Synthesis and Characterization of Cobalt Complexes with Radical Anionic α‑Diimine Ligands

Three cobalt complexes, [LCo­(μ-Cl)]2·THF·Et2O (1), [LCo­(η6-toluene)] (2), and [LCo]2 (3), where L = [(2,6-iPr2C6H3)­NC­(Me)]2, have been synthesized from reduction of the dichloro cobalt precursor [LCoCl2] by sodium or potassium metal. Single-crystal X-ray diffraction analyses reveal that the complexes display novel structures with the singly reduced form (L•–) of the α-diimine ligand: the dichloro-bridged binuclear complex 1, the mononuclear 2 with an η6-coordinated toluene molecule, and the dimer 3 through Co–aryl interactions of two [LCo] units. The compounds were further characterized by EPR and magnetic studies.