Synthesis and characterization of metal complexes of cobalt(II), nickel(II), copper(II), and silver(I) with syn‐thiophene‐2‐aldoxime

Abstract

Complexes of syn‐thiophene‐2‐aldoxime (TDH) have been synthesised and characterized on the basis of elemental analysis, molecular weight, conductance, magnetic susceptibility and i. r. spectra. These are [Co(TDH)4Cl2], [Co(TD)2], [Ni(TDH)4Cl2], [Ni(TD)2(TDH)], [Cu(CH3COO)2(TDH)]2, [Cu(TD)(OH)]2 and AgNO3 · 2TDH. In these complexes the ligand (TDH) functions as monodentate (coordinating through nitrogen atom) or bidentate (coordinating through the nitrogen and sulphur atoms). The CS stretching frequency (of the thiophene ring) at 718 cm−1 may be taken as the criteria for the denticity of this ligand. A shift to lower frequency is observed in the complex if the ligand acts as a bidentate. However, this band is not affected if the ligand acts as monodentate.