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A novel and efficient copper-catalyzed homocoupling of ketoxime carboxylates has been developed for the synthesis of symmetrical pyrroles. This reaction tolerates a wide range of functional groups and provides a synthetically useful process to synthesize valuable symmetrical pyrroles under mild conditions. [ABSTRACT FROM AUTHOR]

Self-assembly of manganese acetate with 1,3-bis(4-carboxy-phenoxy)propane (H2bcp) and 1,2-bis(4-pyridyl)ethene (bpe) under solvothermal conditions yielded a polymer {[Mn2(bcp)2(bpe)(DMF)]} n (1), which shows 2-D → 3-D inclined interpenetration with polyrotaxane character. The magnetic behavior of 1 shows antiferromagnetic exchange between Mn magnetic centers. [ABSTRACT FROM AUTHOR]

Two unprecedented three-dimensional (3D) true coordination polymorphs, namely, [Pb2(phda)2(H2O)]n·2nH2O (1a, and 1b) (H2phda = 1,4-phenylenediacetate acid), which show distinct novel topological networks, have been successfully prepared by utilizing a kinked flexible H2phda. This work shows the first example of two different isomers reported for a flexible ligand acting as a bridge. Two unprecedented three-dimensional (3D) PbII coordination polymorphs, namely, [Pb2(phda)2(H2O)]n·2nH2O (1a, and 1b) (H2phda = 1,4-phenylenediacetate acid), which show distinct novel topological networks, have been successfully prepared by utilizing a kinked flexible H2phda. This work shows the first example of two different isomers reported for a flexible ligand acting as a bridge. [ABSTRACT FROM AUTHOR]

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]

By reacting an asymmetry semi-rigid Y-shaped/L-shaped linker H3cpta (H3cpta = 3-(4'-carboxyphenoxy)- phthalic acid) and Co(CH3COO)3'6H2O under different N-donor ligands in different solvents, three new Co-based coordination polymers, [Co3(cpta)2(bpe)3(H2O)4] (1) [Co(μ2-H2O)(μ3-OH)(Hcpta)(bpe)(H2O)' 3(DMF)3(H2O)] (2) and [Co3(cpta)2(bpa)4] (3) have been obtained. They exhibit trinodal topological nets/ layer, based on Co2+ ions and Y-shaped/L-shaped carboxylate linkers. 1 and 3 present 3D frameworks with the point symbol {4·102}2{105·12}{4·85}2 for 1 and {4·82}3{85·9}{4·67·92}3 for 3. While, 2 exhibits a 2D layer with the point symbol {4·6·8}{4·62·83}{62·8}. The magnetic studies indicate that all of the three complexes show antiferromagnetic exchanges transmitted through μ3-carboxylate/μ4-carboxylate bridges, μ2- H2O molecules and μ3-OH ions between Co2+ ions, respectively. And the result of this research shows that the solvent and the secondary ligands could co-regulate coordination polymer with interesting properties, providing a constructive guidance when synthesizing versatile topologies with the same organic spacer but a different architecture. [ABSTRACT FROM AUTHOR]

Twoisomeric metal–organic frameworks, consisting of Co-triazolatelayers and positional isomeric dicarboxylate pillars, both show distincttemperature-dependent CO2sorption behaviors. Because ofthe pores functionalized by amino groups, both materials have highCO2uptake and highly selective sorption of CO2over CH4and N2. [ABSTRACT FROM AUTHOR]

Three new 3D Mn(ii)-MOFs have been synthesized via solvothermal reaction with MnCl2·4H2O and [1,1′:4′,1′′-terphenyl]-2′,4,4′′,5′-tetracarboxylic acid (H4tptc) in three different solvents [N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMA) and N,N-dimethylformamide (DMF)], namely, [Mn2(tptc)(H2O)(NMP)]·NMP (1), [Mn2(tptc)(H2O)(DMA)]·DMA (2) and Mn2(tptc)(DMF)2 (3), all of which were fully characterized. In 1 and 2, the 1D uniform Mn–carboxylate chains with the (μ-EO-H2O/NMP/DMA)(μ-COO)2 triple bridges (EO = end-on) are extended by the tptc linkers to form a 3D (3,4)-connected fry net with 1D irregular quadrangular channels. Interestingly, 3 possess two kinds of Mn–carboxylate chains and can also be simplified as a fry net. The self-assembly synthesis system responds to small carbonyl solvents (NMP, DMA and DMF) with very high sensitivity and selectivity, but products using hydroxy solvents (methanol, alcohol and isopropanol) were not identified. The various pore frameworks of 1–3 are filled by different coordinated and latticed solvent molecules in their channels. The sizes of the channels [3 (33.11 Å2) ＜ 2 (35.17 Å2) ＜ 1 (35.37 Å2)] are induced by the sizes of the solvent molecules (DMF ＜ DMA ＜ NMP). The good chemical stabilities of 1–3 were observed. Magnetic studies demonstrate that the magnetic coupling through the mixed carboxylate bridges in all compounds is antiferromagnetic. [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]

In contrast to monoalkylmonoarylketoxime carboxylates, dialkylketoxime carboxylates do not react under the employed conditions. [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]

By reacting a tritopic ligand 5-(4-carboxyphenyl)nicotinicacid(H2cpna) with Co(NO3)2under differentconditions, two new three-dimensional (3D) frameworks, [Co2(cpna)2(H2O)3]·DMF·9(H2O) (1) and [Co4(cpna)4(H2O)8] (2), have been obtained. Theyexhibit (3,6)-connected topological nets based on Co2clustersand Y-shaped trinodal cpna2–linkers. 1presents a chiral anhnet with the right-handed helicalchannels, while 2shows an achiral framework with a rtltopology. The whole structures of 1and 2are constructed from 2D achiral layers interconnected bytriangular cpna2–nodes. Notably, these layers containtwo heterochiral vertical and parallel 21helical chainsfor 1and 2, respectively, and those chainsare constructed with 4-connected tetrahedral or square planar centersin their respective layers. The magnetic studies indicate that 1and 2show antiferromagnetic and weak ferromagneticexchanges transmitted through μ2-Owater/μ1,3-carboxylate bridges and carboxylate singleμ2-O bridges between Co2+ions in theCo2dimers, respectively. In addition, 1displaysmicroporous sorption for N2and CO2. [ABSTRACT FROM AUTHOR]

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]

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]