A dicationic distibine stabilized by intramolecular π-π interaction and second-sphere coordination

Abstract

A new type of pincer ligand (1) featuring an Sb(I) center and two pendent amine arms has been developed. The single electron oxidation of 1 produces a dicationic distibine (2). Crystallographic and computational investigations indicate that 2 gains stabilization from intramolecular π-π interaction and second-sphere coordination. The reactions of 2 with a disulfide and Co₂(CO)₈ reveal its dual redox reactivity associated with the oxidation of the Sb−Sb bond and the reduction of the cationic Sb(II) centers.