Cucurbit[n]uril/metal ion complex-based frameworks and their potential applications

Abstract

Cucurbit[n]urils (Q[n]s) have the structural characteristic of two open portals rimmed with carbonyl groups, which make them coordinate with metal to form Q[n]-based MOFs. According to the type of Q[n]/metal ion-based complexes formed, Q[n]-based MOFs can be classified as those constructed using i) simple Q[n]/metal complexes, ii) 1D coordination polymers, iii) 2D coordination polymers, and iv) 3D coordination polymers, respectively. • Cucurbit[ n ]urils coordinate with metal using carbonyl groups to form Q[ n ]-based MOFs. • The structures of Q[ n ]-based MOFs are summarized. • TThe relationship between the structure of the Q[ n ]-based frameworks and their functional features are overviewed. Since the concepts of metal organic frameworks and coordination networks were proposed, the preparation of new structures and investigations on their properties has lead to the remarkable development of reticular chemistry and its applications with the basic principle of connecting simple building units to generate periodic frameworks. A rigid cavity with two opening portals make cucurbit[ n ]urils (Q[ n ]s) suitable as the building units for frameworks related to Q[ n ]/metal ion(M n+ ) complexes. According to the type of Q[ n ]/M n+ complexes used, the frameworks related to Q[ n ]/M n+ complexes can be classified as those constructed using i) simple Q[ n ]/M n+ complexes, ii) 1D coordination polymers, iii) 2D coordination polymers, and iv) 3D coordination polymers. The construction of frameworks related to Q[ n ]/M n+ complexes not only obtains elegant framework structures, but more importantly, can be used to explore the their adsorption characteristics and applications in separation, detection, catalysis, etc., to clarify the relationship between the structure and functional features of the Q[ n ]/M n+ -based frameworks, and to establish new research branches for Q[ n ] chemistry.