The empirical comparison of cyclofructans and cyclodextrins as chiral selectors in capillary electrophoretic separation of atropisomers of R,S-1,1'-binaphthalene-2,2'-diyl hydrogen phosphate

Abstract

Native cyclofructans and their isopropyl derivatives were studied as chiral selectors in capillary electrophoresis and compared with α- and β-cyclodextrin. R,S-1,1'-Binaphthalene-2,2'-diyl hydrogen phosphate was used as a model chiral compound. The empirical observation of the enantioselectivity of native cyclofructans and isopropyl derivatives of cyclofructans was described and compared with the cyclodextrins. The influence of methanol and acetonitrile, as the most commonly used organic solvents, and sodium dodecyl sulfate as a micelle forming additive on the separation of R,S-1,1'-binaphthalene-2,2'-diyl hydrogen phosphate atropisomers was achieved. The different enantiorecognition abilities resulting from unlike interaction mechanism with R,S-1,1'-binaphthalene-2,2'-diyl hydrogen phosphate were observed for the studied cyclodextrins and cyclofructans, especially when methanol or sodium dodecyl sulfate were used as modifiers of the separation conditions.

Keywords: Atropisomers; Capillary electrophoresis; Cyclodextrin; Cyclofructan; Enantioseparation.