Stationary Phase for Gas Chromatography on the Basis of a Precursor of Macroheterocycles and a Nematic Liquid Crystal

• Published in: Russian journal of general chemistry Vol. 89; no. 3; pp. 574 - 579
• Main Authors: Kuvshinova, S. A., Novikov, I. V., Kuvshinov, G. V., Litov, K. M., Burmistrov, V. A., Islyaikin, M. K., Koifman, O. I.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.03.2019; Springer; Springer Nature B.V
• Subjects: Activity coefficients; Camphor; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chromatography; Enthalpy; Gas chromatography; Liquid crystals; Nematic crystals; Organic compounds; Phase transitions; Selectivity; Sorbents; Substitutes; Temperature; selectivity; stationary phase; nematic liquid crystal; gas chromatography; sorption; precursor of macroheterocycles
• ISSN: 1070-3632; 1608-3350
• DOI: 10.1134/S1070363219030381

The stationary phase for gas chromatography on the basis of the chiral R (+)-1′,7′,7′-trimethylbicyclo-[2.2.1]heptano[2′,3′- b ]-2,3-dicyanopyrazine (10.4 wt %) and a liquid crystalline 4,4′-dihexyloxyazoxybenzene was studied. The phase transition temperatures of the binary mixture were measured by polarizing microscopy. It was shown that the chiral camphor-substituted 2,3-dicyanopyrazine induces formation of an enantiotropic chiral helically coiled nematic phase in the achiral liquid crystal over a wide temperature range. The gas chromatographic retention times of organic compounds on this sorbents were measured. The structural and chiral selectivity of the stationary phase on the basis of a liquid crystal and camphor-substituted 2,3-dicyanopyrazine was determined. The retention volumes, activity coefficients, and sorption enthalpies and entropies were calculated and analyzed.