Synthesis of A Bis‐Macrotricyclic Host and Its Complexation with Secondary Ammonium Salts: An Acid–Base Switchable Molecular Handcuff

A novel triptycene‐derived bis‐macrotricyclic host was designed and synthesized. The host was shown to form a 1:4 stable complex with 4 equiv. of dibenzylammonium salt in solution and in the solid state. Moreover, it was found that the host with multicavities could also self‐assemble with 2 equiv. of bis‐secondary ammonium salt to form a handcuff‐like structure under the tested condition ([1]0 = 3.0 mM). The complexation and decomplexation of the assembly could be further chemically controlled by the stimuli of acid and base.