Efficient synthesis of a labile copper(I)-rotaxane complex using click chemistry

Copper(I)-induced threading of 5,5′-diazidomethyl-2,2′-bipyridine through a coordinating ring followed by reaction of a propargyl ether attached to a stopper group leads to the desired rotaxane in 62% yield. The reaction is carried out under the ‘click chemistry’ conditions with 0.75 equiv of additional copper(I).