Synthesis and structural investigation on tridentate ligands possessing oxygen and nitrogen donor atoms

Abstract

The dissociation constants of o-(N-furan-2-acetylimino) benzoic acid (HFB) and o-(N-pyrrolr-2.methylimmo) benzoic acid (H1.PB) and the stability constants, and thermodynamlc parameters of their chelates with La (III). Ce(JII). Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Ho(III) and Er(III) have been determined by Calvin-Bjerrum pH-titration technique as modified by Irving and Rassotti. The stability constants of the metal chelates increase with decreasing ionic size of the Ln (III) ions. Solid Ln (lIT) chelates are characterised by molecular mass measurements, elememntal analyses, magnetic moment, conductance, IH nmr, electronic and if spectral data.