SYNTHESIS AND CHARACTERIZATION OF Zn(H) COMPLEXES WITH SOME ACYLHYDRAZINE SCHIFF BASES

Three acylhydrazine derived Schiff bases and their Zn(II) complexes have been prepared and characterized on the basis of elemental analyses, molar conductances and spectroscopic (electronic, IR, 'H NMR and 13 C NMR) data.All these Schiff bases function as tridentate ligands and the deprotonated enolic form is the preferred tautomer in the coordination of the metal ions. EXPERIMENTAL Material and MethodsAll chemicals and solvents used were of Analar grade.Zn(II) chloride has been used in the syntheses.2-Pyrrolcarboxaldehyde, benzoylhydrazine, nicotinoylhydrazine and salicyloylhydrazine were obtained from Merck.IR spectra were obtained as KBr discs on a Philips Analytical PU 9800 FTIR spectrophotometer.*H NMR and 13 C NMR spectra were recorded on a Bruker 250 MHz spectrometer in DMSO-<4• UV-Visible spectra were obtained in DMF on a Hitachi U-2000 double-beam spectrophotometer.C, Η and Ν analyses were carried out by Butterworth Laboratories Ltd. Conductances of the metal complexes were determined in DMF on a Hitachi YSI-32 model conductometer.Magnetic measurements were done on the solid complexes using the Gouy method.Melting points were recorded on a Gallenkamp apparatus and are uncorrected.