A 1,2,3,4,5-pentaphenylferrocene-stoppered rotaxane capable of electrochemical anion recognition

The chloride anion templated synthesis of an electrochemical anion sensory interlocked host system, prepared by the integration of redox-active 1,2,3,4,5-pentaphenylferrocene stopper groups into the structure of a rotaxane capable of binding anionic guests is described. Extensive ¹H NMR and electrochemical titration investigations were used to probe the anion recognition and sensing properties of the rotaxane, compared to the axle and model system components. A characteristic electrochemical response was observed for chloride binding by the rotaxane, which was attributed to the topologically constrained cavity of the interlocked host molecule. Topologically constrained host cavity for sensing chloride ions: Chloride anion templated synthesis of an electrochemical, anion sensory, interlocked host system, prepared by the integration of redox-active 1,2,3,4,5-pentaphenylferrocene stopper groups into the structure of a rotaxane (see picture), is described. A characteristic electrochemical response for chloride binding by the rotaxane is observed, attributed to the topologically constrained cavity of the interlocked molecule.