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A new macrocyclic arene, helic[1]triptycene[3]arene H, was conveniently synthesized in 37% yield by a one-pot reaction starting from 2,6-dimethoxyl-3,7-dihydroxymethyltriptycene. Macrocycle Hshowed fixed conformation in solution and could form 1:1 complexes with a series of neutral guests, secondary ammonium salts, and tertiary ammonium salts in both solution and solid states. The association constants between Hand the neutral guests were between (1.23 ± 0.10) × 102and (4.70 ± 0.47) × 103M–1, while the association constants between Hand the ammonium guests were between (1.35 ± 0.12) × 103and (1.59 ± 0.14) × 105M–1. Moreover, Hshowed bigger association constants with secondary ammonium salts than those with tertiary ammonium salts possibly because of the steric hindrance effect and multiple intermolecular interactions. The stimuli-responsive complexation between Hand the ammonium salts could be controlled by the addition and removal of acids and bases as well. Based on the host–guest complexation between Hand the secondary ammonium salt, [2]rotaxane was further synthesized, and its shuttling motion could be efficiently controlled by an acid and base.

Directional transportation of a helic[6]arene along a nonsymmetric molecular axle was achieved, which was easily performed in dichloromethane by a stopper reaction and subsequent addition of fluoride ions. In this system, the fluoride ions could act as a versatile stimulus to unidirectionally release the macrocycle that not only destroyed the host–guest interaction but also removed the silyl stopper.