Reversible metal-centered reduction empowers a Ni-Corrin to mimic F430

This communication presents a novel truncated Ni^II-containing metbalamin and describes its reversible one electron reduction to a catalytically active Ni^I species, that features cofactor F430 model character. Our results strikingly demonstrate that stabilization of Ni^I is not restricted to the related hydroporhyrinoid ligands and is of relevance to the application of metallocorrins in (biomimetic) catalysis.