New complexes of an unsymmetrical tetradentate isothiosemicarbazone: Structural, spectral and thermogravimetric investigations, and their nanoparticles synthesis

The new Schiff base ligand 2-hydroxyacetophenone S-ethylisothiosemicarbazone hydroiodide (H2L·HI) has been synthesized. In addition, the complexes with the general formulae [Ni(N2O2], [Cu(N2O2] and [VO(N2O2], where N2O2 means S-ethyl-N1-(2-hydroxyacetophenone)-N4-(salicylidene) isothiosemicarbazide, have been prepared by the reaction of H2L·HI and salicylaldehyde with metal ions of nickel(II), copper(II) and vanadium(IV). All of the compounds have been characterized by elemental analysis, FT-IR, 1H NMR, UV–Vis, thermogravimetry, conductivity measurements and X-ray crystallography. The obtained data showed that the template reactions were performed successfully. H2L·HI crystallized in the Z configuration, since the N3 and N1 atoms are in trans positions with respect to each other. The geometries of the nickel(II) and copper(II) complexes were determined as slightly distorted square-planar, while the vanadium(IV) complex adopted a distorted square-pyramidal structure. The nanoparticles of NiO, CuO and V2O5, with average particle sizes of 27, 22 and 39 nm, were also synthesized purely by the direct thermal decomposition method from the complexes as new precursors. The nanoparticles were characterized by XRD diffraction.

Four new compounds of an isothiosemicarbazone are synthesized. Structural, spectral and thermogravimetric studies are performed, showing H2L crystallizes as the Z isomer, while the complexes show distorted square-planar and square-pyramidal geometries. Nanoparticles of NiO, CuO and V2O5 are also synthesized.Figure optionsDownload as PowerPoint slide