Controlling phase in low-nuclearity calixarene-capped porous coordination cages with ligand functionalization†
Abstract
Porosity in low-nuclearity coordination cages is relatively rare as cages with larger pore sizes are usually targeted as a way to increase gas adsorption capabilities in this promising class of molecular adsorbents. This work presents the design, synthesis, and characterization of a series of carbazole dicarboxylic acid bridged calixarene capped cages that exhibit significant porosity to N2 and CO2 given their limited size, presenting with Braun–Emmett–Teller (BET) surface areas in excess of 450 m2 g−1 and 350 m2 g−1, respectively. Furthermore, we report, to the best of our knowledge, the first class of calixarene capped cages bridged by a ligand with a 90° bridging angle in addition to the first permanently porous calixarene cage to utilize Mn2+ cations.