Efficient control of movement in non-photoresponsive molecular machines by a photo-induced proton-transfer strategy.

The movement of three pairs of different non-photoresponsive rotaxanes can be efficiently controlled by visible light through a photo-induced proton-transfer (PIPT) strategy in the presence of the photoacid 1-MEH. Moreover, the PIPT strategy also provides systems with a good fatigue resistance after more than 50 cycles.