The threading−dethreading of a photoinactive pH-switchable calixarene bipyridinium pseudorotaxane in solution has been controlled by visible light irradiation using a merocyanine compound as a photoacid. The coupling between the two molecular switches that communicate with one another by intermolecular proton transfer provides a general principle for the operation of acid−base controllable molecular machines with light.
A Simple Molecular Machine Operated by Photoinduced Proton Transfer / Silvi, S.; Arduini, Arturo; Pochini, Andrea; Secchi, Andrea; Tomasulo, M.; Raymo, F. M.; Baroncini, M.; Credi, A.. - In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY. - ISSN 0002-7863. - 129(2007), pp. 13378-13379. [10.1021/ja0753851]