Early Attempts and Current Status

Pioneering attempts at using cinchona alkaloids as a platform for chiral stationary phase preparation have been reported as early as in the mid-1950s by Grubhofer and Schleith [52]. The chiral anion exchange polymeric materials were prepared by immobilization of quinine (and other cinchona alkaloids) via the 9-hydroxyl group or quinuclidine nitrogen to a polymer support. However, this resulted in very low selectivities of these phases toward racemic mandelic acid as a test analyte. Results of the early studies have been reviewed in detail by Davankov [53]. 

The chiral discrimination process studied for quinine and binaphthol 29 (R = i-Pr) by using 1H NMR spectroscopy led to the conclusion that the primary forces responsible for the enantiodiscrimination are the hydrogen bonds and steric interactions [57, 58], Optimization studies on quinine for the enantioseparation of carbinol 28 (Ar = 9-anthryl, R = CF3) on quinine CSP 25 carried out by Nesterenko et al. showed that under normal conditions the best selectivity (a 1.53) could be 

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