Assemblies of cucurbit[6]uril-based coordination complexes with disulfonate ligands: From discrete complexes to one: From two-dimensional polymers

Chen, Kai; Hua, Zi Yi; Li, Ran; Peng, Yu Ying; Zhu, Qiang Zhao; Zhao, Jiang Lin; Redshaw, Carl

Abstract

In this work, the combination of cucurbit[6]uril (Q[6]) with various naphthalene disulfonates and alkaline-earth metal ions allows for successful isolation of 9 novel Q[6]-based coordination complexes with the formulas [Ca(H2O)4(Q[6])0.5(1,5-NDA)0.5]·(1,5-NDA)0.5·3H2O (1), [Sr(H2O)4(Q[6])0.5(1,5-NDA)0.5]·(1,5-NDA)0.5·4H2O (2), [Ba(H2O)4(Q[6])0.5(1,5-NDA)0.5]·(1,5-NDA)0.5·4H2O (3), [Ca(H2O)5(Q[6])0.5](2,6-NDA)·9H2O (4), [Sr(H2O)5(Q[6])0.5]·(2,6-NDA)·6H2O (5), [Ba2(H2O)7(Q[6])(2,6-NDA)2]·11H2O (6), [Sr(H2O)4(Q[6])0.5(2,6-NDA)0.5]·(2,6-NDA)0.5·5H2O (7), [Ca2(H2O)10(Q[6])](2,7-NDA)·14H2O (8) and [Sr(H2O)5(Q[6])(2,7-NDA)]·4H2O (9) (H2NDA = naphthalenedisulfonic acid). Structural analysis revealed that the carbonyl groups of Q[6] bind directly to the alkaline-earth metal ions to form 1D coordination chains. Moreover, the metal ions are also linked to the disulfonate substituents of the naphthalenes, which, in the case of 9, resulted in a simple coordination complex, for 6, a 1D Q[6]-NDA-M2+ chain, and in the case of 1-3 and 7, 2D networks. By contrast, for 4, 5 and 8, the disulfonate ligands do not bind to the metals, and instead, act as supramolecular linkers. The resultant 3D supramolecular architecture of these compounds was constructed through various noncovalent interactions, particularly involving outer-surface interactions of the Q[6]s. Furthermore, the fluorescence properties of species 2 and 7 were investigated, and sensing experiments indicated that both were capable of functioning as fluorescent sensors for Fe3+ with high sensitivity and selectivity.

Citation

Chen, K., Hua, Z. Y., Li, R., Peng, Y. Y., Zhu, Q. Z., Zhao, J. L., & Redshaw, C. (2021). Assemblies of cucurbit[6]uril-based coordination complexes with disulfonate ligands: From discrete complexes to one: From two-dimensional polymers. CrystEngComm, 23(2), 465-481. https://doi.org/10.1039/d0ce01456g

• Journal Article Type: Article
• Acceptance Date: Nov 10, 2020
• Online Publication Date: Nov 13, 2020
• Publication Date: Jan 14, 2021
• Deposit Date: Nov 16, 2020
• Publicly Available Date: Nov 14, 2021
• Journal: CrystEngComm
• Electronic ISSN: 1466-8033
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 23
• Issue: 2
• Pages: 465-481
• DOI: https://doi.org/10.1039/d0ce01456g
• Keywords: General Materials Science; General Chemistry; Condensed Matter Physics
• Public URL: https://hull-repository.worktribe.com/output/3663353
• Publisher URL: https://pubs.rsc.org/en/Content/ArticleLanding/2020/CE/D0CE01456G#!divAbstract