Cyclofructans and preferentially their derivatives can serve as chiral selectors for the separation of different enantiomers/atropisomers. Moreover, the strong ionophoric nature of the 18-crown-6 ether core of cyclofructan 6 for barium cations may be exploited to enhance or modify enantioselectivity. In this work isopropyl-cyclofructan-6 was used as a chiral selector for the separation of binaphthyl atropisomers in HPLC and CE. The data from both separation systems were compared with each other. While in HPLC the chiral selector was bonded to silica gel to afford a chiral stationary phase, in capillary electrophoresis it was freely mobile in the background electrolytes (BGE). This significant difference is reflected in the separation potential of the two separation systems. All five analytes could be baseline separated in HPLC (reversed phase mode) while only one derivative was baseline resolved in CE. This result was attributed to the more rigid nature of the immobilized chiral selector. Addition of Ba(2+) to the mobile phase or BGE improved chiral separations in both systems. The results may help to elucidate the interaction mechanism in these systems with cyclofructan derivatives and to gain some general knowledge of their separation potential.

Department of Analytical Chemistry Faculty of Science Palacký University in Olomouc 17 listopadu 12 Olomouc CZ 771 46 Czech Republic

Department of Chemistry and Biochemistry University of Texas at Arlington Arlington TX 76019 USA

Department of Physical and Macromolecular Chemistry Faculty of Science Charles University Prague Albertov 2030 Prague 2 CZ 128 43 Czech Republic

Regional Centre of Advanced Materials and Technologies Department of Analytical Chemistry Faculty of Science Palacký University in Olomouc 17 listopadu 12 Olomouc CZ 771 46 Czech Republic

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