Anion Recognition of 2,3-Disubstituted Cyclodextrin Derivatives in a Mixed Solvent of Acetnitrile and Water

Abstract

In this study, we investigated the use of cyclodextrins (CDs) as scaffolds for constructing anion receptors. 1-3 ), in which the hydroxyls on C-2 and C-3 are protected by benzyl, acetyl, or propionyl groups; moreover, we investigated their anion binding properties in CD 3 CN or CD 3 CN/D 2 O (99/1, v/v) using 1 H-NMR titration experiments. The results demonstrate that CD-based receptors ( 1-3 ) effectively bind with AcO (cid:237) and H 2 PO 4 (cid:237) by cooperative intermolecular hydrogen bondings with alcoholic hydroxyl groups on C-6. The selectivity trends thought to be a function of the basicity of the anions and the size of the binding pocket in the receptors.