Triggering Redox Activity in a Thiophene Compound: Radical Stabilization and Coordination Chemistry.

The synthesis, metalation, and redox properties of an acyclic bis(iminothienyl)methene L- are presented. This π-conjugated anion displayed pronounced redox activity, undergoing facile one-electron oxidation to the acyclic, metal-free, neutral radical L. on reaction with FeBr2 . In contrast, the reaction of L- with CuI formed the unique, neutral Cu2 I2 (L. ) complex of a ligand-centered radical, whereas reaction with the stronger oxidant AgBF4 formed the metal-free radical dication L.2+ .