Flavin Metallaphotoredox Catalysis: Synergistic Synthesis in Water

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright © 2022 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acscatal.2c00773.Combining a transition metal with a photocatalyst can drive modern synthetic chemistry. For transformations performed in water, this concept has been largely unexplored. We report the successful merger of a biocompatible flavin photocatalyst with a palladium catalyst to build isotopically enriched peptidomimetics, to mediate conjugate addition and C–H functionalization reactions, and to assemble unprotected proteinogenic and nonproteinogenic peptides, in water. We detail the important role of the ligand and the palladium oxidation state for controlling product selectivity when constructing synthetic peptides