Synthesis, spectroscopic characterization and biological activities of Sm(III) and Dy(III) complexes with Schiff base derived from 2-hydroxy-1-naphthaldehyde and 2-aminobenzoic acid

Abstract

A tridendatate Schiff base,L, 2-((2-hydroxynaphthalen-1-yl) methyleneamino)benzoic acid was prepared by condensation of 2-aminobenzoic acid with 2-hydroxy-1-naphthaldehyde.The prepared ligand was used to synthesize Sm(III) and Dy(III) complexes [LnL(NO₃)₂]NO₃.2H₂O, (Ln=Sm(III) and Dy(III)).The ligand and its lanthanide (III) complexes were characterized by elemental analysis, molar conductivity, thermal analysis and IR spectroscopy.The elemental and spectral analysis show that ligand coordinate to the central lanthanide(III)ion by its imine nitrogen, phenolic oxygen and carboxylic oxygen in 1:1 stoichemetry. The complexes were found to be electrolytic in nature on basis of their molar conductance values. The thermal analysis data provided an evidence for the present of uncoordinated water in all complexes. It was found that the complexes exhibit higher antioxidant activity than that of its corresponding ligand.

Keywords: Complex, ligand, Schiff base, spectroscopy