Nanohoop Rotaxanes via Active Template Syntheses and Their Potential in Sensing Applications

The synthesis of nanohoop rotaxanes via two different active template strategies is reported. By preparing triazole-embedded rotaxanes, the observation of metal binding events in both organic and aqueous conditions are readily observed via dramatic changes in nanohoop emission. Inspired by this result, we then describe the design and synthesis of a new type of "self-destructing" nanohoop rotaxane that, in the presence of an analyte, releases a quenched nanohoop macrocycle resulting in a bright fluorescence response. More broadly, this work highlights the conceptual advantages of combining compact π-rich macrocyclic frameworks with mechanical bonds formed via active-template syntheses.