Expanding the enantioselectivity of the gas-chromatographic chiral stationary phase chirasil-val-C11 by doping it with octakis(3-O-butanoyl-2,6-di-O-n-pentyl)-gamma-cyclodextrin

Pavel A Levkin; Anna Levkina; Harri Czesla; Samuele Nazzi; Volker Schurig

doi:10.1002/jssc.200600279

Expanding the enantioselectivity of the gas-chromatographic chiral stationary phase chirasil-val-C11 by doping it with octakis(3-O-butanoyl-2,6-di-O-n-pentyl)-gamma-cyclodextrin

J Sep Sci. 2007 Jan;30(1):98-103. doi: 10.1002/jssc.200600279.

Authors

Pavel A Levkin¹, Anna Levkina, Harri Czesla, Samuele Nazzi, Volker Schurig

Affiliation

¹ Institute of Organic Chemistry, University of Tübingen, Tübingen, Germany.

PMID: 17313147
DOI: 10.1002/jssc.200600279

Abstract

Combination of the enantioselective properties of the two versatile gas-chromatographic chiral stationary phases (CSPs) octakis(3-O-butanoyl-2,6-di-O-n-pentyl)-gamma-CD (Lipodex E) 1 and L-valine-diamide-based CSP Chirasil-Val-C11 2 has been realized by doping the chiral polymer 2 with the nonpolymeric selector 1. The resulting mixed-mode CSP Chirasil-Val(gamma-Dex) 3 was found to have a greatly improved enantioselectivity toward proline and aspartic acid (as N-trifluoroacetyl ethyl or methyl esters) in comparison to the single-mode CSP 2. The presence of the CD selector in 3 extended the scope of gas-chromatographic enantioseparations achievable on 2 to underivatized alcohols, terpenes, and other chiral compounds that are exclusively enantioseparated on 1.