A seven membered chelate ring complex of Mn(II) derived from bis(5-phenyl-2H-1,2,4-triazole)-3-yl-disulfane and cleavage of the S–S bond in a Co(II) complex: Synthesis, spectral and structural characterization

The reaction of Mn(OAc)2·4H2O with bis(5-phenyl-2H-1,2,4-triazole)-3-yl-disulfane (H2ptds·2H2O) (1) yielded new complex [Mn(ptds)(o-phen)2] (2). It is observed that under similar conditions the reaction of Co(OAc)2 with H2ptds·2H2O (1) leads to thermolysis of the S–S bond of the disulfane to yield [Co(pts)(o-phen)2]·H2O·0.5C2H5OH, with the newly generated organic ligand 5-phenyl-2H-1,2,4-triazole-3-sulfinate, (pts)2−. The ligand H2ptds·2H2O (1), [Mn(ptds)(o-phen)2] (2) and [Co(pts)(o-phen)2]·H2O·0.5C2H5OH (3) crystallized into monoclinic, trigonal and triclinic crystal systems, respectively. The triazole ring nitrogen of the bidentate ligand chelates the Mn(II) center forming a seven membered chelate ring, while N, O donor sites of the resulting triazole sulfinate bond Co(II) to form a five membered chelate. The resulting complexes are paramagnetic and have a distorted octahedral geometry.

The new complexes [Mn(ptds)(o-phen)2] (2) and [Co(pts)(o-phen)2]·2H2O·C2H5OH (3) with bis(5-phenyl-2H-1,2,4-triazole)-3-yl-disulfane (H2ptds·2H2O) (1)) have been synthesized, containing o-phenanthroline as a coligand. The triazole ring nitrogen of the bidentate ligand chelates the Mn(II) center forming a seven membered chelate ring, while N, O donor sites of the resulting triazole sulfinate bond to Co(II) forming a five membered ring structure. The resulting complexes are paramagnetic and have a distorted octahedral geometry.Figure optionsDownload as PowerPoint slideHighlights
► [Mn(ptds)(o-phen)2] and [Co(pts)(o-phen)2]·H2O·0.5C2H5OH have been synthesized. The triazole N of disulfane chelates the Mn(II) center forming a seven membered chelate ring.
► Co(II) cleaves the S–S bond of disulfane and oxidize it to a sulfinate which is bonded to the Co(II) centre.
► The resulting complexes are paramagnetic and have a distorted octahedral geometry.