New metal–organic frameworks from triptycene: structural diversity from bulky bridges

Abstract

Four distinct triptycene-containing metal–organic frameworks, including three that are structural isomers, were synthesized and characterized. Structural isomerism was observed in the secondary building units of TMOF-2 giving rise to no fewer than three distinct [Zn₄O]⁶⁺ clusters. Structural integrity upon guest solvent removal was confirmed using powder X-ray diffraction and thermogravimetric analysis, but gas adsorption experiments were conducted and revealed no appreciable surface area. Triptycenyl groups incorporated into MOFs appear to enhance structural diversity, but also crowd the pores of the MOF, reducing accessible surface area.