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Three new isostructural 3D lanthanide metal–organic frameworks (Ln‐MOFs), {H[LnL(H2O)]⋅2 H2O}n (1‐Ln) (Ln=Eu3+, Gd3+ and Tb3+), based on infinite lanthanide‐carboxylate chains were constructed by employing an ether‐separated 5,5′‐oxydiisophthalic acid (H4L) ligand under solvothermal reaction. 1‐Eu and 1‐Tb exhibit strong red and green emission, respectively, through the antenna effect, as demonstrated through a combination of calculation and experimental results. Moreover, a series of dichromatic doped 1‐EuxTby MOFs were fabricated by introducing different concentrations of Eu3+ and Tb3+ ions, and they display an unusual variation of luminescent colors from green, yellow, orange to red. 1‐Eu with channels decorated by ether O atoms and the open metal sites displays good performance for CO2 capture and conversion between CO2 and epoxides into cyclic carbonates. [ABSTRACT FROM AUTHOR]

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]

Twomicroporous metal–organic frameworks, [Zn2(HDDCBA)]·2DMF·2H2O (1) and [Cd2(DDCBA)·DMA·H2O]·H2N(Me)2(2) havebeen synthesized under solvothermalcondition by using a less-exploited symmetrical pentacarboxylate ligand,3,5-di(3′, 5′-dicarboxylphenyl)benozoic acid (H5L). Both compounds 1and 2revealthe (5,5)-connected nets based on the binuclear metal clusters andorganic linkers. The desolvated structure of 1(1a) contains two shapes of 1D channel with suitable pore sizeand polar system decorated by uncoordinated carboxylate groups. Asa result, 1apossesses not only high CO2loadingbut also excellent CO2/CH4selectivity at 273and 298 K. In addition, both compounds display solid-state luminescencestemming from the ligand-centered fluorescence of H5L. [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]

Three new solvent-directed three-dimensional (3D) lead(ii) coordination polymers, [Pb2(L)2]n (1), [Pb3(L)3]n (2) and [Pb(L)]·H2O (3) [H3L = 2-(pyridine-2-yl)-1H-imidazole-4,5-dicarboxylic acid], have been synthesized solvothermally. As influenced by different solvent systems, compounds 1 and 3 exhibit varying architectures from a multi-nodal 3,3,4,4-connected to a uninodal 3-connected net, while 2 with helices represents a binodal 3,4-connected topological net. Moreover, 3 possesses a micropore which is decorated with pyridyl systems and uncoordinated carboxylate oxygen atoms. In addition, the small-sized and highly polar pores enable 3 to attract CO2 strongly, leading to a high sorption heat for CO2 and significant selectivity for CO2 over H2 and N2 at 293 K. The luminescent behaviors and emissive lifetimes of 1–3 are also discussed. [ABSTRACT FROM AUTHOR]

Under solvothermalconditions, six new Zn(II) coordination polymers,[(CH3)2NH2]2[Zn(L)]·2H2O (1), [Zn2(L)(py)2] (2), [Zn2(L)(bpe)2]·bpe·6H2O (3), [Zn2(L)(bpe)(DMA)(H2O)]·5H2O (4), [Zn2(L)(bpy)0.5(H2O)2]·2.5H2O (5), and [Zn2(L)(bpe)(H2O)]·3H2O (6) [H4L = 5,5′-(p-xylylenediamino)-1,1′,3,3′-(benzenetetra-carboxylicacid), py = pyridine, bpy = 4,4′-dipyridine and bpe = 1,2-bis(4-pyridyl)ethane],have been synthesized by employing a flexible tetracarboxylic acidH4L and different auxiliary pyridine-based ligands. In 1–6, all L4–ligandsare 4-connected nodes; however, the diverse configurations of thetwo terminal isophthalate units of L4–around thecentral −NHCH2PhCH2NH– spacerlead to various topological nets. 1shows a three-dimensional(3D) 2-fold interpenetrated 4-connected dianetwork resultingfrom the vertical configuration of the two isophthalate units of L4–. 2displays a 3D (4,4)-connected ptsnet in which the two isophthalate units of L4–adopt a parallel configuration. The two isophthalate units of L4–in 3are also almost parallel, resultingin an intriguing 3D 2-fold interpenetrated network with the (4,4)-connected bbfnet. 4is a two-dimensional bilayer structure,extending into a 3D supramolecular framework through interlayer hydrogen-bondinginteractions. 5and 6disclose similar 3Dstructural architectures, in which the two isophthalate units of L4–are almost vertical and exhibit tetrahedral topologicalnodes, inducing a rare (4,5)-connected xwwnet and anunprecedented (4,6)-connected network, respectively. The thermal stabilitiesand luminescent properties of 1–6have also been studied in detail. The complexes exhibit intensesolid-state fluorescent emissions at room temperature. [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: 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]