MIV molecular oxo-clusters (M=Zr, Hf, Ce, Th, U, Np, Pu) are prolific in bottoms-up material design, catalysis, and elucidating reaction pathways in nature and in synthesis. Here we introduce Ce70 , a wheel-shaped oxo-cluster, [CeIV 70 (OH)36 (O)64 (SO4 )60 (H2 O)10 ]4- . Ce70 crystallizes into intricate high pore volume frameworks with divalent transition metals and Ce-monomer linkers. Eight crystal-structures feature four framework types in which the Ce70 -rings are linked as propellers, in offset-stacks, in a tartan pattern, and as isolated rings. Small-angle X-ray scattering of Ce70 dissolved in butylamine, with and without added cations (CeIV , alkaline earths, MnII ), shows the metals' differentiating roles in ring linking, leading to supramolecular assemblies. The large acidic pores and abundant terminal sulfates provide ion-exchange behavior, demonstrated with UIV and NdIII . Frameworks featuring CeIII/IV -monomer linkers demonstrate both oxidation and reduction. This study opens the door to mixed-metal, highly porous framework catalysts, and new clusters for metal-organic framework design.
Keywords: SAXS; cerium; polyanions; supramolecular chemistry; transition metals.
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