Stimuli-responsive supramolecular gel constructed by pillar[5]arene-based pseudo[2]rotaxanes via orthogonal metal–ligand coordination and hydrogen bonding interaction

Abstract

A pseudo[2]rotaxane formed from a dimethoxypillar[5]arene host and an amide-functionalized pyridine derivative guest was constructed in CHCl₃, which could further assemble into a linear supramolecular polyrotaxane upon adding Pd(OAc)₂via the incorporation of metal–ligand coordination. Furthermore, the obtained polyrotaxane could self-assemble to form a supramolecular gel at high concentration, which showed external stimuli-responsiveness.