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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]

Two new 3D coordination polymers, [Zn 3 (L) 2 (H 2 O) 4 ]·H 2 O ( 1 ) and [Zn 5 ( μ 3 -OH) 4 (L) 2 (H 2 O) 2 ] ( 2 ) (H 3 L = 3-(2′,5′-dicarboxylphenyl)benzoic acid), have been synthesized under hydrothermal conditions by adding different amounts of NaOH. Structural analyses show that both of them contain 1D inorganic Zn(II)-chains as rod-shaped secondary building units (SBUs) but they are in different forms. The rod-shaped Zn(II)-chain of 1 is only Zn-carboxylate chain, while the one in 2 is formed by the independent Zn 5 (COO) 6 clusters connected by hydroxyl oxygen. Furthermore, the thermal and luminescent properties of both compounds have been studied. [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: Four Ag(I)/Co(II) complexes based on a flexible V-shaped ligand 3,3′, 4,4′-diphenylsulfone tetracarboxylic acid (H4dstc), namely [Ag(bpe)2]·H3dstc (1), {[Ag2(H2dstc)(bpp)(H2O)]·H2O} n (2), {[Co2(dstc)(bpe)2(H2O)2]·2H2O} n (3) and {[Co4(dstc)2(bpa)3(H2O)6]·7H2O} n (4) have been synthesized in the presence of different rod-like N-donor ligands 1,2-di(4-pyridyl)ethylene (bpe), 1,3-bis(4-pyridyl)propane (bpp), and 1,2-bis(4-pyridyl)ethane (bpa). In complex 1, the H3dstc– ligand does not take part in coordination but balances the charge by its one deprotonated carboxylate group. Complex 2 contains two different motifs: a cationic 1D chain [Ag(bpp)]+ and an anionic 1D meso-helix [Ag(H2dstc)(H2O)]–. Interestingly, the non-covalent hydrogen bonding interactions extend such simple discrete units or 1D chains into 3D supramolecular architectures. Complex 3 represents a 3D binodal 4-connected (64·82) network, while complex 4 can be simplified as a primitive cubic (pcu) network. In addition, the photoluminescence of 1 and 2 and the magnetism of 3 and 4 are investigated, respectively. [Copyright &y& Elsevier]

Abstract: Three ZnII/CdII-coordination polymers based on 2-propyl-4,5-imidazoledicarboxylate (H3pimdc), namely, [Zn(Hpimdc)H2O] n (1), [Cd(H2pimdc)2] n (2) and [Cd2(Hpimdc)2(bbi)0.5(H2O)2] n [bbi=1,10-(1,4-butanediyl)bis(imidazole)] (3), have hydrothermally been synthesized, which exhibit a systematic dimensional variation by changing the metal ions or introducing the auxiliary ligand. Complex 1 is a 1D zig-zag polymeric chain, which is finally extended into a 3D supramolecular network through (12) O–H⋯O H-bonding rings. Complex 2 shows a 2D layer comprised alternately arranged left- and right-handed helical chains. Complex 3 features a rare (3,3)-connected 83 network with opposite chiral layers in a slipped ABAB fashion. The photoluminescent properties and thermal stabilities of three complexes are also discussed. [Copyright &y& Elsevier]

Abstract: Based on 1H-imidazo[4,5-f][1,10]-phenanthroline (IP), 4,4′-oxybis(benzoic acid) (H2oba), and two different metal salts, two novel complexes were hydrothermally constructed, {[Cd2(oba)2(IP)2(H2O)]·H2O} n (1) and {[Mn2(IP)4(oba)2]·(oba)(H2O)2} n (2). Complex 1 exhibits a rare 2D→2D parallel interpenetration layer , which contains two same-hand chiral sheets with the space group. Complex 2 contains 1D left-hand helical chain with the C2 space group. Meanwhile, the dissociate oba and water molecules are connected to be a right-hand helical chain via hydrogen bonds, and form a twofold-interpenetrating structure. In addition, the two compounds also exhibit good thermal stability. [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]