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The combination of polyoxoniobates (PONbs) with 3d metal ions, azoles, and organoamines is a general synthetic procedure for making unprecedented PONb metal complex cage materials, including discrete molecular cages and extended cage frameworks. By this method, the first two PONb metal complex cages K4@{[Cu29(OH)7(H2O)2(en)8(trz)21][Nb24O67(OH)2(H2O)3]4} and [Cu(en)2]@{[Cu2(en)2(trz)2]6(Nb68O188)} have been made. The former exhibits a huge tetrahedral cage with more than 120 metal centers, which is the largest inorganic–organic hybrid PONb known to date. The later shows a large cubic cage, which can act as building blocks for cage‐based extended assembly to form a 3D cage framework {[Cu(en)2]@{[Cu2(trz)2(en)2]6[H10Nb68O188]}}. These materials exhibit visible‐light‐driven photocatalytic H2 evolution activity and high vapor adsorption capacity. The results hold promise for developing both novel cage materials and largely unexplored inorganic–organic hybrid PONb chemistry. [ABSTRACT FROM AUTHOR]

Abstract: A protein‐sized (ca. 4.2×4.2×3.6 nm3) non‐biologically derived molecule {Nb288O768(OH)48(CO3)12} (Nb288) containing up to 288 niobium atoms has been obtained, which is by far the largest and the highest nuclearity polyoxoniobate (PONb). Particularly, in terms of metal nuclearity number, Nb288 is the second largest cluster so far reported in classic polyoxometalate chemistry (V, Mo, W, Nb, and Ta). Nb288 can be described as a giant windmill‐like cluster aggregate of six nanoscale high‐nuclearity PONb units {Nb47O128(OH)6(CO3)2} (Nb47) joined together by six additional Nb ions. Interestingly, the 47‐nuclearity Nb47 units generated in situ can be isolated and bridged by copper complexes to form an inorganic–organic hybrid three‐dimensional PONb framework, which exhibits effective catalytic activity for hydrolyzing nerve agent simulant of dimethyl methylphosphonate. The unique Nb47 cluster also provides a new type of topology to very limited family of Nb‐O clusters. [ABSTRACT FROM AUTHOR]

Two zeolite-like cluster organic frameworks based on Cd-Cu/Mn-Cu heterometallic supertetrahedral secondary building units have been successfully constructed under solvothermal conditions, namely, Cu[Cd4Cu6(L)4(H2O)18](Ac)9 ⋅DMA ⋅3 H2O ( 1), and Cu[Mn4Cu6(L)4(Ac)3(H2O)12](Ac)6 ⋅CH3CN ⋅13 H2O ( 2), where H3L=2-(hydroxymethyl)-2-(pyridin-4-yl)-1,3-propanediol, Ac=CH3COO−, DMA= N, N′-dimethylacetamide. Single-crystal X-ray structural analysis reveals that both 1 and 2 exhibit 3-dimensional zeolite-like architectures with similar 4-connected components, but possess definitely different topologies of diamondoid (dia) and uncommon lonsdaleite (lon), respectively. 1 and 2 represent the first cases of zeolite-like cluster organic frameworks containing Cd-Cu/Mn-Cu heterometallic supertetrahedral secondary building units. Furthermore, the magnetic properties and porous nature of 1 and 2 were also studied. [ABSTRACT FROM AUTHOR]