Journal
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
Volume 139, Issue 36, Pages 12793-12803Publisher
AMER CHEMICAL SOC
DOI: 10.1021/jacs.7b07317
Keywords
-
Categories
Funding
- LIA-CNRS CLUSPOM
- LABEX CHARMMMAT
- University of Versailles Saint Quentin
- RFBR [17-53-16006]
- CNRS, region Ile de France through DIM Nano K
Ask authors/readers for more resources
Herein, we report on a three-component supra molecular hybrid system built from specific recognition processes involving a Dawson-type polyoxometalate (POM) ,P2W18O62](6-), a cationic electron-rich cluster [Ta6Br12(H2O)(6)](2+), and gamma-cyclodextrin (gamma-CD). Such materials have been investigated using a bottom-up approach by studying the specific interactions between gamma-CD and both types of inorganic units. Their ability to interact has been investigated in the solid state by single-crystal X-ray diffraction (XRD) and in solution using multinuclear NMR methods (including DOSY, EXSY, and COSY), electrospray ionization mass and UV-vis spectroscopies, electrochemistry, and isothermal titration calorimetry experiments. Single-crystal XRD analysis reveals that POM:gamma-CD constitutes a highly versatile system which gives aggregates with 1:1, 1:2, and 1:3 stoichiometry. Surprisingly, these arrangements exhibit a common feature wherein the gamma-CD moiety interacts with the Dawson-type POMs through its primary face. We present also the first structural model involving an octahedral-type metallic cluster with gamma-CD. XRD study reveals that the cationic [Ta6Br12(H2O)(6)](2+) ion is closely embedded within two gamma-CD units to give a supramolecular ditopic cation, suitable to be used as a linker within extended structure. Solution study demonstrates clearly that pre-associations exist in solution, for which binding constants and thermodynamic parameters have been determined, giving preliminary arguments about the chaotropic nature of the inorganic ions. Finally, both building blocks, i.e., the ditopic supramolecular cation {[Ta6Br12(H2O)(6)]@2CD}(2+) and the Dawson-type anion, react together to give a three-component, well-ordered hybrid material derived either as a supramolecular hydrogel or single crystals. The solid-state structure shows an unprecedented helicoidal tubular chain resulting from the periodic alternation of POM and supramolecular cation, featuring short hydrogen-bonding contacts between the electron-poor POM and electron-rich cluster. The 1D tubular ionic polymer observed in the single crystals should make it possible to understand the long-range ordering observed within the hydrogel hybrid material. The supramolecular chemical complementarities between the gamma-CD-based ditopic cation and POM open a wide scope for the design of hybrid materials that accumulate synergistic functionalities.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available