Syntheses, crystal structures and properties of metal–organic rotaxane frameworks with cucurbit[6]uril†
Abstract
Five new metal–organic rotaxane frameworks (MORFs) have been hydrothermally synthesized by systematically combining cucurbit[6]uril-based pseudorotaxanes, rigid carboxylate ligands and d10 metal ions. Compound 1 presents a three-periodic pillared structure; 2 and 3 are two-periodic layers with hcb topologies; 4 presents a 3D structure with snw topology and 5 is a three-periodic network, featuring from interpenetrating to non-interpenetrating 3D MORFs. The cucurbit [6]uril-based MORFs obtained in this work illustrate the importance of non-covalent interactions around CB[6]s in the assembly of resultant super architectures. Furthermore, their TGA analysis, solid photoluminescence properties and sensitization to lanthanide ions are investigated.