A switchable ferrocene-based [1]rotaxane with an electrochemical signal output.

A [1]rotaxane, in which a linear rod is attached to one cyclopentadienyl (Cp) ring of a ferrocene unit and threaded into a dibenzo-24-crown-8 connected to the other Cp ring, was prepared. The mechanical motion of the rod-like part relative to the macrocycle has been demonstrated using (1)H NMR spectroscopy. Cyclic voltammetry (CV) showed that the system can be chemically switched between electrochemically reversible and irreversible states, depending on the inclusion and exclusion of the ammonium/amine group from the macrocycle.