Amphiphilic Organic Cages: Self‐Assembly into Nanotubes and Enhanced Anion‐π Interactions

Abstract An amphiphilic organic cage was synthesized and used as self‐assembly synthon for the fabrication of novel functional supramolecular structures in solution. The transmission electron microscopy (TEM) results showed that this amphiphilic cage self‐assembled in aqueous solution into unilamellar nanotubes with a diameter of 29±4 nm at a concentration of 0.05 mg mL−1. Interestingly, the self‐assembly of this cage significantly enhanced the anion‐π interactions as indicated by a remarkable increasement of association constant (Ka) between Cl− and this amphiphilic cage after self‐assembly. In specific, Ka was increased from 223 M−1 for discrete cages in methanol to 6800 M−1 for aggregated cages after self‐assembly in water at the same concentration of 2.26×10−5 M. A mechanism based on a synergistic effect was proposed in order to explain this self‐assembly process through enhanced anion‐π interactions.