Construction of a Molecular Switch and Selector under Electrochemical Control.

In this work, we designed and synthesized a special axle guest hexyldimethyl(ferrocenylmethyl)ammonium ( ) bromide. The binding interactions of and its oxidized form with cucurbit[7]uril (Q[7]) and cyclohexanocucurbit[6]uril (Cy6Q[6]) were investigated by H NMR, cyclic voltammogram, and isothermal titration calorimetry techniques. Our data indicate that both hosts Cy6Q[6] and Q[7] can form stable [2]pseudorotaxanes with in their different redox states. Most importantly, the combination and dissociation of the hosts with the guest as well as the binding location can be controlled by electrochemical means, which develops a special molecular switch and selector.