Analytical Sciences

Abstract − Analytical Sciences, 16(2), 131 (2000).

Reversal Behaviors of the Enantiomer Migration Order andthe Stereo-selectivity of Cu(II) Complex with Amino AcidEnantiomers in Ligand Exchange-Micellar ElectrokineticChromatography
Zilin CHEN, Jinming LIN, Katsumi UCHIYAMA, and Toshiyuki HOBO
Department of Applied Chemistry, Graduate School of Engineering, Tokyo Metropolitan University,Minami-Ohsawa, Hachioji, Tokyo 192-0397, Japan
The dependence of the enantioselectivity and enantiomer migration order (EMO) on the chirality and stereo-conformationof ligands used for the chiral selectors of Cu(II) complexes was investigated. It was interestingly observed that EMOswere reversed not only by a change of the ligand chirality of selector, but also by the trans- or cis-conformation of a 4-hydroxy substituent in 4-hydroxyproline. In the presence of the sodium dodecyl sulfate (SDS) micellar phase, the EMOswere reversed when both the bidentate and tridentate ligands of the proline family were used. The resolution (Rs) ofenantiomers decreases when the cis-hydroxy substituent exists in D- or L-hydroxyproline. SDS micellar phase improvesthe resolution of amino acid enantiomers. The relationships among the EMO, ligand chirality, complex stability andstereo-selectivity are discussed.