Synthesis, Characterization And Properties Of Rare Earth With O-Carboxybenzaldehyde Salicyloylhydrazone Binary And Ternary Complexes

Based on the biological significance and applications of mixed ligand complexes formed by the rare earth elements, aroylhydrazone and glycine, this paper mainly concluded the following work:A new ligand o-carboxybenzaldehyde salicyloylhydrazone was synthesized in benzene; and the optimization conditions of synthesis were got. The composition and structure of the ligand were determined by elemental analysis, IR, UV, NMR, MS and X-ray diffraction. Thirteen binary complexes had been synthesized by the reaction of o-carboxybenzaldehyde salicyloylhydrazone with rare earth nitrate (RE = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb and Y, n=2~3). The composition RE(C15H11N2O4)(C15H10N2O4)·nH2O was determined by elemental analysis, molar conductivity and chemical analysis, and the structure was characterized by molar conductivity, IR, UV-Vis, FS, NMR and X-ray powder diffraction.Eight ternary complexes of rare earth ions (RE=La, Ce, Pr, Nd, Sm, Eu, Gd and Tb) with o-carboxybenzaldehyde salicyloylhydrazone and glycine were synthesisd. The composition and structure were analyzed through elemental analysis, molar conductance, IR, UV-Vis and X-ray powder diffraction.The thermal decomposition of the ligand, binary complexes and ternary complexes were carried out by TG-DTG analysis at 5, 10 and 15 K·min-1, respectively. The Kissinger method was used to calculate the apparent activation energies and kinetics parameters of the thermal decomposition stages of the ligand and the complexes. The results showed that binary complexes and ternary complexes had higher thermal decomposition temperature; and their thermal stability was higher than the ligand. The binary complexes of La, Yb nitrate with the o-carboxybenzaldehyde salicyloylhydrazone were chosen to investigation their bioactivity to staphylococcus aureus by using the method of the mininal inhibitory concentration. The results showed that the o-carboxybenzaldehyde salicyloylhydrazone and the binary complexes possess better antibacterial effect. The antibacteria experiment of La nitrate with the o-carboxybenzaldehyde salicyloylhydrazone to staphylococcus aureus has also been done. It is shown that the antibacterial activity of the La binary complex is better than the o-carboxybenzaldehyde salicyloylhydrazone.