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Updated: Jul 14, 2026

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of Chalcogenidoplumbates(II or IV)
Published on: December 29, 2016
Reversible solid-state reaction between 18-Crown[6] and M[H2PO4](M = K, Rb, Cs) and an investigation of the
Dario Braga1, Marco Polito, Elena Dichiarante
1Department of Chemistry G. Ciamician, Via F. Selmi 2, 40126 Bologna, Italy. dario.braga@unibo.it
Abstract:
On heating the hydrated complexes 18-Crown[6].M[H(2)PO(4)].xH(2)O (x= 2 for M = K, Rb; x= 1.5 for M = Cs), quantitatively prepared by mechanical mixing of crystalline 18-Crown[6] and M[H(2)PO(4)], to ca. 60 degrees C, water loss takes place, accompanied by the extrusion of the crown ether from the crystalline complex and followed by reconstruction of the inorganic phase M[H(2)PO(4)](M = K, Rb, Cs); the resulting solid mixture reverts to 18-Crown[6].M[H(2)PO(4)].xH(2)O (x= 2 for M = K, Rb; x= 1.5 for M = Cs) upon grinding in air.
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