Cobalt in a Bis-β-diketiminate Environment

The reaction of Co2(mesityl)4 with acetonitrile leads to the formation of a planar, low spin, bis-β-diketiminate cobalt­(II) complex, (1-mesitylbutane-1,3-diimine)2Co (1). EPR spectroscopy, magnetic studies, and DFT calculations reveal the Co­(II) ion to reside in a tetragonal ligand field with a 2B2(dyz)1 ground state electronic configuration. Oxidation of 1 with ferrocenium hexafluorophosphate furnishes (1-mesitylbutane-1,3-diimine)2Co­(THF)2PF6 (2). The absence of significant changes in the metal–ligand bond metrics of the X-ray crystal structures of 1 and 2 supports ligand participation in the oxidation event. Moreover, no significant changes in C–C or C–N bond lengths are observed by X-ray crystallography upon oxidation of a β-diketiminate ligand, in contrast to typical redox noninnocent ligand platforms.