Transition metal complexes with thiosemicarbazide-based ligands. Part 58. Synthesis, spectral and structural characterization of dioxovanadium(V) complexes with salicylaldehyde thiosemicarbazone

Abstract

The first two complexes of dioxovanadium(V) with salicylaldehyde thiosemicarbazone (SALTSC), of the coordination formulas [VO2(SALTSC- -H)] H2O (1) and NH4[VO2(SALTSC-2H] (2), were synthesized and characterized by elemental analysis, conductometric measurements, IR and UV-Vis spectroscopy and X-ray analysis. The complexes were obtained in the reaction of an aqueous ammoniacal solution of NH4VO3 and SALTSC. The results of the characterization showed that SALTSC was coordinated in the usual ONS tridentate mode as monoanion in complex 1 and dianion in complex 2. In both complexes, the vanadium atom is in a deformed square-pyramidal environment and is slightly shifted towards the apical oxo-ligand (? 0.52 Å).