Transition metal templated formation of (2)- and (3)-rotaxanes with porphyrins as stoppers

A general precursor to rotaxane-type structures results from the transition metal-directed threading of a molecular fragment having a central chelate and an end-attached gold(III) porphyrin into a presynthesized coordinating ring. A copper(I)-complexed (2)-rotaxane and a new compartmental (3)-rotaxane result from the design of the second porphyrin's functioning as a good stopper, following threading.