First the cation, then the anion. This describes the complexation of alkali metal halides with bifunctional receptors like that on the right (R = n‐octyl) based on calixarenes. The uncomplexed ligand has a strong intramolecular hydrogen bond between the urea moieties, which is disrupted by the conformational change induced by complexation of a Na+ ion. Only then is an anion like Cl− bound in the upper portion of the calixarene.
|Journal||Angewandte Chemie, International Edition in English|
|Publication status||Published - 1996|