12 Hypervalent Iodine Reagents in Photochemistry

Abstract Harnessing their unique three-center, four-electron bonding motif, hypervalent iodine compounds have emerged as powerful and versatile reagents in modern organic synthesis, with particularly significant applications in photochemical transformations. This review provides a systematic overview of recent advances that exploit these reagents in diverse photoredox roles, including direct photoexcitation, and their use as radical precursors, radical acceptors, hydrogen-atom-transfer (HAT) reagents, and redox-active agents. Furthermore, it explores their capacity to mimic transition-metal behavior through distinct covalent and non-covalent activation modes. By consolidating these multifaceted reactivities, the integral role of hypervalent iodine reagents in advancing the frontier of sustainable photochemical synthesis is underscored.