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By employing the ligand 2-(isonicotinamido)terephthalic acid (H 2 L) containing the amide functional groups, a Cd-MOF, {[Cd 2 L 2 (H 2 O) 2 ]·4H 2 O} n (1) has been constructed by solvothermal synthesis. The dinuclear clusters [Cd 2 (COO) 2 ] in 1 are linked by the pyridinyl and carboxylate groups of ligands to form a three-dimensional (3D) skeleton, containing 1D channels with the free amide groups. The activated framework shows good stability in water and high selectivity for CO 2 over CH 4. The open Cd2+ site as Lewis acidic center makes the MOF achieve efficiently catalytic conversion for CO 2 cycloaddition with epoxides. Furthermore, 1 also exhibits good chemical stability in water, allowing the detection for ronidazole (RDZ) and dimetridazole (DTZ) with the low detection limit and rapid response. A Cd-MOF with excellent stability in water and strong fluorescence has been constructed by a pyridyl-carboxyl ligand with amide groups, which reveals high adsorption selectivity for CO 2 over CH 4 , efficiently catalytic conversion of CO 2 and epoxides, and selective fluorescence sensing for ronidazole (RDZ) and dimetridazole (DTZ) in water. Image 1 • A stable-water porous Cd(II)-MOF containing open metal ion sites was synthesized. • MOF shows efficiently catalytic conversion for the CO 2 cycloaddition with epoxides. • MOF shows sensitive fluorescent sensing for ronidazole and dimetridazole in water. [ABSTRACT FROM AUTHOR]

To develop efficient adsorbent materials for storage and separation of C2H2, an unprecedented supercage MOF, [Me2NH2]⋅[Zn3(ALP)(TDC)2.5]⋅3.5DMF⋅2 H2O (1) was constructed through medicinal molecule allopurinol (ALP) and S‐containing 2,5‐thiophenedicarboxylic acid (H2TDC). 1 contains a novel linear trinuclear cluster that is composed by ALP and carboxylates and forms a final uncommon 5‐connected yfy topological framework. The framework possesses three types of interlinked cages decorated by rich functional sites, and reveals not only high adsorption capacity for C2H2 but also excellent selective separation for C2H2/CO2 and C2H2/CH4 at 298 K. Dynamic breakthrough experiments on C2H2/CO2 (1:1) mixture and C2H2/CH4 (1:1) mixture also demonstrated the potential of the material to separate C2H2 from CO2 or CH4 mixtures. Molecular simulations were also studied to identify the different CO2‐ and C2H2‐ binding sites in 1, such as carboxylate groups, S atoms and carbonyl groups. [ABSTRACT FROM AUTHOR]

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]

By systematic change of the solvothermal synthesis, three new coordination polymers, [Cd(L)∙(H2O)]∙2H2O (1), [Cd(L)∙(H2O)]∙H2O (2), and [Cd(L)] (3), have been synthesized based on a tritopic ligand 4-(pyridin-3-yl)isophthalic acid (H2L). Compounds 1 and 2 show very similar two-dimensional (2D) bilayers further linked by interlayer hydrogen bonds into three-dimensional (3D) supramolecular structures, while 3 displays a 3D structure constructed form one-dimensional (1D) Cd-carboxyl chains. Notably, 1 and 2 have a pair of unusual isomers with the opposite orientation of coordinated H2O on the metal centers, leading to different hydrogen bonding interactions. Thermal stabilities and solid-state photoluminescences for 1-3 were also investigated. [ABSTRACT FROM AUTHOR]

Using a triazole carboxylic ligand (H2L = 4-(1H-1,2,4-triazol-1-yl) isophthalic acid), four water-stable lanthanide metal-organic frameworks (Ln(III)-MOFs) (1-Ln, Ln(III) = Tb, Eu, Dy, and Sm), [Ln(L)(HL)(H2O)2], where the deprotonated H2L ligands have two different coordination modes: L2− and HL− [(a): η2μ2χ2, η2μ1χ2; (b): η2μ1χ2], have been synthesized by solvothermal reaction and characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analyses show that Ln(III)-MOFs are isostructural with 2D-layered structures with uncoordinated carboxylic and triazole groups. The luminescent properties of 1-Tb in aqueous solution containing different cationic solutions and small organic solvents have been explored under ultraviolet irradiation at room temperature. The high quenching constant KSV values and low detection limits indicate that 1-Tb exhibits extremely high detection sensitivity and selectivity toward Fe3+ ions and nitrobenzene; 1-Tb can keep its original network and be reused after the sensing experiments, which provide us with an optical material for detecting Fe3+ ions and nitrobenzene. Magnetic studies show that antiferromagnetic exchange interactions exist between Dy(III) ions in 1-Dy. [ABSTRACT FROM AUTHOR]

By employing a carboxylate ligand derived from benzene-1,4-dicarboxylate, a chemically stable Zn4O-based self-penetrating metal–organic framework has been rationally synthesized, which exhibits high CO2 adsorption and efficient catalytic conversion for CO2 cycloaddition. [ABSTRACT FROM AUTHOR]

Four new isostructural lanthanide–organic frameworks, [Ln(L)(H2O)2]·H2O·CH3CN (1-Ln) (Ln = Eu, Tb, Dy, and Gd), have been successfully synthesized via solvothermal reactions with a semi-rigid V-shaped multicarboxylate ligand 2-(2′,4′-dicarboxylphenoxy) benzoic acid (H3L) and Ln(NO3)3·6H2O. 1-Ln shows 2D layer-by-layer frameworks with interlayer channels decorated by carboxylate groups. 1-Eu exhibits excellent luminescence properties, and therefore, is chosen as a probe for sensing different metal ions and anions. Consequently, 1-Eu displays high selectivity and sensitivity for Fe3+ and Cr6+ ions, simultaneously, through the luminescence quenching effect, and thus, should be an excellent candidate for probing these pollutant metal ions. In addition, antiferromagnetic exchange interactions also exist between the Dy3+ ions in 1-Dy. [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]

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]

Three new Cd(ii)-MOFs, [Cd(L1)0.5(bpp)] (1), [Cd(L1)0.5(bipy)] (2), and [Cd(L2)0.5(bipy)] (3) [H4Ln = (1,1′:4′,1′′-terphenyl)-2′,x,x′′,5′-tetracarboxylic acid (n = 1, x = 3, and n = 2, x = 4), bpp = 1,3-di(4-pyridyl)propane, and bipy = 2,2′-bipyridine], have been synthesized using Cd(ii) ions and isomeric H4Ln ligands in the presence of auxiliary ligands via solvothermal reaction, and have been fully characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Complex 1 is a three-dimensional (3D) pillar-layered network built from L14− and bridging bpp co-ligands with a binodal (4,8)-connected gsp2 topology and a symbol of (44·62)(416·612). 2 was successfully synthesized using bipy instead of the bpp ligand used to assemble 1 giving a 2D 4-connected sql net. 3 is a 3D reticular framework with [Cd2(COO)4] SBUs based on L24− ligands, displaying a (4,4)-connected lvt (42·84) topology. X-ray diffraction analysis revealed that the structures of the MOFs can be mediated by the steric effect of the tetracarboxylate and secondary co-ligands. The solid-state luminescence properties of the MOFs were measured carefully by ultraviolet irradiation at room temperature. In particular, 3 exhibited a high sensitivity for Fe3+ in aqueous solutions of mixed metal ions, which makes it a promising crystalline material to be a luminescent probe for Fe3+. Importantly, 3 can keep its original framework and be reused in sensing experiments. The sensing mechanism has also been studied in detail. [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]

By a less-exploited strategy, a stable framework was constructed by using 4,4'-biphenyldicarboxylic acid (H2bpdc) and methyl-functionalized 3,3',5,5'-tetramethyl-4,4'-bipyrazole (H2bpz) coligands, revealing a new (6,8)-connected net based on two extremely rare trinuclear and tetranuclear metal-carboxylate-pyrazolate clusters. The framework is very porous and possesses not only high CO2 loadings but also very high CO2/N2 selectivities at 308 and 313 K because of the polar pore surface decorated by clusters, pyrazolyl units, and confined cages with methyl groups dangling. Importantly, GCMC simulation identified two favorable CO2 sorption sites located sequentially near Co3(pz)3 and Co3(CO2)2(pz) motifs of the tetranuclear cluster, and the multipoint framework-CO2 interactions were distinguished. The framework also displays remarkable stability toward water and organic solvents. [ABSTRACT FROM AUTHOR]

Sixnew metal-organic frameworks (MOFs) with structuresranging from a one-dimensional (1D) chain, two-dimensional (2D) layer, even 2D double layer to three-dimensional (3D) network based on 2,2'-bipyridine-3,3'-dicarboxylate-1,1'-dioxide(H2bpdado) and N-donor ligands (1,2-bis(4-pyridyl)ethane(bpa) or 1,2-trans-bis(4-pyridyl)ethene (bpe)),namely, [Cd(bpdado)(H2O)2]n(1), {[Cd2(bpdado)2(bpa)(H2O)2]·DMF·3H2O}n(2), {[Cd2(bpdado)2(bpe)(H2O)2]·8.5H2O}n(3), {[Pb2(bpdado)2(bpa)]·10H2O}n(4), {[Pb2(bpdado)2(bpe)]·10H2O}n(5), [Pb2(bpdado)Cl2(H2O)2]n(6), were synthesized by hydro(solvo)thermal and/or diffusionmethods. In these complexes, the bpdado ligand shows four types of coordination modes, three of which appeared for the first time. Polymers 1-6present diverse motifs with differentmetal ions and different conformations and/or coordination modes ofbpdado, which may show a natural synergy in structural diversity ofthe resultant MOFs. Under the similar synthetic conditions just withdifferent metals (Cd(II) and Pb(II)), 6exhibits a 2Dcovalent grid layer, whereas complex 1displays a 1Dchain. Meanwhile, Cd(II) atom in 1shows an unprecedentedtriangular prism coordination geometry. Although bpe/bpa ligands actas pillars between 2D [M(bpdado)]nlayersubunits in complexes 2-5, the Cd(II)-basedcomplexes 2and 3are extended into a 3Dlayered-pillared network, while the Pd(II)-based complexes 4and 5just exhibit the 2D double layers. Moreover, the 2D [Cd(bpdado)]nlayer subunits of 2and 3can be derived from replacing hydrogenbonds in 1D 1with coordination bonds dependent on differentcoordination modes of bpdado. In addition, the solid-state luminescence(for 1-6) and gas adsorption properties(for 2and 3) have been studied and discussedin detail. [ABSTRACT FROM AUTHOR]

Four new coordination polymers (CPs), [Co3(L)2(bib)3(EtOH)2]·2H2O (1), [Mn3(L)2(bib)2(H2O)4]·4H2O (2), [Ni(HL)(bib)(H2O)3] (3) and [Ni3(bib)4(H2O)10]·2(L)·12(H2O) (4), were synthesized under solvothermal conditions with an unsymmetrical tricarboxylic acid ligand [biphenyl-3,3',5-tricarboxylic acid (H3L)] in the presence of the 1,4-bis(1H-imidazol-4-yl)benzene (bib) ligand. In compound 1, tricarboxylate acid ligands (H3L) link Co centers to generate two-dimensional (2D) layers which are further connected by bib ligands to exhibit a three-dimensional (3D) framework with a (4,4,5)-connected (4²·6³·8)2(4²·67·8)2(64·8·10) topology. The three-dimensional (3D) framework of 2 is defined as a (3,3,4)-connected topology with the point symbol of (6·8²)2(6²·8)2(8·104·12). Compound 3 contains a one-dimensional (1D) left-hand helix chain along the a direction and further extends into a 2D supramolecular network and a 3D supramolecular framework via hydrogen bonds. Compound 4 displays a one-dimensional (1D) molecular ladder, which is further combined with each other through π...π stacking to extend into 2D supramolecular sheets. The supramolecular networks of 3 and 4 resulted from the different solvent ratios [V(H2O)-V(EtOH)] in the reaction. All the CPs are characterized by single-crystal X-ray diffraction analyses, powder X-ray diffraction (PXRD), elemental analyses, IR spectroscopy, and TGA analyses. Moreover, the weak ferromagnetic properties of 2 and 3 and antiferromagnetic properties of 1 and 4 have also been investigated. [ABSTRACT FROM AUTHOR]

A novel and facile copper-catalyzed 5-endo-trig cyclization of ketoxime carboxylates for the synthesis of 2-arylpyrroles has been developed. The reaction tolerates a range of functional groups and is a practical procedure for rapid synthesis of 2-arylpyrroles in high yields under mild conditions. [ABSTRACT FROM AUTHOR]

A novel and efficient Cu-catalyzed intermolecular 5-endo-trig cyclization of ketoxime carboxylates for the synthesis of 2-arylpyrroles is developed. [ABSTRACT FROM AUTHOR]