Characterization of new R-naphthylethyl cyclofructan 6 chiral stationary phase and its comparison with R-naphthylethyl beta-cyclodextrin-based column
Abstract
Derivatized cyclofructans have been recently introduced as a new class of chiral selectors with great application potential. In this study, a R-naphthylethyl-functionalized cyclofructan 6 based chiral stationary phase (RN CF6 CSP) was used for separation of substituted binaphthyl catalysts in the normal phase HPLC mode.
Dominant interaction types that play a role in the separation mechanism were revealed by a linear free energy relationship (LFER) method. In order to evaluate the contribution of the substituent on the cyclofructan structure to retention, the R-naphthylethyl-functionalized beta-cyclodextrin (RN CD) CSP was chosen for comparison.
Retention factors of 46 widely different solutes. with known solvation parameters, were determined on each of the columns under the same mobile phase compositions used for the enantiomeric separations. The LEER results showed that hydrogen bond acidity and polarity/polarizibility have the greatest impact on retention and enantioresolution on the RN CF6 CSP.