Bis(calix[4]diquinone) Receptors: Cesium- and Rubidium-Selective Redox-Active Ionophores

A new class of redox-active ionophore comprised of two calix[4]diquinone moieties connected
through either alkylene or pyridylene linkages has been developed. Spectroscopic and electrochemical
investigations, X-ray crystal structure analyses, and molecular modeling studies show butylene- and
propylene-linked members of this family of redox-active receptors exhibit remarkable selectivity preferences
and substantial electrochemical recognition effects toward cesium and rubidium cations.