ChemInform Abstract: Complexes of Aminophosphonates. Part 1. Transition Metal Complexes of Aminophosphonic Acid Analogues of α‐Alanine. β‐Alanine, Phenylalanine and Tyrosine.

Abstract

ChemInform Abstract The stoichiometries and stability constants of the proton, Co(II), Ni(II), Cu(II), and Zn(II) complexes of the title phosphonic acids (I) and (II) are determined pH-metrically. From these data and the spectral parameters of the complexes it is established that these simple acids coordinate similarly to aminocarboxylic acids forming 1:1 and 1:2 chelate complexes. However, a species with only phosphonate group coordination also exist at low pH. The differences between the complex-forming properties of aminophosphonates and aminocarboxylates are explained by the difference in basicity, charge and size of the -PO32-and -COO-groups.