Association Involving Optically Active Ions. I. Association Constants of Tris(ethylenediamine)cobalt(III) and Tartrate Ions

• Published in: Bulletin of the Chemical Society of Japan Vol. 40; no. 4; pp. 826 - 829
• Main Authors: Ogino, Kazuko, Saito, Umihiko
• Format: Journal Article
• Language: English
• Published: Tokyo Chemical Society of Japan 01.01.1967
• ISSN: 0009-2673; 1348-0634
• DOI: 10.1246/bcsj.40.826

Abstract The enantiomer differentiation of an optically active metal complex through the presence of another kind of optically active ion in the solution is considered to be due to association. A mathematical treatment has been made of the equilibria which exist in solutions containing either or both antipodes of an optically active ion and optically active counter ions which do not racemize rapidly. The results have been applied to a system of [Co en3]3+ (en=ethylenediamine) and d-tartrate ions. The increase in the optical absorbancy of [Co en3]3+ in the charge transfer absorption region is not the same for d-, l- and dl-[Co en3]3+. The association constants of d-[Co en3]3+·d-tartrate2− and l-[Co en3]3+·d-tartrate2 were found, by an analysis of the increase in the optical absorbancy, to be 26 and 21 respectively at μ=0.1 at 25°C.