Halogen‐Bonding Strapped Porphyrin BODIPY Rotaxanes for Dual Optical and Electrochemical Anion Sensing

Anion receptors employing two distinct sensory mechanisms are rare. Herein, we report the first examples of halogen‐bonding porphyrin BODIPY [2]rotaxanes capable of both fluorescent and redox electrochemical sensing of anions. (1)H NMR, UV/visible and electrochemical studies revealed rotaxane axle triazole group coordination to the zinc(II) metalloporphyrin‐containing macrocycle component, serves to preorganise the rotaxane binding cavity and dramatically enhances anion binding affinities. Mechanically bonded, integrated‐axle BODIPY and macrocycle strapped metalloporphyrin motifs enable the anion recognition event to be sensed by the significant quenching of the BODIPY fluorophore and cathodic perturbations of the metalloporphyrin P/P(+.) redox couple.