Dinuclear oxidative addition reactions using an isostructural series of Ni2, Co2, and Fe2 complexes

A family of low-valent Ni-2, Co-2, and Fe-2 naphthyridine-diimine (NDI) complexes is presented. Ligand-based pi* orbitals are sufficiently low-lying to fall within the metal 3d manifold, resulting in electronic structures that are highly delocalized across the conjugated [NDI]M-2 system. This feature confers stability to metalmetal interactions during two-electron redox reactions, as demonstrated in a prototypical oxidative addition of allyl chloride.