Synthesis and kinetic stability of dysprosium(III), europium(III), and neodymium(III) complexes with tetraazaporphine in acetic acid solutions

Previously unknown dysprosium(III), europium(III), and neodymium(III) compl exes with tetraazaporphine were synthesized from the ligand and the corresp onding metal acetylacetonates. The kinetic stability of the complexes in aq ueous and methanolic solutions of acetic acid was studied. It was shown tha t the complexes in these media undergo solvoprotolytic dissociation with re lease of the tetraazaporphine ligand. The kinetic parameters of the dissoci ation were determined, and the reaction mechanism was discussed. The comple xes were ranked with respect to their kinetic stability.