Crystal structure and spectroscopy properties of new PtII complexes containing 5-alkyl-1,3,4-oxadiazol-2-thione derivatives

Abstract

This work describes the synthesis and total characterization of five novel PtII complexes of the type trans-[Pt(L)2(PPh3)2] (L = 5-alkyl-1,3,4-oxadiazol-2-thione derivatives and PPh3 = triphenylphosphine). These PtII complexes were characterized by elemental analysis, conductivity measurements, mass spectrometry, FT-IR, multinuclear NMR spectroscopy and X-ray diffraction crystallography. According to X-ray diffraction data, all complexes exhibited distorted square-planar geometry, in which two 5-alkyl-1,3,4-oxadiazol-2-thione derivatives coordinate a platinum ion through the sulfur atom with two triphenylphosphine molecules completing the coordination sphere. The isomerization of the platinum complexes was also investigated in deuterated chloroform solution by 31P{1H} and 195Pt{1H} NMR spectroscopy. In all cases, the trans-isomer was found according to the observed coupling constants (J).