Anion receptors based on ureidocalix[4]arenes immobilised in the partial cone conformation†
Abstract
A novel method enabling the synthesis of receptors based on the calix[4]arenes immobilized in the partial cone conformation is reported. The application of a protection/deprotection strategy using nosyl groups enables the regioselective introduction of functional groups (NO2 and NH2) into the upper rim of calix[4]arenes, leading finally to the substitution pattern so far inaccessible to