Directional Transportation of a Helic[6]arene along a Nonsymmetric Molecular Axle.

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.