TELLURIUM(II)-THIOSEMICARBAZONE COMPLEXES‐A PARALLEL TO THE LIGATION OF THIOUREAS

Abstract The tellurium(II)-complexes of the type Te(XTSC)2Cl2 (I) and Te(XTSC)4Cl2 (II), where XTSC=benzaldehyde, acetophenone, salicylaldehyde or 2-hydroxyacetophenone thiosemicarbazone have been isolated. The IR, PMR and CMR spectra of the complexes in conjunction with their elemental analyses and conductance measurements, indicate the formation of a three centre-four electron bond between tellurium and two sulphur atoms of the thiosemicarbazones, trans to each other. These results exhibit for the first time that thiosemicarbazones may ligate with tellurium(II) in a manner parallel to that of thioureas. The square planar and octahedral arrangement of the ligands around tellurium are proposed for I and II type complexes respectively.