Polyoxometalate condensation and transformation mediated by adaptive coordination-assembled molecular flasks
Journal
Chemical Science
Journal Volume
16
Journal Issue
18
Start Page
7956
End Page
7962
ISSN
2041-6520
2041-6539
Date Issued
2025
Author(s)
Abstract
Here we report polyoxometalate (POM) condensation or transformation reactions mediated by adaptive coordination-assembled molecular flasks. Addition of Na2SiO3 to the (Mo6O19)2⊂1·(NO3)8 complex containing Lindquist-type clusters as guests leads to the formation of a new (SiMo12O40)⊂2·(NO3)8 host-guest complex, where the in situ generated Keggin-type cluster served as a trigger for the host transformation from cage 1 to isomeric bowl 2. Conversion from 1 to 2 driven by the in situ condensation was found to be 27.5-fold faster than the direct templation with independently prepared SiMo12O404−. As a comparison, cage 1 was noticed to bind only one W6O192− cluster in its cavity, and the formation of (W10O32)⊂2·(NO3)8 as the main product and (SiW12O40)⊂2·(NO3)8 as the minor host-guest complex was observed when it was used for the above condensation reaction, highlighting the crucial role of encapsulation in cavity-confined POM transformations. The reaction processes and the final structure of all the new host-guest complexes have been investigated by NMR, ESI-TOF-MS and SCXRD. Our findings not only showcase a unique example of inorganic-reaction-driven responsive supramolecular system, but also provide a new approach for the preparation of functional POMs⊂cage composite materials.
Publisher
Royal Society of Chemistry (RSC)
Type
journal article