Redox-Induced Change in the Ligand Coordination Mode

The reaction of cobalt­(II) pivalate with a spin-labeled Schiff base (HL¹) in organic solvents formed trinuclear complex [Co₃(Piv)₂L¹₂L²₂]·Solv (Solv is Me₂CO and/or C₇H₁₆ and CH₃CN) containing both nitroxide L¹ and the product of its single-electron reduction, nitrone L². The formation of [Co₃(Piv)₂L¹₂L²₂] was a consequence of an unusual phenomenon, which we called “redox-induced change in the ligand coordination mode”. A reduction of L¹ to L² led to a change in the set of donor atoms and even in the size of the metallocycle. This phenomenon was also found for mononuclear [CrL¹₂L²] and [FeL¹₂L²]·Me₂CO