Metal Ion‐Responsive Dynamics in a Homo [2]Catenane: Circumrotation and Pirouetting

Abstract We describe a homo [2]catenane that is stable in two conformations and demonstrates a large‐amplitude co‐conformational change during the exchange between Cu(I) and Co(III) metal ions. Each ring comprises a bi‐dentate diphenyl‐phenanthroline and a tri‐dentate pyridine‐diamide metal templating center. The presence of multiple coordination centers results in orthogonal complexation behavior with suitable metal ions, leading to a relative motion between the interlocked rings via pirouetting and circumrotation. Interconvertible catenates via homo [2]catenane have been characterized by 1H‐NMR, 13C‐NMR, mass, UV–visible spectroscopy, and variable temperature NMR experiments.