Unprecedented N-inserted disulfide ligand stabilized by coordination to the electropositive Co^III center

The reaction of Co^II and 2,2′-dipyridyldisulfide (PySSPy) in the presence of azide produced a peculiar monomeric complex [Co ^III(PyS)(PyS-N-SPy)(N₃)] (1). In this reaction, redox chemistry takes place, which is associated mainly with the oxidation of Co ^II to Co^III and the reduction of PySSPy. During the reaction, the azide ion decomposes and donates a nitrogen atom to PySSPy. The crystal structure of 1 provides evidence that the unusual, N-inserted ligand PyS-N-SPy can be stabilized through coordination to the electropositive Co ^III ion.