TERNARY COMPLEXES OF N-(2-ACETAMIDO)IMINODIACETIC ACID AND SOME AROMATIC-ACIDS - ISOLATION AND STABILITY-CONSTANTS IN SOLUTION

Ternary 1:1:1 complexes of Y-III, Co-II, Ni-II, Cu-II, La-III, Ce-III and UO22+ with N-(2-acetamido)iminodiacetic acid (H(2)ADA) as primary ligand and salicylic, anthranilic or phthalic acid as secondary ligand are described. The complexes of Co-II and Cu-II were isolated and cha racterized by microanalysis, molar conductance measurements, thermal a nalysis, i.r. and u.v.-vis. spectra. The formation constants of the 1: 1:1 ternary complexes were determined potentiometrically in 20% (w/w) EtOH-H2O at 24 degrees C. The stabilities of the 1:1:1 M(n+):ADA(2-):a romatic acid ternary complexes are higher than those of the correspond ing 1:1 M(n+):aromatic acid binary complexes.