NEW NICKEL(II), COPPER(II), PLATINUM(II) AND PALLADIUM(II) COMPLEXES OF A MULTIDENTATE SULFUR-NITROGEN CHELATING AGENT

A new, potentially polydentate sulfur-nitrogen chelating agent, 2,6-bi s(N-methyl-S-methyldithiocarbazato)pyridine (L) has been synthesized a nd characterized. With nickel(II) salts, the ligand yields complexes o f empirical formula NiLX2 . nH(2)O (X = Cl-, NCS- or NO3-; n = 0 or 1) in which it behaves as a quadridentate NSSN chelating agent, coordina ting to the nickel(II) ion via the two amino nitrogen atoms and the tw o sulfur atoms. Magnetic and spectral evidence support a distorted oct ahedral structure for these complexes. The ligand reacts with copper(I I), platinum(II) and palladium-(II) salts to yield homo-binuclear comp lexes of general formula [M2LX4]. nSol (M = Cu-II, Pt-II or Pd-II; X = Cl- or Br-; n = 0.5, 1 or 2; Sol = H2O, MeOH or MeCOMe), in which eac h of the metal ions is in a square-planar environment. These complexes have been characterized by a variety of physicochemical techniques.