Binary Complexes of Zirconium(IV) Naphthylideneamino Acids and their Ternary Complexes with Some Imidazoles. Synthesis, Characterization, and Electrochemical Studies

Abstract A new series of binary and ternary complexes of zirconium(IV) with N‐naphthylideneamino acids and some imidazoles has been synthesized. The complexes were characterized on the basis of elemental analyses, 1H NMR, IR and electronic spectra, conductivity, and thermal analytical data. It was found that N‐naphthylideneamino acids act as divalent tridentate (ONO) Schiff bases, whereas the imidazoles behave as monodentate ligands. The involvement of anions (OAc− and Cl−) in coordination was explored. The apparent formation constant values of Zr(IV)–Schiff base binary complexes were determined by a continous‐variation spectrophotometric method. Voltammetric results indicate that some of the prepared complexes underwent two successive, irreversible and reversible one‐electron charge transfer steps coupled with a follow‐up chemical reaction. The stability and redox properties of complexes are discussed in relation to the ligand molecular structure.