Polarographic studies on mixed ligand complexes involving amino acids : ternary systems, Cd-α-alanine-oxalate and Cd-β-alanine-oxalate

Ternary complexes of cadmium(II) with oxalate as primary ligand and α- and β-alanines as secondary ligands have been studied polarographically. Formation of three mixed complex species, [Cd(amino acid) (oxalate)], [Cd(amino acid) (oxalate)2] and [Cd(anino acid)2(oxalate)], is observed in each case. The reduction is reversible and diffusion-controlled. The stability constants have been evaluated usino the method of McMasters. The α-alanine complexes are found to be more stable than the corresponding β-alanine complexes. (author)