Supramolecular glass formation by arene-perfluoroarene pairing of three-dimensional macrocycles.

We report supramolecular glass formation by mixing two crystalline pillar[6]arenes bearing benzyl and pentafluorobenzyl substituents, even though neither compound exhibited a melting point. The glass formation was attributed to arene-perfluoroarene interactions and the sterically bulky, three-dimensional pillar[6]arene framework that hinders efficient packing.