Studies of the Mixed Chromium(III) Complexes Containing Ethylenediamine-N,N′-diacetic Acid

Abstract

Three new mixed chromium (III) complexes containing ethylenediamine-N,N′-diacetic acid (EDDA) and amino acid, [Cr(edda)(L)] (L= anion of glycine, α-alanine and β-alanine), were prepared from [Cr2(OH)2(edda)2]·6H2O. On the basis of their chemical analyses and the visible and infrared absorption spectra, the geometrical structure of the three mixed ligand complexes was estimated to be the facial form with respect to the coordinated three nitrogen atoms, where the configuration of the coordinated edda was inferred to take the β-form (cis with respect to the coordinated oxygen atoms of edda). The new mixed ligand complex containing the glycine anion, [Cr(ox)(gly)(en)]·H2O, was also prepared from cis-[Cr(ox)(H2O)2(en)]Br, and its geometry was discussed in the connection with its visible absorption spectrum.