Synthesis, structural characterization and spectroscopic properties of [Pt(bddn)]Cl₂·3.5H₂O (bddn = 1,9-bis(3,5-dimethyl- 1-pyrazolyl)-3,7-dithianonane)

The reaction of the potentially tetradentate ligand 1,9-bis(3,5-dimethyl-1- pyrazolyl)-3,7-dithianonane (bddn) with [PtCl2(CH3CN) 2] yields a mixture of complexes, where the ligand acts as bidentate SS, or tetradentate 2NS or NSSN. This mixture of complexes SS, 2NS, and NSSN was crystallized with dichloromethane/n-pentane (1:1) and crystals of [Pt(bddn)]Cl2 (isomer NSSN) were obtained. The complex has been characterized by elemental analyses, mass spectrometry, conductivity, IR, 1H, 13C{1H}, 1H{195Pt}, 195Pt{1H}NMR, HSQC and NOESY spectroscopies, and X-ray diffraction. Compound [PtCl2(bddn)] • 3.5H2O crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 15.430(7) Å, b = 17.405(4) Å, c = 18.887(7) Å, β = 91.24(2)°, V = 5071(3) Å3, Z = 4, R 1 = 0.0354, wR2 = 0.1034. This compound consist of discrete cations [Pt(bddn)]2+, Cl- anions and water molecules of crystallization. The platinum(II) is tetracoordinated by two azine nitrogen atoms and two sulfur atoms of the thioether-pyrazole ligand, in a distorted square planar geometry. © 2007 Springer Science+Business Media, LLC.