Application of a New Type of 3-Chloro-5-methylphenylcarbamate-β-cyclodextrin-bonded Silica Particles as Chiral Stationary Phase for Multi-mode HPLC

A new type of beta-cyclodextrin-bonded chiral stationary phase (CSP), partially substituted 3-chloro-5-methylphenylcarbamate-(3-(2-O-beta-cyclodextrin)-2-hydroxypropoxy)-propylsilyl-appended silica particles (35CMP-CD-HPS), has been successfully synthesized and applied as CSP in HPLC under normal-phase, reversed-phase and polar organic mobile phase conditions. The new stationary phase 35CMP-CD-HPS was characterized by means of elementary analysis and Fourier transformation infrared spectroscopy. The chromatographic performance of 35CMP-CD-HPS-packed column was evaluated by separating positional isomers of disubstituted nitrophenol and nitroaniline and enantiomers of some chiral drug compounds. The results showed that 35CMP-CD-HPS exhibited excellent separation selectivity for the aromatic positional isomers and the enantiomers of a wide range of chiral drug compounds. Besides the concurrently existed electron-withdrawing chlorine and electron-donating methyl groups at symmetry-equivalent meta-positions of the phenylcarbamate-substituted moieties, both the hydroxyl residues of the partially substituted beta-cyclodextrin and the stable ether spacer linking to the wider torus rim of beta-cyclodextrin in the new 35CMP-CD-HPS phase play important roles in chromatographic separations under multi-mode mobile phase conditions.