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A lead carboxylate–azolate framework, [Pb3(μ4‐O)(L)2(H2O)] ⋅ 2H2O (1), has been constructed from the reaction of 2‐methyl‐4‐(1H‐tetrazol‐5‐yl) benzoic acid (H2L) and Pb(NO3)2 under solvothermal conditions. Compound 1 contains an unprecedented hexanuclear cluster [Pb6(μ4‐O)2(COO)4(CN4)2], which as an 8‐connected node is connected by 3‐connected L linkers to give rise to a three‐dimensional framework with an uncommon (3,8)‐connected tfz‐d; UO3 topology. Framework 1 possesses strong solid‐state yellow luminescence (563 nm), which stems from ligand‐to‐metal charge transfer (LMCT), however, the removal of water molecules in 1 lead to the significant luminescent decrease of the sample. Importantly, in the presence of 1, the thermal decomposition of ammonium perchlorate is significantly accelerated. MOFs make things faster: A metal‐organic framework (MOF) based on hexanuclear [Pb6(μ4‐O)2(COO)4(CN4)2] clusters was prepared by using a 2‐methyl‐4‐(1H‐tetrazol‐5‐yl) benzoic acid ligand. The MOF has a (3,8)‐connected tfz‐d; UO3 topology, and undergoes luminescence changes caused by the removal of water. It also accelerates the thermal decomposition of ammonium perchlorate. [ABSTRACT FROM AUTHOR]

From the same starting materials, two novel metal–organic frameworks, namely {(cation)[Cu 4 (bptca) 2 (OH)(H 2 O) 2 ]· x (solvent)} n ( 1 ) and {(cation)[Cu 3 (bptca) 2 (H 2 O) 3 ]· y (solvent)} n ( 2 ) (H 4 bptca = biphenyl-2,3,3′,5′-tetracarboxylic acid), have been synthesized through the linkage of Cu 2 (COO) 4 paddle-wheel clusters. The complex 1 possesses both dinuclear [Cu 2 O 2 ] subunits encapsulated into cage-like units and tetranuclear [Cu 4 ( μ 3 -OH) 2 ] clusters, which exhibits an unusual 3D 4-nodal (4,4,4,8)-connected network with {4 12 .8 12 .10 4 }{4 3 .8 3 } 4 {4 6 }{8 6 } topology. Reducing the metal-to-ligand ratio, the other 3D (4,4)-connected framework 2 with {4 2 .8 4 } PtS-type topology was constructed under the intervention of mononuclear Cu(bptca) 2 and single Cu 2 (COO) 4 paddle-wheel supporting layers. Notably, both of the frameworks 1 and 2 accommodate infinite open 1D nanosized quadrate channels. [ABSTRACT FROM AUTHOR]

Abstract: Five novel transition metal (Zn, Cd, Mn and Co)-based coordination polymers 1–5 with a flexible rodlike N,N′-donor ligand (bbi=1,1′-(1,4-butanediyl)bis(imidazole))and four O-donor polycarboxylate anions (H2oxa=oxalic acid; H2fma=fumaric acid; H2bpdc=2,2′-biphenyldicarboxylic acid; H4cit=citric acid) have been successfully synthesized and characterized by elemental analysis, IR spectra, and X-ray diffraction, namely {[Zn(bbi)3(NO3)]Br·2H2O} n (1), [Zn(oxa)(bbi)] n (2), [Mn(fma)2(bbi)2(H2O)2] n (3), [Cd2(bpdc)2(bbi)2] n (4) and {[Co8(cit)4(bbi)6(H2O)10]·7H2O} n (5). Compounds 1–5 display various coordination motifs due to different conformations of the bbi ligand, at the same time, owing to diverse coordination modes of the polycarboxylate ligands. And the effect of the polycarboxylate ligands plays important roles in the construction of extended networks. Compounds 1, 2 and 5 all exhibit 2D layer structures, in which 1 displays a 3-fold interpenetration framework containing 2D networks with (6,3) topology and 2 is a 2D structure with (4,4) topology. Compound 5 contains a 2D 44 grid-like layer with (44·62) topology composed of octanuclear cobalt clusters. Two high-dimensional compounds (3D) with a microporous network, containing 1D flower-like metal–organic motifs interlinked by bbi ligands for 4 and a 3-fold interpenetrating network with 66-dia topology by considering the manganese ion as a four-connected node for 3, are observed. The biological activities of the title compounds have been studied. The results indicate that 1–5 exhibit certain selective antimicrobial activities against Escherichia coli, Staphylococcus aureus and Enterobacter aerogenes, besides, 5 exhibits more obvious radical-scavenging activities than that of bbi ligand. Furthermore, Solid-state properties of thermal stability and the photoluminescence properties at room temperature for these crystalline materials have also been investigated. [Copyright &y& Elsevier]

Abstract: Three new fluorous coordination polymers with a fluorinated carboxylate tecton and N-donor co-ligands, {[Zn2(hfipbb)2(phen)2]·2H2O} n (1), [Zn2(hfipbb)2(bipy)(H2O)] n (2), and [Zn5(hfipbb)4 (Hhfipbb)2 (bpp)] n (3), [H2hfipbb=4,4′-(hexafluoroisopropylidene)bis(benzoic acid), phen=1,10-phenthroline, bipy=4,4′-bipyridine, and bpp=1,3-bi(4-pyridyl)propane], have been prepared and characterized by elemental analysis, IR spectra, and X-ray diffraction. Compound 1 exhibits a 3D supramolecular network assembled from two independent 1D chain motifs [Zn(hfipbb)(phen)] through π⋯π stacking, and C–H⋯F and O–H⋯O interactions. Compound 2 features 2D undulating layer structure with 44-sql network. Whereas, in compound 3, pentanuclear [Zn5(η 2-O)2(μ 2-η 1:η 1-CO2)]2− cores are bridged by hfipbb2− and bpp ligands into a 3D 6-connected sxd framework with a point symbol of (33·46·55·6). The diverse arrangements of the compounds show the modulation of the heterocyclic N-donor co-ligands can suitably mediate the coordination requirement of metal centers as well as the binding modes of fluorinated carboxylate tecton, which consequently generate diverse crystalline architectures. In addition, the properties of thermogravimetric analysis, X-ray powder diffraction, and photoluminescent behaviors of the compounds have also been discussed. [Copyright &y& Elsevier]