Lighting the way to chirality: a review of asymmetric transition metal catalysis in photoexcited states

In recent years, photoinduced transition metal (TM) catalysis has garnered significant attention for advancing various asymmetric chemical transformations. Unlike traditional photocatalysis, photoexcited TM catalysis operates through outer-sphere mechanisms, leveraging direct and strong substrate-metal interactions. The TM complex performs a dual role, both harvesting light and catalyzing chemical transformations, typically via single electron transfer pathways. This innovative approach establishes a multifunctional platform that facilitates the development of novel, particularly enantioselective, chemical transformations. Given that photoexcited TM asymmetric catalysis serves as an important complement to ground-state TM asymmetric catalysis, this review highlights recent advancements in photoexcited TM (Cu, Pd, Ir, Ti, etc.) asymmetric catalysis.