Spatially Directional Resorcin[4]arene Cavitand Glycoconjugates for Organic Catalysis.

The synthesis of novel spatially directional multivalent resorcin[4]arene cavitand glycoconjugates (RCGs) and their ability to catalyze organic reactions is reported. The β-d-glucopyranoside moieties on the upper rim of the "bowl"-shaped resorcin[4]arene cavitand core are capable of multiple hydrogen-bond interactions resulting in a pseudo-cavity, which has been investigated for organic transformations in aqueous media. The RCGs have been demonstrated to catalyze thiazole formation, thiocyanation, copper(I)-catalyzed azide alkyne cycloaddition (CuAAC), and Mannich reactions; they impart stereoselectivity in the three-component Mannich reaction. Thermodynamic values obtained from (1) H diffusion-ordered spectroscopy (DOSY) experiments suggest that the upper saccharide cavity of the RCG and not the resorcin[4]arene cavity is the site of the complexation event.