Structure Of Coordination Polymer Research Articles

Synthesis and the crystal structure of a new chiral metal-organic coordination polymer based on l-proline-substituted 2-aminobenzene-1,4-dicarboxylic acid derivative

Synthesis and the crystal structure of a new chiral metal-organic coordination polymer based on l-proline-substituted 2-aminobenzene-1,4-dicarboxylic acid derivative

Achieving Multifunctional Detection of Th4+ and UO22+ in the Post‐Synthetically Modified Metal–Organic Framework and Application of Functional MOF Membrane

AbstractThe field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH2‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th4+, UO22+, and Cr2O72−, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th4+, UO22+ and Cr2O72−) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors.

Metal(II) Ion Dependence of the Structures and Properties of Square-Grid Coordination Polymers of Tetrabromobenzenedicarboxylate and Pyrazine as Bridging Ligands

Abstract In this study, we report the synthesis and crystal structures of coordination polymers employing tetrabromobenzenedicarboxylate (Br4bdc2−) and pyrazine (pyz). Uncoordinated pyz molecules are stabilized between the layers by both hydrogen H-bonding and π–π stacking interactions in [M(Br4bdc)(pyz)(H2O)2](pyz), where M = Co(II) and Zn(II). In addition, water molecules are incorporated between the layers in [Cu(Br4bdc)(pyz)(H2O)2](H2O) owing to Jahn–Teller distortion of the Cu(II) ions, which prevents π–π stacking interactions between the pyz and Br4bdc2−. Depending on the metal(II) centers, structural changes that occur during the heating and hydration processes exhibit different behavior. Co(II) compound slowly changes structure by heating and rapidly recovers the crystalline state in air. Conversely, Zn(II) compound assumes the amorphous phase by heating and slowly yields the crystalline phase in ambient conditions. Although the Cu(II) compound also shows structural changes by heating, the dehydrated phase exhibits hydrophobic characteristics. Ion conductivity measurements of the as-synthesized forms show conductivities of 1.9 × 10−6 Scm−1, 4.6 × 10−7 Scm−1, and 1.3 × 10−6 Scm−1, for the Co(II), Zn(II), and Cu(II) complexes at 90 °C and 95% relative humidity (RH), respectively. The relatively low values of the as-synthesized Co(II) and Zn(II) compounds are attributed to the H-bonding interaction and π–π stacking of pyz molecules, which prevent the dynamics of the pyz molecules needed for proton conduction.

Synthesis, structure and magnetic properties of an oxamate-based 1D coordination polymer built on pentametallic links

The solvothermal reaction of the hexadentate 2-(oxamato)benzoic acid ligand (oaba) with copper(II) and cobalt(II) ions has yielded the [Cu4Co3(oaba)4(OH)2(DMF)6]·2(DMF)·1H2O (1) 1D coordination polymer. The single-crystal X-ray diffraction study reveals the formation of a neutral chain built from pentametallic complexes where each multi-polydentate ligand bridges four metal centres. The atypical morphology observed here for an oxamate-based 1D polymer arises from the use of a ligand bearing extra coordination sites. Magnetometry indicates strong dominating antiferromagnetic interactions within the polymer resulting in a non-zero ferrimagnetic state at low temperature.

Structure and properties of fluorinated and non‐fluorinated Ba‐coordination polymers – the position of fluorine makes the difference

AbstractAs the most electronegative element, fluorine has a strong influence on material properties such as absorption behaviour or chemical and thermal stability. Fluorine can be easily integrated into coordination polymers (CPs) via a fluorinated acetate, here trifluoroacetate in Ba(CF3COO)2, or directly via a metal fluorine bond (BaF(CH3COO)). In the present study both possibilities of fluorine integration were tested and their effect on structure and properties of barium coordination polymers was investigated in comparison with the non‐fluorinated barium acetate (Ba(CH3COO)2). In addition to the study of their thermal behaviour and their decomposition temperature, the CPs structures were tested for their application as possible anode materials in lithium ion batteries and for their sorption of water and ammonia. The properties of the CPs can be traced back to the individual structural motifs and could thus trigger new design ideas for CPs in LIBs and/or catalysis.

Investigating the Potential of Flexible and Pre-Organized Tetraamide Ligands to Encapsulate Anions in One-Dimensional Coordination Polymers: Synthesis, Spectroscopic Studies and Crystal Structures

The synthesis of amide-based molecules, possessing pre-organized structures, has received significant attention due to their potential applications as molecular receptors and as components of nanomaterials. In this study, four extended tetraamide ligands incorporating ethylene and propylene spacers, namely 1,2-bis[N,N′-6-(3-pyridylmethylamido)pyridyl-2-carboxyamido]ethane (L1), 1,2-bis[N,N′-6-(4-pyridylmethylamido)pyridyl-2-carboxyamido]ethane (L2), 1,2-bis[N,N′-6-(3-pyridylmethylamido)pyridyl-2-carboxyamido]propane (L3) and 1,2-bis[N,N′-6-(4-pyridylmethylamido)pyridyl-2-carboxyamido]propane (L4), were successfully synthesized. Further, reaction of L2 and L4, incorporating pendant 4-pyridyl donors as the metal coordinating sites, with cadmium salts, produced two close-packed one-dimensional coordination polymers, {[Cd3(L2)4(H2O)10](NO3)6·12H2O·CH3OH}n and {[Cd(SO4)(L4)(H2O)2]·4H2O·CH3OH}n. X-ray crystallography reveals that the flexible tetraamide ligands fold upon themselves in the coordination polymer structure. As a consequence, the anion pocket in {[Cd(SO4)(L4)(H2O)2]·4H2O·CH3OH}n incorporating the ligand with the propylene spacer was blocked from encapsulating charge-balancing anions, which were involved in bridging the di-cadmium units. Interestingly, a strong interaction between the 2,6-pyridine dicarboxamide moiety with the nitrate anions was found in {[Cd3(L2)4(H2O)10](NO3)6·12H2O·CH3OH}n, showing potential for materials made from these ligands to serve as anion receptors.

Solvothermal synthesis, structure and magnetic properties of heterometallic coordination polymers based on a phenolato-oxamato co-bidentate-tridentate ligand.

The use of solvothermal conditions has succesfully led to the preparation of heterometallic 1D coordination polymers from a co-bidentate-tridentate phenolato-oxamato ligand. The reaction of the N-(2-hydoxyphenyl)oxamic acid (ohpma) with acetate salts of transition metal ions at 80 °C has yielded the heterobimetallic [Cu(ohpma)M(OAc)(DMF)2] (M = Co (1); Mn (2)) and the heterotrimetallic [Cu(ohpma)Co0.57Mn0.43(OAc)(DMF)2] (3) chain compounds. Single-crystal and powder diffraction studies show that the polymers are isostructural. Magnetic studies suggest the existence of an inter-chain two-dimensional antiferromagnetic interaction taking place in compounds 1-3.

Copper nanoparticle anchored biguanidine-modified Zr-UiO-66 MOFs: a competent heterogeneous and reusable nanocatalyst in Buchwald-Hartwig and Ullmann type coupling reactions.

We have designed a functionalized metal–organic framework (MOF) of UiO topology as a support, with an extremely high surface area, adjustable pore sizes and stable crystalline coordination polymeric structure and implanted copper (Cu) nanoparticles thereon. The core three dimensional Zr-derived MOF (UiO-66-NH2) was modified with a biguanidine moiety following a covalent post-functionalization approach. The morphological and physicochemical features of the material were determined using analytical methods such as FT-IR, SEM, TEM, EDX, atomic mapping, XRD and ICP-OES. The SEM and XRD results justified the unaffected morphology of Zr-MOF after structural modifications. The as-synthesized UiO-66-biguanidine/Cu nanocomposite was catalytically explored in the aryl and heteroaryl Buchwald–Hartwig C–N and Ullmann type C–O cross coupling reactions with excellent yields. A library of biaryl amine and biaryl ethers was synthesized over the catalyst under mild and green conditions. Furthermore, the catalyst was isolated by centrifugation and recycled 11 times with no significant copper leaching or change in its activity.

Experimental and theoretical studies of a pyridylvinyl(benzoate) based coordination polymer structure

The electronic, adsorption and structural properties of a layered coordination polymer formed with 3,4-pvb− and copper(ii) were studied.

Anion‐Templated Self‐Assembly of Silver(I) Frameworks Bridged by μ‐, μ3‐, μ4‐1,2,4,5‐Tetrazine

The formation of Ag(I)‐1,2,4,5‐tetrazines(ttz) based coordination polymers via the Ag−N coordination and anion−π interactions is described. Coordination‐driven self‐assembly is a key step to construct coordination polymers, and ttz, an electron‐deficient aromatic ring compound, forms interesting anion−π interactions. In this study, a series of silver salts, AgX [X = BF4, PF6 and CF3SO3 (OTf)], is introduced to determine the influence of shape and size of anions on the formation of coordination polymers, {[Ag(ttz)](BF4)}n (1), {[Ag2(ttz)3](PF6)2}n (2) and {[Ag2(ttz)3(OTf)](OTf)}n (3). It shows different types of channels in polymers and the coordination modes of ttz (μ, μ3, and μ4). The structure of coordination polymers and the influence of anion−π interactions are revealed by single crystal X‐ray diffraction. In particular, 3 shows not only the anion−π interaction but also the coordination between the anion and Ag(I) which contributes to the unique framework compared to 1 and 2.

Synthesis, structure and gas adsorption properties of coordination polymers based on mixed imidazole-containing ligands and carboxylate ligands

Herein, we report the synthesis of two novel coordination polymers using a combination of imidazole-containing ligands, namely 1,3,5-tris((1H-imidazol-1-yl)methyl)benzene (L1) and 3,3′,5,5′-tetra(1H-imidazol-1-yl)-1,1′-biphenyl (L2) and a carboxylate ligand derived from 4,4′-biphenyldicarboxylic acid (H2BPDC). The structures of the two coordination polymers [Ni(L1)(BPDC)]·2H2O (1·2H2O), which exhibits a 2-fold interpenetrated 3D → 3D architecture, and {[Co(CH3OH)2(L2)0.5(BPDC)] (2) possessing a 2D framework, have been determined. Moreover, the gas adsorption properties of 1 and 2 have been investigated.

Synthesis, structures and fluorescent properties of two cadmium(II) coordination polymers based on bis(benzimidazole) and different anions

Two new Cd(II) coordination polymers (CPs), {[Cd(BBM)Cl2]·CH3OH}n (1) and [Cd2(BBM)2(isophthalate)2]n (2) (BBM = 2,2-(1,4-butanediyl)bis-1,3- benzimidazole), have been obtained from hydrothermal method and characterized by single-crystal X-ray diffraction, elemental analysis, IR and UV-Vis spectra. The CP 1 displays a one-dimensional (1D) square wave chain structure connected by BBM ligands, whereas CP 2 is a 2D layer network. The structure analysis revealed that the selection of anions with different coordination modes realizes the control of the structure of the cadmium coordination polymer. Weak hydrogen bonds and π···π interactions are the major driving forces in the crystal packing of the two coordination polymers. Hirshfeld surface analysis reveals detailed scrutiny of intermolecular interactions experienced by each complex. In addition, the fluorescence properties of the ligands and CPs 1-2 in the solid-state were studied. The fluorescence peaks of the two Cd(II) CPs were weakened compared to the free ligands, which is attributed to ligand-centered fluorescence. The partial quenching of the aggregates may be due to the π···π stacking and heavy atom effect.

Synthesis and structure of a bismuth-cobalt bimetal coordination polymer for green efficient photocatalytic degradation of organic wastes under visible light

A novel BiCo-based bimetal coordination polymer (BiCo-MCP) with a molecular formula Bi2Co2C42H36N6O33 was synthesized by a mild hydrothermal method. BiCo-MCP was characterized via single crystal X-ray diffraction, SEM and XRD. BiCo-MCP is crystallized in a two-dimensional structure. The energy gap of BiCo-MCP is ~1.65 eV, which indicates that this material can absorb light both in visible and UV regions. This work is the first report on photocatalytic degradation of pesticide by a bismuth-containing bimetallic coordination polymer. The multiplication effect of pH and H2O2 together with BiCo-MCP on the degradation of imidacloprid pesticide wastewater showed that the catalyst system with 1< pH <3.5 and H2O2 (0.18 × 10−3 mmol/L) give the best degradation rate of 81% comparing to 35.4%(BiCo-MCP) under visible light for 5 h. The most interesting feature is that using BiCo-MCP as catalyst for photocatalytic degradation of imidacloprid can obtain the final environmentally friendly inorganic species decreasing the possible formation of a variety of organic intermediates. The influences of different pH on BiCo-MCP as photocatalyst to degradation of Rhodamine B (RhB) has also been investigated indicating the enhanced degradation properties of RhB by BiCo-MCP in acidic or alkaline aqueous solution.

Synthesis and Crystal Structure of a Zinc Coordination Polymer Based on Bis(4-(2'-methylimidazol)phenyl)sulfone and (1,1'-Biphenyl)-2,2'-dicarboxylate Ligands

Zinc coordination polymer with V-shaped ligands, {[Zn(L1) ⋅ (bpda)] ⋅ H2O}n, (1) (L1 = bis(4-(2'-methylimidazol)phenyl)sulfone, H2bpda = (1,1'-biphenyl)-2,2'-dicarboxylic acid) was synthesized under solvothermal condition. The structure of 1 was determined by single-crystal X-ray diffraction analysis and further characterized by infrared spectra and elemental analyses. In 1, the Zn(II) ion is four-coordinated by two nitrogen atoms of two distinct L1 ligands and two oxygen atoms of two bpda2– to form a distorted tetrahedron. Complex 1 displays a 2D four-connected framework with a (65 × 8) topology along c direction.

Erratum to: Synthesis and Crystal Structure of a Cobalt Coordination Polymer Based on Bis(4-(1H-imidazol-1-YL)phenyl)methanone and trans-1,2-Cyclohexanedicarboxylate

erratum

Synthesis and crystal structure of new coordination polymers based on sodium aqua complexes and macrocyclic cavitand cucurbit[6]uril

The crystals of the compounds [Na4(H2O)14CB[6]](bdc)2 · 13H2O (1) and [Na6(H2O)19CB[6]]-(bdc)3 ·15H2O (2) were obtained by heating an aqueous solution of sodium terephthalate (Na2bdc) and cucurbit[6]uril (CB[6]). According to the single-crystal X-ray diffraction data, the sodium aqua complexes and cucurbit[6]uril molecules form chains (in structure 1) and layered metal-organic frameworks (in structure 2). The structures of the sodium aqua complexes [Na3(H2O)10]3+ in 1 and [Na6(H2O)19]3+ in 2 have been previously unknown. When submitted to ultraviolet radiation, crystals of 1 and 2 exhibit luminescence with an emission maximum at 428 and 434 nm, respectively.

Synthesis, molecular structure, spectroscopic characterization and antibacterial activity of the pyrazine magnesium porphyrin coordination polymer

A new material of magnesium(II) polymer compound with the formula {[MgII(TPP)(pz)]• 0.5[MgII(TPP)]•CH2Cl2}n (I), (TPP) = meso‑tetraphenylporphyrinato and pz = pyrazine) was synthetized and characterized by IR, UV-visible, PL photoluminescence and 1H NMR spectroscopy studies, single-crystal XRD analyses and cyclic voltammetry. The crystal structure of (I) is made by the 1D {[Mg(TPP)(pz)]} polymeric chains (molecules I(A)) where the tetracoordinated magnesium(II) complexes [Mg(TPP)] (molecules I(B)) are located as well as the dichloromethane solvent molecules. The crystal packing of (I) is stabilized by intermolecular CH⋯Cg π interactions where Cg is the centroid of phenyl and pyrrole rings. Additionally, the photophysical properties have been evaluated by UV-visible absorption and fluorescence emission spectroscopies. The UV-visible spectrum of (I) shows a redshift Soret band value (428 nm) compared to that of the free base H2TPP porphyrin while the λmax values of the Q bands are in the range 560 – 610 nm. The optical gap of (I) was estimated at 1.99 eV. The cyclic voltammogram of the title compound presents two reversible oxidation waves and one reversible reduction wave. The HOMO and LUMO energy values were deduced from the voltammogram which are -4.96 and -2.85 eV respectively. Furthermore, bioactivity investigations revealed that the free porphyrin, the starting material [MgII(TPP)] and complex (I) could be used as potential antibacterial agents.

Crystal Structures, Hirshfeld Surfaces, and Thermal Study of Isostructural Polymeric Ladders of La(III) and Sm(III) Coordination Compounds with 4,4'-Bipyridine and Dibromoacetates.

Two novel mixed ligand complexes with general formula [M2(4,4′-bpy)1.5(CBr2HCOO)6(H2O)2]n (where 4,4′-bpy = 4,4′-bipyridine) were synthesized. Thermal analysis was used to describe a solid intermediate and final products of thermolysis. A coupled TG-MS system was used to monitor principal volatile fragments evolved during pyrolysis. Crystal structures of the complexes were determined. Cationic dinuclear M2 (M(III) = La, Sm) coordination cores were obtained. Both crystal structures are isostructural. Single crystal X-ray diffraction analysis revealed that investigated structures of 1D coordination polymers assembled in ladder-like systems. The central atom replacement resulted in unit cell identity parameter П = 0.0091. Additionally, the isostructurality of the reported La(III) and Sm(III) complexes was revealed using Hirshfeld Surface analysis supported by Enrichment Ratio calculations.

Synthesis, crystal structure and photocatalytic property of a porphyrin-based coordination polymer

A new porphyrin-based coordination polymer, namely [Ni(TPPP)]n·nDMF (JLNU-100), has been rationally synthesized under solvothermal condition (H2TPPP = porphyrin-based ligand and DMF = N,N’-dimethylformamide). In JLNU-100, each Ni(II)-TPPP linker bridges two neighboring Ni(II) centers to afford a one-dimensional (1D) chain. These chains are further interlinked by C–H···π and π–π interactions to produce a 3D supramolecular architecture. The powder X-ray diffraction (PXRD) and UV-Vis diffuse-reflection spectrum (UV-Vis DRS) analyses reveal that JLNU-100 is stable and visible light responsible. Then, this material was used as an efficient photocatalyst for the degradation of methylene blue (MB) under visible light with a removal efficiency of 80.4%.

Synthesis, structure and properties of a 3D coordination polymer based on tetranuclear copper(I) and a tetra(triazole) ligand

A Cu(I) coordination polymer, {[Cu4Br(ttpe)3]Br2·(OH)}n (1), was prepared and characterized by single crystal X-ray diffraction analysis, EA, IR, PXRD, luminescence, optical band gaps and VB XPS spectra (ttpe = 1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene). 1 presents a two-fold interpenetrating (4,12)-connected 3D topology containing the [Cu4Br] tetranuclear copper(I) cluster building block with a point symbol of {44.62}3{424.640.82}. Eg, Ev and Ec of 1 were 2.20, 0.74 and −1.46 eV, respectively. 1 can act as a good photocatalyst for degradation of organic dyes. The photocatalytic mechanism was studied.