Working Supramolecular Machines Trapped in Glass and Mounted on a Film Surface.

Two surface-tethered nanomachines have been constructed at a supramolecular level by employing cylinders of the π-electron deficient tetracationic cyclophane, cyclobis(paraquat-p-phenylene) (blue), inside which polyether pistons incorporating π-electron rich dioxynaphthalene units (red and pink) can be induced to move when reductants are supplied either by chemicals or from a light source with 9-anthracenecarboxylic acid (yellow) as the photosensitizer and ethylenediaminetetraacetate (green) as a sacrificial reagent.