Construction And Performance Of The Light-Operated Supramolecular Assemblies Based On Crown Ethers And Cucurbiturils

As an important and intriguing area in supramolecular chemistry, the construction of photoresponsive supramolecular assemblies based on the macrocyclic hosts and the relative guests has attracted more and more attention. The investigations on their structures and functions not only help us understand the non-covalent bonds, but also promote the development of smart materials and nanoscience. Herein, we have designed and constructed some novel photoresponsive supramolecular assemblies, based on the unique complexation behaviors of macrocyclic hosts including crown ethers and cucurbiturils and the relative guests. Furthermore, their switchable self-assembly behaviors under external stimuli have also been investigated. The details are as follows:1. The general aspect of supramolecular chemistry was discussed briefly. Some representative results on photochromic materials and host macrocyclic such as compounds crown ethers and cucurbiturils were reviewed.2. A dual-stimulus luminescent lanthanide molecular device based on an unsymmetrical diarylperfluorocyclopentene was constructed.[2]Pseudorotaxane formed from an unsymmetrical diarylperfluorocyclopentene and a Eu3+complex of terpyridinyldibenzo-24-crown-8revealed excellent reversible lanthanide luminescence switching behavior dual-modulated by host-guest and optical stimuli.3. Two supramolecular complexes were successfully achieved by the controlled selective complexation process of cucurbit[8]uril (CB[8]) with hetero-guest pair containing azobenzene and bispyridinium moieties in aqueous solution, exhibiting the reversibly light-driven movements of CB[8] upon the photocontrollable isomerization of azophenyl axle components. Significantly, the obtained bistable supramolecular complexes and their corresponding [2]pseudorotaxanes could act as a promising concentrator and cleavage agent to regulate the binding behaviors with DNA molecules.4. Novel linear ruthenium(II) supramolecular assemblies was successfully constructed by the orthogonal self-assembly of bis(terpyridine) ruthenium(II) metal-ligand and benzo-24-crown-8based on host-guest complexation. Photoelectric properties of one-dimensional linear assemblies have been researched in detail.