Leveraging Electron- and Proton-Storing Ligands for Selective Ni- and Cu-Catalyzed Redox Transformations

Metal-ligand cooperativity, or the active participation of both the metal and ligand in chemical transformations, is one powerful strategy from biology that can be mimicked in synthetic chemistry. For example, redox-active ligands allow for multi-electron reactions using metals that typically engage in single-electron processes. What’s more, proton-shuttling moieties on the ligand scaffold can enable fine-tuned control over the transfer of proton, H-atom, or hydride equivalents in addition to providing hydrogen bonding interactions to position a substrate or stabilize an intermediate. Combining multiple metal-ligand cooperative strategies in a single ligand has been shown to be an effective approach in widely utilized reactions such as the hydrogenation of unsaturated groups. Within this field, a 2,5-dihydrazonopyrrole (DHP) scaffold has been demonstrated to store and transfer a full equivalent of H2 from the ligand backbone. This thesis focuses on DHP complexes of Ni and Cu and the development of catalytic redox methods utilizing the cooperative properties of these complexes.