activation modes: metal‐catalyzed C−H functionalization and visible‐light‐induced photocatalysis. This appealing dual catalysis technique has evolved as a versatile platform that has paved the way for diverse low‐energy pathways for a plethora of synthetic transformations. The synergistic combination of two “green” approaches has garnered enormous interest owing to the development of sustainable strategies. In the recent past, significant advancements have been accomplished in constructing site‐selective C−C and C‐heteroatom bonds. This review outlines the use of photoredox catalysis in directing group‐assisted C−H functionalization reactions. The mechanistic insights of the developments and synthetic applications are addressed. This review outlines a handful of transformations employing transition‐metal and photoredox catalysis by auxiliary‐assisted C−H activation strategy to assemble synthetic libraries of C−C and C‐heteroatom bonds. The review also features the substrate scope and mechanistic insights of the key methodologies.