“<i>ortho</i>-Wurster's Crowns”: Synthesis and Properties of a Novel Phenylenediamine-Based Redox-Active Macrocyclic Ligand

A hybrid, macrocyclic structure based on o-phenylenediamine and a crown ether promotes an intimate mutual interaction with a bound potassium ion in the form of chelation by the redox-active moiety. A general synthetic method and properties are described for the first member of a new class of redox-active, lariat-type macrocycles called the “o-Wurster's crowns”.