Cinchona-Modified Chiral HPLC

Significance

Cinchona alkaloid units were efficiently immobilized to silica gel via a 1,2,3-triazole linkage by click reactions. Thus, the cinchona derivatives bearing terminal alkyne groups a-d reacted with azidopropyl- or azidoundecyl-modified silica gel beads in the presence of Cu catalyst under Sharpless or Meldal conditions, where the cinchona units were covalently anchored onto the silica surface, in high yield to provide a series of enantiomerically modified silica gel. The resulting silica beads were used as a chiral stationary phase of HPLC packing whose enantioseparation performance was examined for HPLC analysis of several amino acid derivatives.