Nanosponges based on self-assembled starfish-shaped cucurbit[6]urils functionalized with imidazolium arms

A new porous material based on the first supramolecular cucurbituril-based nanosponge was synthesized by the functionalization of cucurbit[6]uril with twelve 1-(2-bromoethyl)-3-methyl-1H-imidazol-3-ium arms. The porous structure and the high adsorption capacity were demonstrated through surface area measurements and carbon dioxide adsorption. The new supramolecular sponge showed attractive properties such as (i) a highly porous structure that allowed CO2 capture, (ii) the possibility to reuse the adsorbed CO2 for organic synthesis, and (iii) an exciting thermal stability up to around 800 degrees C, with the potential use of this material in high temperature reactions. Finally, the reuse of CO2 was successfully investigated in the carboxylation reaction of phenylacetylene.