Supramolecular Association between γ-Cyclodextrin and Preyssler-Type Polyoxotungstate

Abstract

The development of hybrid materials based on polyoxometalates constitutes a strategy for the design of multifunctional materials. The slow evaporation of an aqueous solution of [NaP5W30O110]14− in the presence of γ-Cyclodextrin (γ-CD) led to the crystallization of a K6Na8{[NaP5W30O110]•(C48H80O40)}•23H2O (NaP5W30•1CD) supramolecular compound, which was characterized by single-crystal X-ray diffraction, IR-spectroscopy, thermogravimetric and elemental analyses. Structural analysis revealed the formation of 1:1 {[NaP5W30O110]•[γ-CD]}14− adduct in the solid state. Studies in solution by cyclic voltammetry, electrochemical impedance spectroscopy, 1H NMR spectroscopy, and 31P DOSY, have demonstrated weak interactions between the inorganic anion and the macrocyclic organic molecule.

Infinite building blocks for directed self-assembly of a supramolecular polyoxometalate–cyclodextrin framework for multifunctional oxidative catalysis

“…Compared with the previously reported porous POM-CD supramolecular frameworks using POMs as MBBs, 22–32 1 represents the first example featuring interconnected channels along two dimensions constructed from ({MnV 12 Ce 6 }{PW 10 V 2 } 2 ) ∞ IBBs. First, the infinite nature of such IBBs makes it hard for them to approach the primary/secondary faces of α-CD due to the size mismatch; secondly, the embedded {PW 10 V 2 } bears a negative charge of −5, which makes it to preferentially interact with the external surface of α-CD according to the reported Hofmeister series of Keggin-type POMs where [BW 12 ] 5− is located outside γ-CD due to the weak Hofmeister efffect.…”

“…[22][23][24][25] Since the pioneering work of developing archetypal Keggin and Dawson-CD assemblies, 26,27 the scope of POM clusters has evolved from smaller Strandberg, Lindqvist and Anderson to bigger Preyssler, and even to gigantic Mo blue. 25,[28][29][30][31] In spite of these prominent advancements, the deliberate fabrication of porous ordered POM-CD systems is still challenging because of the dominant interacting modes between the POM clusters and native CDs mainly involving host-guest inclusion occurring at the primary or secondary face of CDs, which leads to easy blocking of the cavity of CDs and thus resulting in the formation of non-porous networks.…”

Water‐soluble Self‐assembled {Pd84}Ac Polyoxopalladate Nano‐wheel as a Supramolecular Host

“…It is a well‐established method in host‐guest chemistry to highlight differences in diffusion rates when guest species are bound to a host molecule compared to that of when it is moving freely. [ 52 , 53 , 54 , 55 , 56 ] Figure 5 shows that BV 2+ guest and {Pd 84 } Ac host tumble at an average rate of 401 pm 2 s −1 and 207 pm 2 s −1 , respectively when they are alone in solution. In a 1 : 7 solution of the two components there is a significant decrease in the average diffusion coefficients for BV 2+ to 144 pm 2 s −1 and {Pd 84 } Ac to 113 pm 2 s −1 .…”

Large anion binding in water

“…91 Most recently, Leclerc et al reported the formation of a 1 : 1 exclusion complex between γ-CD and a Preyssler-type anion, [NaP 5 W 30 O 110 ] 14− . 92 The large and highly charged anion interacts with the primary face of the γ-CD as revealed by single-crystal X-ray diffraction and 1 H NMR experiments.…”