A hydrogen-bonded cluster with ‘onion-type’ structure, encapsulated and induced by a spherical cluster shell: [(H2O)n⊂ MoVI72MoV60O372(HCO2)30(H2O)72]42−

Abstract

By reacting an aqueous solution of ammonium heptamolybdate with formic acid in the presence of hydrazinium sulfate at pH ≈ 4.2 the compound (NH4)42[MoVI72MoV60-O372(HCO2)30(H2O)72]·xHCO2Na·yH2O 1 (x ≈ 30, y ≈ 250) with spherically shaped stable cluster anions is obtained; owing to the spherical shape of the cluster–shell template, the anion 1a (with the small ‘nondisturbing’ bidentate HCO2– ligand) exhibits a remarkable overall ‘onion-type’ structure, thereby revealing also a novel type of inclusion: a hydrogen-bonded cluster with ‘onion-type’ structure, which suggests interesting aspects for a new type of supramolecular chemistry.