A cyclodextrin-based molecular shuttle containing energetically favored and disfavored portions in its dumbbell component

A molecular shuttle containing dodecamethylene units, 4,4'-bipyridinium units, and alpha-cyclodextrin (alpha-CD) has been prepared. Shuttling behavior is solvent and temperature-sensitive and could be controlled by double interactions: hydrophobic interaction between a CD ring and a station and a repulsive interaction between a CD ring and a linker. This is a novel method to control the mobility of a bead in a molecular shuttle.