A series of ligands of quinoline azodye derivatives (HLI–HLVI) have been prepared and characterized by elemental
analysis, X-ray diffraction analysis, 1H NMR and IR spectra. The proton–ligand dissociation constant of the ligands
(HLI–HLVI) and the metal stability constant of their Mn2+, Co2+, Ni2+, Cu2+, La3+, UO2
2+ and Th4+ complexes
have been determined potentiometrically in 1 M KC1 and 40% (V:V) EtOH–water mixture