Synthesis and characterization of [Me 2NC(S)NP(S)(O iPr) 2] − complexes of Co(II), Ni(II), Zn(II) and Cd(II)

Abstract

Reaction of the potassium salt of N-thiophosphorylthiourea Me 2NC(S)NHP(S)(O iPr) 2 ( HL) with Co(II), Ni(II), Zn(II) and Cd(II) cations in aqueous EtOH leads to M(L- S, S′) 2 ( ML 2 ) chelate complexes. The structures of the resulting compounds were studied by IR, UV–Vis, 1H, 31P{ 1H} NMR spectroscopy and microanalysis. The metal center is found in a tetrahedral environment in complexes CoL 2 , ZnL 2 , CdL 2 and square-planar in NiL 2 formed by the C S and P S sulfur atoms of two deprotonated ligands L. According to the NMR and UV–Vis spectroscopy data it was established that the metal cation of NiL 2 is in a square-planar environment in CH 2Cl 2, CHCl 3 and C 6H 6, whereas NiL 2 shows features of tetrahedral or octahedral complexes in acetone, DMSO and DMF. Molecular structures of complexes were elucidated by single crystal X-ray diffraction analysis.