High-Yielding Rotaxane Synthesis with an Anion Template.

An electrophile caught like a mouse in a trap! An anionic stopper-wheel complex acts as a supramolecular nucleophile in an almost quantitative synthesis of a phenyl ether rotaxane. The electrophilic semiaxle has to thread through the macrocycle in order to contact the bulky phenolate group that is positioned on the other side, and probably tightly held in place by hydrogen bonds.