Selective Host–Guest Binding of Anions without Auxiliary Hydrogen Bonds: Entropy as an Aid to Design

Abstract

Entropy matters! In contrast to classic host–guest design, which employs dedicated enthalpic interactions of the binding partners, the novel electroneutral host 1 binds its anionic guests by virtue of an overwhelmingly positive entropy of association. The prime driving force is guest desolvation. Despite the total omission of hydrogen bonding, host 1 is one of the best electroneutral receptors known for binding anions in polar solution.