About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Paper
Synthesis and complexation properties of a new tetraazatricarboxylate ligand
Abstract
A non-cyclic tetraazatricarboxylate ligand, tris(4-carboxy-3-methyl-3-azabutyl)amine (H3L), derived from tris(2-aminoethyl)amine, was synthesised and purified. Its macroscopic and microscopic protonation behaviour was studied using potentiometry and proton NMR titrations, respectively. Stability constants for its complexes with Ni2+, Cu2+, Zn2+, Cd2+ and Gd3+ were obtained potentiometrically and compared with those of related ligands. The structure, protonation and dynamics of the complexes of H3L with Zn2+ and La3+ were investigated by proton NMR spectroscopy as a function of pH and the results were in accord with the potentiometric data for the complexes of Zn2+ and Gd3+. A nuclear magnetic relaxation dispersion study compared the water-proton relaxation parameters of [GdL] and [Gd(dtpa)]2- (H5dtpa = N,N,N′,N″,N″-diethylenetriaminepentaacetic acid), concluding that their water co-ordination numbers are the same but the former complex has a shorter electron-spin relaxation time.