Iptycenes in supramolecular and materials chemistry

Iptycenes, including triptycene as the smallest member, are rigid molecules with shapes that lead them to form open structures with substantial "free volume". There is a great deal of excitement in the application of these molecules to supramolecular chemistry, where researchers have taken advantage of their unique properties to construct new molecules and materials, including molecular machines, novel liquid crystals, and porous polymers for chemical sensing. This tutorial review highlights the application of iptycenes to the supramolecular chemistry of crystal engineering, host-guest complexes, molecular machines, polymers, and liquid crystals.