Guest induced transformations of assembled pyridyl bis-urea macrocycles

Abstract

Pyridine macrocycles with no cavities assembled into close packed columns yet absorbed guests including hydrogen, carbon dioxide, and iodine.Many different approaches have been used to design materials with open channels that display permanent porosity.1 Recent examples indicate that a permanent pore or channel is not necessarily a requirement for the absorption of gases.2 Dynamic structural changes in coordination polymers induced new channels into which guest molecules were incorporated.3 Atwood et al. recently demonstrated that non-porous organic solids could expand by gas induced transformations.4 In this manuscript, we report a pyridyl bis-urea host (1, Fig. 1) that assembled into columns with high fidelity.