HPLC on Calixarene Bonded Silica Gels. I. Characterization and Applications of the p-tert-Butyl-Calix[4]arene Bonded Material

摘要

Molecules containing cavities of well-defined dimensions are able to include guest molecules stereoselectively. This work is concerned with the introduction and evaluation of a newly developed high-performance liquid chrornatographic packing materialbased on caiix(4]arene chemically bonded to silica gel. It is well documented that calixarenes representing cyclic condensates of para substituted phenols and formaldehyde have the ability to form intracavity inclusion complexes with ions and organic molecules in aqueous solutions. The silica bonded macrocyclic ligands form truncated cones similar to cyclodextrins. Data are presented illustrating the resolution characteristics for disubstituted aromatics, peptides, nucleosides, and nucleobases. The results indicate that the calix[4]arene silica gel behaves predominantly as a reversed-phase material. Some effects support the assumption that the cavity acting as an electron donator can influence the elution order.