Noncovalent Assembly of [2]Rotaxane Architectures

Abstract

Reversible zinc–pyridine coordination and hydrogen-bonding interactions have been used to assemble a [2]rotaxane from three components. Cooperativity in the macrocyclization process that results in the porphyrin dimer (see picture) makes the system exceptionally stable. However, the kinetic lability of the zinc–porphyrin interaction means the dimer is in dynamic equilibrium with its monomer, and this has been exploited in the construction of a [2]rotaxane.