US EPA

8523290 

Journal Article 

Resolution of enentiomeric amides on a pirklet-type chiral stationary phase. A comparison of subcritical fluid and liquid chromatographic approaches 

Macaudiere, P; Tambute, A; Caude, M; Rosset, R; Alembik, MA; Wainr, IW 

1986 

Yes 

Journal of Chromatography A
ISSN: 0021-9673
EISSN: 1873-3778 

371 

C 

177-193 

English 

10.1016/S0021-9673(01)94704-1 

Subcritical and supercritical fluid chromatography (SubFC and SFC) have been evaluated for the resolution of an homologous series enantiomeric amides. the solutes were the 2-naphthoyl amides of an homologous series of amines, ranging from 2-aminobutane to 2-aminooctane, and the p-methyl-, p-methoxy- and p-chlorophenylamide of 2-aminoheptane. The chiral stationary phase (CSP) used was the covalent form of (R)-N-(3,5-dinitrobenzoyl)phenylgylcine. In liquid chromatography (LC) the mobile phase comprised hexane-2-propanol-acetonitrile (97:3:0.5) at a flow-rate of 2ml/min and temperatures of 20-35°C. In SFC, the mobile phases were various mixtures of carbon dioxide and polar modifiers, such as alcohols, chloroform and water. For the best conditions in LC, the chiral resolution, α, increased through the homologuos series from α = 1.03 for the amide derived from 2-aminobutane to α = 1.11 for the 2-aminooctane amide. The values of α observed for the π-basic amids of 2-aminoheptane(p-methyl and p-methoxy) were greater than that observed for the π-acidic amide (p-chloro), i.e., α = 1.08 versus 1.04. The selectives, resolutions and efficiencies obtained by LC and SubFC were similar. These results indicate that the mechanism of chiral recognition is the same in LC and SubFC and that the methods should be inerchangeable. The actual analysis time for SubFC was significantly shorter than that required for LC: as short as 2 min for the 2-aminooctane amide, whereas LC takes over 10 min under the best conditions. © 1986.