Carboxylate Coordination Polymers Research Articles

Polymorphism and Structural Variety in Sn(II) Carboxylate Coordination Polymers Revealed from Structure Solution of Microcrystals.

The crystal structures of four coordination polymers constructed from Sn(II) and polydentate carboxylate ligands are reported. All are prepared under hydrothermal conditions in KOH or LiOH solutions (either water or methanol-water) at 130-180°C and crystallize as small crystals, microns or less in size. Single-crystal structure solution and refinement are performed using synchrotron X-ray diffraction for two materials and using 3D electron diffraction (3DED) for the others. Sn2 (1,3,5-BTC)(OH), where 1,3,5-BTC is benzene-1,3,5-tricarboxylate, is a new polymorph of this composition and has a three-dimensionally connected structure with potential for porosity. Sn(H-1,3,5-BTC) retains a partially protonated ligand and has a 1D chain structure bound by hydrogen bonding via ─COOH groups. Sn(H-1,2,4-BTC) contains an isomeric ligand, benzene-1,2,4-tricarboxylate, and contains inorganic chains in a layered structure held by hydrogen bonding. Sn2 (DOBDC), where DOBDC is 2,5-dioxido-benzene-1,4-dicarboxylate, is a new polymorph for this composition and has a three-dimensionally connected structure where both carboxylate and oxido groups bind to the tin centers to create a dense network with dimers of tin. In all materials, the Sn centers are found in highly asymmetric coordination, as expected for Sn(II). For all materials phase purity of the bulk is confirmed using powder X-ray diffraction, thermogravimetric analysis, and infrared spectroscopy.

Retraction Note to: Two Novel Ca(II)-Carboxylate Coordination Polymers: Crystal Structures and Antimyeloma Activity Evaluation

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1134/S0022476623040194

An Interesting Conversion Route of Mononuclear Zinc Complex to Zinc Mixed Carboxylate Coordination Polymer.

A complex [Zn(bpy)(acr)2]·H2O (1) was converted in a DMF medium (DMF = N,N'-dimethylformamide) into a coordination polymer [Zn(bpy)(acr)(HCOO)]n (1a) (bpy = 2,2'-bipyridine, and Hacr = acrylic acid), and the species was fully characterized through a single crystal X-ray diffraction. Additional data were obtained by IR and thermogravimetric analysis. Complex (1a) crystalized the coordination polymer in the space group Pca21 of an orthorhombic system. Structural characterization revealed that Zn(II) adopted a square pyramidal stereochemistry generated by bpy molecules, coordinated by chelate, acrylate, and formate ions as unidentate and bridged, respectively. The presence of both the formate and the acrylate with different coordination modes generated two bands in ranges that were characteristic for the carboxylate vibration modes. Thermal decomposition occurs in two complex steps: it first happens via a bpy release, which is followed by an overlapped process that is associated with acrylate and formate decomposition. The obtained complex is of present interest due to the presence of two different carboxylates in its composition and situation, which is rarely reported in the literature.

Zinc(II) Carboxylate Coordination Polymers with Versatile Applications.

This review considers the applications of Zn(II) carboxylate-based coordination polymers (Zn-CBCPs), such as sensors, catalysts, species with potential in infections and cancers treatment, as well as storage and drug-carrier materials. The nature of organic luminophores, especially both the rigid carboxylate and the ancillary N-donor bridging ligand, together with the alignment in Zn-CBCPs and their intermolecular interaction modulate the luminescence properties and allow the sensing of a variety of inorganic and organic pollutants. The ability of Zn(II) to act as a good Lewis acid allowed the involvement of Zn-CBCPs either in dye elimination from wastewater through photocatalysis or in pathogenic microorganism or tumor inhibition. In addition, the pores developed inside of the network provided the possibility for some species to store gaseous or liquid molecules, as well as to deliver some drugs for improved treatment.

Hydrated proton conduction and luminescence of a carboxylate and sulfonate-included lead(II) coordination polymer

A Pb(II)-based coordination polymer, namely Pb-BSDC, has been synthesized by the reaction of 2,2′-bis(sulfomethyl)-[1,1′-biphenyl]-4,4′-dicarboxylic acid (H4BSDC) and lead nitrate through solvothermal self-assembly strategy. With the protophilic sulfonic groups and hydrogen-bonding interactions, Pb-BSDC exhibits efficient water-assisted proton conduction. Importantly, single-crystal Pb-BSDC shows a high proton conductivity of 1.71 ​× ​10-2 ​S ​m-1 at 90 ​°C and 85% RH (relative humidity), suggesting a promising candidate for proton-conductor. Further mechanism investigation indicates that proton conduction in bulk sample of Pb-BSDC follows the Vehicle mechanism (Ea ​= ​0.63 ​eV) while single-crystal state follows the Grotthuss mechanism (Ea ​= ​0.35 ​eV). In addition, the luminescent property of Pb-BSDC was also studied and it showed a broad band emission with the maximum at 502 ​nm under the irradiation of 310 ​nm UV light.

A Zirconium Indazole Carboxylate Coordination Polymer as an Efficient Catalyst for Dehydrogenation‐Cyclization and Oxidative Coupling Reactions

AbstractRational ligand design is crucial for achieving widespread applications of coordination polymers. The preparation, structural characterisation, and catalytic applications of zirconium (IV) coordination polymer (Zr‐IDA), which was derived from 1‐(carboxymethyl)‐1H‐indazole‐5‐carboxylic acid are reported. The Zr‐IDA catalyst contains porous and highly crystalline particles with a quasi‐spherical morphology around 100 nm in size, and Zr was coordinated with both O and N as shown by FT‐IR and XPS measurements. Importantly, the Zr‐IDA catalyst shows great activity, selectivity and stability in the oxidative coupling of benzyl cyanides with tert‐butyl hydroperoxide to afford tert‐butyl peresters, and the dehydrogenation cyclization of o‐phenylenediamines with aromatic alcohols to afford 1,2‐disubstituted benzimidazole derivatives. Mechanistic investigations were carried out to study these reactions and the developed catalytic system in more detail.

Hydrogen bonding-tuned hydroxo-bridged tetra-copper Cu4(bipy)4-cluster supramolecular network to layered coordination polymer

Hydrogen bonds influence the transformation of the Cu4-cluster⋯ligand hydrogen net to the layered coordination polymer.

Two novel Ca(II)-carboxylate coordination polymers: Crystal structures and antimyeloma activity evaluation

In this study, two new coordination polymers [Ca3(BTB)2(NMP)2(H2O)2](NMP)(H2O)4 (1, H3BTB = benzene-1,3,5-tribenzoic acid, NMP = N-methyl-pyrrolidone) and [Ca3(NTB)2(DEF)2(H2O)2](DEF)(H2O)4 (2, H3NTB = 4,4',4''-nitrilotribenzoic acid, DEF = N,N-diethyl-formamide) based on the alkaline earth metal Ca(II) ion and two rigid C3-symmetric tricarboxylic acid ligands are successfully prepared via the solvothermal reaction. The structural analysis of complexes 1 and 2 demonstrates the existence of different topologies and structures in the as-prepared complexes because of the conformational flexibility of the organic ligands and the diverse geometry of the Ca(II)-based 1D secondary building unit. The particle sizes of these two complexes could be conveniently downsized in nanometer region via a simple treatment. In addition, in vitro anticancer activity of compounds 1 and 2 in nanometer has been studied for inhibition human myeloma cell growth via the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay.

Structural diversity of a series of terpyridyl carboxylate coordination polymers: Luminescent sensor and magnetic properties

Eleven new coordination polymers, [Zn2(ctpy)2(HCOO)2]n·3nH2O (1), [Zn2(ctpy)2(HCOO)2(H2O)2]n·nH2O (2), [Zn2(ctpy)2(H2O)4]n·2n(CH3COO)·nH2O (3), [Zn2(ctpy)2(CH3COO)2]n·nH2O (4), [Zn(ctpy)2]n·nH2O (5), [Zn2(ctpy)2(Hidc)(H2O)2]n(6), [Cd2(ctpy)4]n(7), [Cd2(ctpy)2(Hidc)]n(8), [Co2(ctpy)2(HCOO)2(H2O)2]n·nH2O (9), [Co(ctpy)(DMF)(ox)0.5]n(10), [Co(ctpy)(ox)0.5]n(11) and the closely related compound [Zn(ctpy)(ox)0.5]n·0.5nH2O (12) (Hctpy = 4′-carboxy-4,2′:6′,4′′-terpyridine, H2ox = oxalic acid and H3idc = imidazole-4,5-dicarboxylic acid) have been synthesized by hydro(solvo)thermal reaction of 4′-carboxy-4,2′:6′,4′′-terpyridine with divalent metal salts and characterized by elemental analysis, IR spectra, single crystal X-ray diffraction. Compounds 1 and 4 have similar structure which demonstrate a two-fold interpenetrating 3D framework with a 3-connected utp topological net, which contains the same number of left and right-handed 21 helical chains. Compounds 2 and 9 are isostructural 2D layer with a 3-connected hcb topological net. Similar to 2, compound 3 also displays a 3-connected 2D hcb topological net. Compounds 5 and 10 are a 2D layer with a 4-connected sql topological net. Compound 6 shows a chiral 2D layer based on a 1D left- or right-handed helical chains, which are further extended into an achiral 2D + 2D→3D supramolecular network by hydrogen bonds with alternately arrangement. Compound 7 features an unusual 2-fold interpenetrating 3D coordination network which exhibits a new intriguing (3,5)-connected binodal topological net with the Schläfli symbol of (52·6)(53·63·73·8). Compound 8 shows a 2D→3D supramolecular structure based on (3,4)-connected 2D bilayers with the Schläfli symbol of (44·62). Compound 11 displays an unusual three-dimensional coordination network which exhibits an intriguing (3,8)-connected binodal new topological net with Schläfli symbol (42·62)2(42·623·83). Compound 12 features a two-fold interpenetrating (3,4)-connected 3D framework with the fsc topological net. Compounds 1–12 were obtained under similar reaction conditions. The diverse structures indicate that rational selection of the second ligand, metal salt, counter anion and solvent are good methods to further design metal-organic compounds with new structures and properties. Moreover, their thermal stabilities, photoluminescent and magnetic properties were also investigated. More importantly, compound 12 has been successfully applied in the detection of Fe3+ ion in DMF solutions and nitrobenzene and the possible detecting mechanism was also discussed.

Lithium carboxylate coordination polymers based on trimesic acid

Three new metal-organic coordination polymers (H2NMe2)2[Li3(btc)(Hbtc)(DMF)4] (1), [Li5(DMF)6(btc)(Hbtc)]·2DMF (2), and [Li6(DMF)8(bdc)(Hbtc)] (3) (H3btc is trimesic acid, H2bdc is terephthalic acid) are prepared by heating LiOH with different aromatic carboxylic acids in dimethyl formamide (or its mixture with water). The crystal structures and composition of the compounds are determined by single crystal X-ray diffraction. Compound 1 has a layered structure; compounds 2 and 3 have a framework structure.

Synthesis and structural elucidation of 1-D silver(I) aliphatic carboxylate coordination polymers with 1,3,5-triaza-7-phosphaadamantane/N-methyl-1,3,5-triaza-7-phosphaadamantane

Reactions of silver(I) salts of acetate and trifluoroacetate with 1,3,5-triaza-7-phosphaadamantane (PTA) afforded 1-D coordination polymers [Ag(μ2-PTA-κ2P -:N)(μ2-O2CCH3-κ2O:O′)]n·2nH2O (1) and [Ag(μ2-PTA-κ2P:N)(μ2-O2CCF3-κO)]n·nH2O (2), while a reaction of silver(I)trifluoroacetate with N-methyl-1,3,5-triaza-7-phosphaadamantane (PTAMe) afforded the coordination polymer [Ag(PTAMe)(μ3-O2CCF3-κ3O:O:O’)(μ2-O2CCF3-κ2O:O′)]n (3). The coordination polymers were characterized using single-crystal X-ray diffraction. Nuclear magnetic resonance, infrared, and electron spray ionization mass spectrometries were used to initially establish complexation of Ag(I) to the PTA or PTAMe before recrystallization. In the crystal structures of 1 and 2, coordination of the PTA moieties to Ag(I) is via P and N forming chains that are linked through bridging carboxylates. The resulting structural motif can be described as ladder-like in which –[PTA–Ag–PTA]– chains are the strands while the bridging carboxylates comprising of –[Ag–O–C–O]2– or –[Ag–O]2– metallacycle rungs of the ladder. Compound 3 forms single-stranded coil-like coordination polymers with two non-equivalent Ag(I) centers, both tetrahedrally coordinated by four oxygens from four trifluoroacetates in one and by three oxygens from the trifluoroacetates and in each by the P of the PTAMe with alternating Ag⋯Ag interactions. The crystal structures of all three coordination polymers have a variety of fairly strong hydrogen bonds and intermolecular interactions which contribute stabilization of the crystal lattices.

Four lanthanide–carboxylate coordination polymers with mixed 2,3-naphthalenedicarboxylate and phen ligands: Syntheses, structures, luminescent and magnetic properties

Four new lanthanide–carboxylate coordination polymers of the formula [Ln3L4(phen)4(H2O)4](ClO4)·2H2O, (Ln=Dy (1), Tb (2), Ho (3) and Er (4), L=2,3-naphthalenedicarboxylate and phen=1,10-phenanthroline) were solvothermally synthesized. Their structures as well as magnetic and photoluminescent properties were completely investigated. Complexes 1–4 are isostructural and exhibit 1D ribbon-like chains with envelope-like sixteen-membered rings. The DyIII and TbIII complexes show the corresponding characteristic luminescence in the visible region and the ErIII complex shows luminescence in the near-infrared region upon excitation with UV rays. Studies on the magnetic properties are reported. The Dy(III) analog complex 1 exhibits slow magnetic relaxation and could be a new example of a Dy(III) SMM (single molecule magnet).

ChemInform Abstract: Transition Metal Carboxylate Coordination Polymers with Amide‐Bridged Polypyridine Co‐Ligands: Assemblies and Properties

AbstractReview: 90 refs.

Core-double-shell Fe3O4@carbon@poly(In(III)-carboxylate) microspheres: cycloaddition of CO2 and epoxides on coordination polymer shells constituted by imidazolium-derived Al(III)-Salen bifunctional catalysts.

A hydrid microsphere Fe3O4@carbon@poly(In(III)-carboxylate) consisting of a cluster of Fe3O4 nanoparticles as the core, a carbon layer as the inner shell and a porous In(III)-carboxylate coordination polymer as the outer shell was prepared and applied as a recyclable catalyst for the cycloaddition reaction of CO2 and epoxides. Construction of this hybrid microsphere was achieved in the two steps, including (1) the one-pot solvothermal synthesis of Fe3O4@C particles with the abundant carboxylic groups on the carbon surface and (2) the subsequent growth of the outer shell polymers based on the precipitation coordination polymerization. Imidazolium-substituted Salen ligands were synthesized and chelated with the In(III) ions using the terminal carboxylic groups. The coordination polymer shell was formed on the Fe3O4@C particles, and the structures including shell thickness, surface area and porosity could be varied by tuning the feeding ratios of the In(III) ions and the ligands. The optimal structure of the coordination polymers showed a shell thickness of ca. 45 nm with ∼5 nm of mesopore, 174.7 m(2)/g of surface area and 0.2175 cm(3)/g of pore volume. In light of gas uptake capability, catalytic activity and magnetic susceptibility, cycloaddition of CO2 with a series of epoxides were studied by using Al-complexed Fe3O4@C@In(III)-[IL-Salen] microspheres. The results validated that the self-supporting catalytic layer with high surface area was of remarkable advantages, which were attributed from great increment of effective active sites and combination of nucleophilic/electrophilic synergistic property and CO2 uptake capability. Therefore, these hybrid microspheres provided excellent catalytic activity, prominent selectivity to cyclic carbonates and outstanding recyclability with the assistance of an applied magnetic field.

Transition metal carboxylate coordination polymers with amide-bridged polypyridine co-ligands: assemblies and properties

Coordination polymers (CPs) can be formed by the self-assembly of metal ions and one kind of ligand or mixed ligands. Carboxylate anions have been extensively utilized to construct metal–organic CPs with diverse structures and topologies as well as versatile properties. The introduction of neutral nitrogen-donor co-ligands in such metal carboxylate system is an effective strategy for tuning the architectures and functionalities of metal–organic CPs. As a family of neutral nitrogen-donor co-ligands, amide-bridged polypyridine compounds have been introduced into such metal carboxylate system in the past decade. A large number of metal–organic CPs derived from the mixed ligands of carboxylate and amide-bridged polypyridine have been reported. Therefore, we present the recent developments of transition metal carboxylate CPs with amide-bridged polypyridine co-ligands in this highlight. We summarize their syntheses, structures, architectural influence factors and properties in detail. Such highlight may play a significant role in the rational design and construction of amide-bridged polypyridine-based transition metal carboxylate CPs with structure-dependent properties.

ChemInform Abstract: An Introduction to Synthesis and Application of Nanoscale Metal‐Carboxylate Coordination Polymers

AbstractReview: 107 refs.

An introduction to synthesis and application of nanoscale metal–carboxylate coordination polymers

In recent years, nanoscale metal–organic coordination polymers have attracted more and more attention because of their specific properties in gas sorption, sensors, contrast agents, drug delivery, templates and so on. Carboxylate compounds are a large family of O-donor ligands and are studied widely because such ligands can be designed with various structures and can also form strong bonds with metal centers. Until now, many nanoscale metal–organic coordination polymers with carboxylate-containing ligands have been reported. The purpose of this tutorial highlight is to present recent advances in the syntheses of nanoscale metal–carboxylate coordination polymers and illustrate the potential application of this new class of nanomaterials in different areas.

Synthesis and Luminescent Properties of a Novel Nanoscale Eu(III)-Carboxylate Coordination Polymer

To prepare nanoscale coordination polymers (NCPs) which can exhibit intense luminescence have attract an increasing interest. In this paper, we present the synthesis of a novel example of discus-like luminescent nanoscale Eu (III)-carboxylate coordination polymers. The organic ligand is a derivative of terephthalate (Na2L) with a big side group. The Eu (III)-L NCPs was synthesized through microemulsion method, and the morphology can alter along with the changing of metal: ligand ratios. XRD results reveal that the self-assembled disk-like NCPs exhibit long-range ordered structures. The luminescent measurements showed that the resultant NCPs not only exhibits typical fluorescence of Eu (III), but also can maintain the inherent fluorescence of the ligands.

Solid state syntheses of nano lead(II) iodide triazole carboxylate coordination polymer from its bromide/thiocyanate/chloride analogs via mechanochemical crystal to crystal transformations

Irreversible crystal-to-crystal transformations of 3D lead(II) coordination polymers with the ligand 1H-1,2,4-triazole-3-carboxylic acid (HL), [Pb(L)(μ2-Br)(H2O)]n (1), [Pb(L)(μ1,1-NCS)(H2O)]n (2) and [Pb(L)(μ2-Cl)(H2O)]n (3) to 3D supramolecular compound [Pb(L)(μ2-I)]n (4) by solid state anion-replacement processes under mechanochemical reactions, have been studied. The thermal stabilities of compounds 1–4 were studied by thermogravimetric and differential thermal analyses. The irreversible solid state structural transformations of compounds 1–4, by anion-replacement processes under mechanochemical reaction, have been verified by PXRD measurements. Nanoparticles of compounds 1 and 2 were synthesized by sonochemical process and characterized by scanning electron microscopy (SEM), powder X-ray diffraction, IR spectroscopy, elemental analyses, thermogravimetric and differential thermal analyses. The SEM images showed that no morphology change occurs during solid state anion-replacements of nanocrystals.

Synthesis, Structures, and Luminescent Properties of Uranyl Terpyridine Aromatic Carboxylate Coordination Polymers

Six novel uranyl terpyridine aromatic carboxylate coordination polymers, [UO(2)(C(6)H(2)O(4)S)(C(15)H(11)N(3))] (1), [UO(2)(C(6)H(2)O(4)S)(C(15)H(10)N(3)Cl)]·H(2)O (2), [UO(2)(C(8)H(4)O(4))(C(15)H(11)N(3))] (3), [UO(2)(C(8)H(4)O(4))(C(15)H(10)N(3)Cl)] (4), [UO(2)(C(12)H(6)O(4))(C(15)H(11)N(3))] (5), and [UO(2)(C(12)H(6)O(4))(C(15)H(10)N(3)Cl)] (6), were synthesized under solvothermal conditions and characterized by single-crystal and powder X-ray diffraction and luminescence and UV-vis spectroscopy. Compounds 1, 2, and 5 crystallize as molecular uranyl dimers, whereas compounds 3, 4, and 6 contain ladder motifs of uranyl centers. Fluorescence spectra of 1-4 show characteristic UO(2)(2+) emission, wherein bathochromic and hypsochromic shifts are noted as a function of organic species. In contrast, uranyl emission from 5 and 6 is quenched by the naphthalene dicarboxylic acid linker molecules.