A rotaxane having a ring molecule composed of a metaphenylene unit which swings as a pendulum and a dianthrylethane unit which undergoes isomerization in response to external stimuli was synthesize...
synthesized rotaxanes whose rates of rocking motion (pendular motion) were switched reversibly through changes to the size of the ringcomponent in response to external stimuli. The ring molecules of the rotaxanes incorporate a metaphenylene unit, which swings like a pendulum, and a dianthrylethane unit, which undergoes reversible isomerization in response to photo- and thermal stimuli and changes the size
system. The setup consists of dibenzylammonium hexafluorophosphate and a photochromic dianthrylethane-based [24]crown-8-type macrocycle, which we designed as a key ring component for the pseudorotaxane system having photocontrollable threading functionality by changing the size of ring component due to the action of light.