Organic Reactions Enabled by Catalytically Active Metal–Metal Bonds

Abstract

Molecular transition-metal catalysts are predominantly Werner-type coordination complexes, wherein a single metal ion surrounded by ligands functions as the sole locus of reactivity. A major focus of organometallic chemistry has been to understand how supporting ligands can be rationally modified in order to access more active and selective catalysts. Since the 1960s, however, it has been recognized that metals can also form direct metal-to-metal bonds, giving rise to an extraordinary diversity of multinuclear assemblies. If metal–metal bonding could be harnessed productively in catalysis, it would provide access to a large parameter space that is not available through ligand modification. This review highlights recent examples of organic transformations that were discovered using catalysts containing metal–metal bonds.