Nonconventional Three-Component Hierarchical Host–Guest Assembly Based on Mo-Blue Ring-Shaped Giant Anion, γ‑Cyclodextrin, and Dawson-type Polyoxometalate

• Published in: Journal of the American Chemical Society 2017-10, Vol.139 (41), p.14376-14379
• Main Authors: Moussawi, Mhamad Aly, Haouas, Mohamed, Floquet, Sébastien, Shepard, William E, Abramov, Pavel A, Sokolov, Maxim N, Fedin, Vladimir P, Cordier, Stéphane, Ponchel, Anne, Monflier, Eric, Marrot, Jérôme, Cadot, Emmanuel
• Format: Article
• Language: English
• Subjects: Chemical Sciences
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.7b08058

In this communication, we report on a noteworthy hybrid supramolecular assembly built from three functional components hierarchically organized through noncovalent interactions. The one-pot synthesis procedure leads to the formation of large Mo-blue ring-shaped anion {Mo154}, which contains the supramolecular adduct based on the symmetric encapsulation of the Dawson-type [P2W18O62]6– anion by two γ-cyclodextrin units. Such a nanoscopic onion-like structure, noted [P2W18O62]@2γ-CD@{Mo154} has been characterized by single-crystal X-ray diffraction, thus demonstrating the capability of the giant inorganic torus to develop relevant supramolecular chemistry, probing the strong affinity of the inner and outer faces of the γ-CD for the polyoxometalate surfaces. Furthermore, interactions and behavior in solution have been studied by multinuclear NMR spectroscopy, which supports specific interactions between γ-CD and POM units. Finally, the formation of this three-component hybrid assembly from one-pot procedure, in water and using nearly stoichiometric conditions, is discussed in terms of the driving forces orchestrating this highly efficient multilevel recognition process.