PREASSOCIATING ALPHA-NUCLEOPHILES BASED ON BETA-CYCLODEXTRIN - THEIR SYNTHESIS AND REACTIVITY

Methods are reported for the attachment of alpha-nucleophiles to the p rimary and secondary sides of the cyclodextrin cavity. Six new materia ls have been prepared in which beta CD has been modified by hydrazine, hydroxylamine, oxime, and hydroperoxide functionalities. Transacylati ng studies with p-NPA have demonstrated that the primary-side hydroxyl amine shows the highest reactivity with a 1900-fold increase in rate o ver beta CD at pH 6.5. Other alpha-nucleophiles show less remarkable r ate increases in this system but, in some cases, demonstrate hydrogen- bonding to the cyclodextrin rim and inhibition kinetics.