STOICHIOMETRIC, KINETIC, AND MECHANISTIC INVESTIGATIONS OF THE REACTIONS OF O-BONDED (ETHYLENEDIAMINE-N,N,N',N'-TETRAACETATO)PENTAAMMINECOBALT(III) COMPLEX AND ITS RELATED COMPLEXES WITH HEXAAQUACHROMIUM(II) IONS

The products of the reactions of [Co(Hnedta)(NH3)5](n-1)+, [(NH3)5Co{edtaCr(H2O)}]2+, [(NH3)5Co{edtaCo(H2O)}]2+, and [Co(edta)]- with [Cr(H2O)6]2+ in acid solutions were separated with the aid of SP-Sephadex column chromatography and identified from the chromatographic behavior, visible absorption spectra, and chemical analyses of chromium and/or cobalt ions. Three chromium(III) complexes were newly characterized as the reaction products: [(H2O)5Cr{edtaCr(H2O)}]2+, [(NH3)5Co(Hnedta)Cr(H2O)5](n+2)+, and [Cr(Hnedta)(H2O)5](n-1)+. From the determination of the quantitative product distribution, stoichiometry of the reactions was established. Then, kinetic measurements were made for these reactions. On the basis of these results, the mechanisms of the reactions are discussed. © 1979, American Chemical Society. All rights reserved.