Enantioselective separations of chiral molecules by μ‐HPLC and SFC on microbore and packed microcapillary columns

Abstract

New results obtained with microbore or microcapillary columns packed with DACH-DNB CSP (spherical silica, 5 pm) using conventional LC eluents or supercritical fluids are reported. Examples of direct chromatographic separations of complex mixtures of stereoisomers on: a) long, packed microbore or microcapillary columns and b) several columns coupled in series are shown; in the latter case, a home-made calculation procedure (Simulation for Multi-Column Chromatography -SMCC) was used to quickly select the optimal conditions (kind of stationary phases and relative columns length).

Toward enantioselective nano ultrahigh‐performance liquid chromatography with Whelk‐O1 chiral stationary phase

“…Recently monolithic capillary chiral stationary phases have been developed to overcome the problems in the preparation of packed capillary/nanocolumns, but their development is still in cradle . In literature, the use of the packed version of chiral columns, with nano and capillary dimensions, is mainly reported . Beside the development of hardware miniaturization, in the last 10 years, there has been an impressive evolution in terms of particle design leading to ultrafast separations without loss of efficiency and resolution.…”

Supercritical Fluid Chromatography and Extraction

“…Garcia et al described a derivatized cellulose-based CSP packing designed for rapid separations using microbore SFC (219). High-resolution microbore or microcapillary SFC separations were also performed using a novel CSP by D'Acquarica et al (220). These authors also modeled the separation and used this model to guide their selection of chromatographic conditions.…”

Twenty years of research on silica‐based chiral stationary phases

“…Sub-and supercritical fluid chromatographic (sub-FC and SFC) applications of CSP_1 were also presented in the context of packed analytical, microbore, and microcapillary columns [27][28][29][30]; some examples of enantio- meric separations were shown by using several columns coupled in series [28,30], and the influence of mobile phase temperature and composition was examined [28]. Efficient separations of the buckminsterfullerene C 60 and the related higher fullerene C 70 were performed using eluents based on either n-hexane or carbon dioxide [29].…”

“…= 0) allowed the application of the tandem arrangement of chiral plus racemic columns coupled in series, where it was necessary to increase the chemo-and/or the diastereo-selectivity of a given chromatographic system [1, 15,30]. In this context, we described for the first time the application of the racemic, non-enantioselective version of a CSP to maintain diastereoselection and extract energy barriers from simplified chromatograms, obtained for the stereolabile isomers of o-dinaphthylphenyl derivatives [31].…”