Redox‐Driven Intramolecular Anion Translocation between a Metal Centre and a Hydrogen‐Bond‐Donating Compartment

Dicationic ligands incorporating two 2,2′‐bipyridine units and two imidazolium moieties, [ 1 ] 2+ and [ 2 ] 2+ , form stable chelate complexes with Cu II and Cu I in acetonitrile solution. Each Cu II complex binds two X − ions according to two stepwise equilibria, the first involving the Cu II centre and the second involving the bis‐imidazolium compartment. Cu I complexes are able to host only one NO 3 − ion in the bis‐imidazolium cavity, while other anions induce demetallation. Thus, in the presence of one equivalent of NO 3 − , the Cu II /Cu I redox change makes the anion translocate quickly and reversibly from one binding site to the other within the [Cu II,I ( 1 )] 4+/3+ system, as demonstrated by cyclic voltammetry and controlled‐potential electrolysis experiments.