Synthesis and characterization of lanthanide complexes of 1-phenyl-3-methyl-5- hydroxy-4-pyrazolyl-phenyl ketone-2ʹ-picolinoyl hydrazone

Abstract

The  ligand, 1-phenyl-3-methyl-5-hydroxy-4-pyrazolyl-phenyl ketone-2ʹ-picolinoyl hydrazone (HL) is prepared by condensation of 1-phenyl-3-methyl -4-ben zoyl-5-pyrazolone with 2-picolinic acid hydrazide. Seven complexes of lanthanides with HL of the type [Ln (HL)₃].2 H₂O (where Ln=trivalent lanthanides such as La, Ce, Nd, Sm, Gd, Dy and Er) have been synthesized and

characterized by complexometric titration of lanthanoid ions,elemental analysis, molar condudance, IR, ¹H NMR, electronic spectral studies, and TGA analysis, IR spectra and thermogram shows the presence of two water moieties outside the coordination sphere and are non-electrolytic in nature. The complexes appear to be nine -coordinated and ligand act as a tridentate ligand.