Optical Resolution and Ternary System Solubility Isotherms of Cobalt(III) Complex Salts

Abstract
The characteristics of three-component phase diagrams consisting of water and a pair of enantiomeric or diastereomeric cobalt(III) complex salts have been clarified experimentally by constructing the solubility isotherms of the following 6 ternary systems at 25 °C: H2O–Δ-[Co(ox)(en)2]X–Λ-[Co(ox)(en)2]X, where X stands for Cl−, I−, (R,R)-C4H5O6–, Δ-[Co(edta)]−, 1/2[Sb2{(R,R)-C4H2O6}2]2− or d-C10H14OBrSO3−. It has been found that the latter two anions form an active racemate, rac-[Co(ox)(en)2]2[Sb2{(R,R)-C4H2O6}2]·5H2O and rao[Co(ox)(en)2](d-C10H14OBrSO3)·H2O, respectively. Solubility of the [Co(ox)(en)2]+ salts containing optically active counterions was determined at 5–60 °C in water.