Showing papers on "Coordination polymer published in 2006"

A redox-active two-dimensional coordination polymer: preparation of silver and gold nanoparticles and crystal dynamics on guest removal.

Abstract: A two-dimensional (2D) square-grid coordination polymer, {[Ni(cyclam)]2[BPTC]}n·2nH2O (1), has been assembled from [Ni(cyclam)](ClO4)2 (cyclam = 1,4,8,11-tetraazacyclotetradecane) and H4BPTC (H4BPTC = 1,1‘-biphenyl-2,2‘,6,6‘-tetracarboxylic acid) in H2O/MeOH (2.5:1, v/v) in the presence of triethylamine. When solid 1 was immersed in the EtOH solutions of AgNO3 (1.3 × 10-1 M) and NaAuCl4·2H2O (3.4 × 10-2 M), respectively, for 5 min at room temperature, solids including Ag (3.7 ± 0.4 nm, diameter) and Au (2 nm, diameter) nanoparticles were formed by the redox reactions between Ni(II) ions incorporated in 1 and metal ions, as evidenced by HRTEM images, EPR, and XPS spectra. When single-crystal 1 was heated at 180 °C under 10-5 Torr for 24 h, it was transformed to dehydrated compound {[Ni(cyclam)]2[BPTC]}n (2) in the single-crystal-to-single-crystal manner. The X-ray crystal structure of 2 reveals extensive dynamic motions of the molecular components in response to guest removal, involving rotation of the car...

Influence of steric hindrance of organic ligand on the structure of Keggin-based coordination polymer

Abstract: Five Keggin-based 3D coordination polymers, namely, [Cu3(pz)3(PW12O40)] (pz = pyrazine) (1), [Cu3(2,3-Me2pz)3(PW12O40)] (2,3-Me2pz = 2,3-dimethylpyrazine) (2), [Cu2(2,5-Me2pz)1.5(2,5-HMe2pz)(PW12O40)] (2,5-Me2pz = 2,5-dimethylpyrazine) (3), [Cu3(2,3-Me2pz)3(PMo12O40)] (4), and [Ag3(pz)3(PW12O40)]·0.5H2O (5), were synthesized and structurally characterized. Crystal data are as follows: trigonal, space group R3c, a = 18.4070(14) A, c = 22.544(3) A, γ = 120°, and Z = 6 for 1; orthorhombic, space group Pccn, a = 16.599(2) A, b = 20.470(3) A, c = 14.3757(18) A, and Z = 4 for 2; triclinic, space group P1, a = 10.667(2) A, b = 11.147(2) A, c = 20.207(4) A, α = 90.983(4)°, β = 108.128(3)°, γ = 92.150(4)°, and Z = 2 for 3; orthorhombic, space group Pccn, a = 16.450(3) A, b = 20.170(4) A, c = 14.244(3) A, and Z = 4 for 4; and rhombohedral, space group R32, a = 18.2047(13) A, c = 23.637(3) A, γ = 120°, and Z = 6 for 5. Their structural differences were investigated using crystal structure analysis, revealing that...

Synthesis and characterization of metal-organic frameworks based on 4-hydroxypyridine-2,6-dicarboxylic acid and pyridine-2,6-dicarboxylic acid ligands.

Abstract: The self-assembly of 4-hydroxypyridine-2,6-dicarboxylic acid (H(3)CAM) and pyridine-2,6-dicarboxylic acid (H2PDA) with Zn(II) salts under hydrothermal conditions gave two novel coordination polymers {[Zn(HCAM)].H2O}n (1) and {[Zn(PDA)(H2O)(1.5)]}n (1a). 1 and 1a comprise of a 2D (4,4) net and a 1D zigzag chain, respectively, in which a new coordination mode of PDA is found. The reactions of H(3)CAM and H2PDA with Nd2O3 in the M/L ratio 2:3 gave {[Nd2(HCAM)3(H2O)4].2H2O}n (2) and {[Nd(2)(PDA)3(H2O)(3)].0.5H2O}n (2a). In 2, a square motif as a building block constructed by four Nd(III) ions was further assembled into a highly ordered 2D (4,4) grid. 2a is a 3D microporous coordination polymer. It is interesting to note that, when Ln(III) salts rather than oxides were employed, the reaction produced {[Ln(CAM)(H2O)3].H2O}n (Ln = Gd, 3; Dy, 4; Er, 5) for H(3)CAM and {[Gd2(PDA)3(H2O)3].H2O}n (3a) for H2PDA. 3-5 are 2D coordination polymers with a 3(3)4(2) uniform net, where hydroxyl groups of H3CAM coordinate with metal ions. The reaction of H3CAM and Er2O3 instead of Er(ClO4)3 produced {[Er2(HCAM)3(H2O)4].2H2O}n (6). The compounds 2a and 3a, 2 and 6 are isomorphous. The stereochemical and supramolecular effects of hydroxyl groups result in the dramatic structural changes from 1D (1a) to 2D (1) and from 2D (2) to 3D (2a). When Ln(III) salts instead of Ln2O3 were employed in the hydrothermal reactions with H(3)CAM, different self-assembly processes gave the products of different metal/ligand ratio with reactants (3-5).

Highly stable chiral cadmium 1,2,4-benzenetricarboxylate: synthesis, structure, and NLO and fluorescence properties.

Abstract: Employing an unsymmetrical 1,2,4-benzenetricarboxylate as a bridging ligand, a new 3-D chiral cadmium coordination polymer [Cd2(OH)(1,2,4-BTC)] (1,2,4-BTC = 1,2,4-benzenetricarboxylate) has been prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction. This compound crystallizes in the orthorhombic space group P212121, with cell parameters a = 6.900(2) A, b = 7.404(3) A, c = 19.116(5) A, V = 976.5(5) A3, and Z = 4. Its structure contains 2-D Cd−O−Cd connectivity, which is further linked by the 1,2,4-BTC ligand into a 3-D supramolecular framework. The 1,2,4-BTC ligand shows a novel and unprecedented coordination mode: nine bonds to eight metals with each carboxylate as a tridentate group. The compound exhibits intense photoluminescence at room temperature and shows distinct NLO properties. On the basis of the results of TG/DTA analyses, the structure is thermally stable up to ∼ 380 °C.

Loading of porous metal–organic open frameworks with organometallic CVD precursors: inclusion compounds of the type [LnM]a@MOF-5

Abstract: The highly porous coordination polymer [Zn4O(bdc)3] (bdc = benzene-1,4-dicarboxylate; MOF-5 or IRMOF-1) was loaded with typical MOCVD precursor molecules 1–10 for metals such as Fe, Pt, Pd, Au, Cu, Zn, Sn. Exposure of [Zn4O(bdc)3] to the vapour of the volatile organometallic compounds, e.g. ferrocene (3), resulted in the formation of inclusion compounds of the type [LnM]a@MOF-5, where [LnM] indicates the MOCVD precursor and a denotes the effective number of molecules per cavity of the MOF-5 lattice. The obtained inclusion compounds were characterised by C/H combustion analysis, determination of the metal content by atomic absorption spectroscopy, FT-IR and solid state NMR spectroscopy and by powder X-ray diffraction. The data prove that the host lattice and the guest molecules interact only by weak van der Waals forces without any change of the framework or the chemical nature of the included molecules. Rapid desorption is observed for small and comparably volatile compounds such as pentacarbonyliron or diethyl zinc. Less labile inclusion compounds were obtained for cyclopentadienyl complexes as guest molecules, e.g. a rather high loading of six molecules of ferrocene per cavity was observed. Careful hydrolysis/calcination of [Zn(C2H5)2]2@MOF-5 resulted in the composite (ZnO)2@MOF-5 pointing to the possibility to develop a subsequent chemistry of the embedded precursor molecules to yield novel nanocomposite materials based on MOFs as host matrices and MOCVD precursors in general.

Immobilization of sodium ions on the pore surface of a porous coordination polymer.

Abstract: A porous coordination polymer (PCP) with immobilization of sodium cations on the pore surface has been synthesized, by employing a bifunctional carboxylate/sulfonate ligand, and structurally characterized. The porous framework with 1D channels of the dimension of 4.9 × 4.9 A2 shows high thermal stability (∼330 °C), affording Type I adsorption isotherms for CO2, acetone, and benzene. The chemical shift of 13C NMR and characteristic adsorption energy (βE0) of acetone adsorbed in this compound represent the Lewis acidity of this framework.

Self-Assembly of Extended High-Dimensional Architectures from Anderson-type Polyoxometalate Clusters

Abstract: Three unusual compounds based on polyoxometalate building blocks, [(C6H5NO2)2Ln(H2O)4]2[IMo6O24][NO3]·4H2O (Ln = Ce 1 and La 2) and [(H2O)4Ag3][Cr(OH)6Mo6O18]·3H2O 3, have been synthesized and characterized by elemental analysis, IR and X-ray photoelectron spectroscopy, thermogravimetry analysis, and single-crystal X-ray diffraction. Compounds 1 and 2 are isostructural and possess a unique two-dimensional (2D) network, which is composed of rare earth coordination polymer chains joint together by [IMo6O24]5- polyoxoanions, representing the first example of 2D inorganic−organic hybrid compounds based on A-type Anderson polyoxoanions. Compound 3 is constructed from B-type Anderson polyoxoanions [Cr(OH)6Mo6O18]3- and silver (I) ions to yield a three-dimensional (3D) open framework containing “guest” water molecules. To our best knowledge, it is the first time Anderson-type polyoxometalate motifs have been connected with silver ions to construct a 3D covalent framework.

Synthesis and structure of a stable pentavalent-uranyl coordination polymer.

Abstract: The polymeric complex {[UO2Py5][KI2Py2]}n was isolated by controlled oxidation of uranium tris-iodide in pyridine and structurally characterized using X-ray diffraction. The described synthetic method allows us to isolate a stable derivative of the elusive pentavalent UO2+ species providing a potential starting material for the development of anhydrous UO2+ coordination chemistry.

TCNQ Dianion-Based Coordination Polymer Whose Open Framework Shows Charge-Transfer Type Guest Inclusion

Abstract: A three-dimensional coordination framework constructed with 7,7,8,8-tetracyano-p-quinodimethane (TCNQ) diainon has been synthesized and structurally characterized. This open framework possessing a highly electron-rich surface has an optical sensing cavity for several aromatics with crystal-to-crystal transformation and strong accommodation, which are based on a charge-transfer interaction with them.

A Polar Luminescent Zn Polymer Containing an Unusual Noninterpenetrated utp Net

Abstract: A new Zn coordination polymer with the mixed ligands of 1,3,5-benzenetricarboxylate and 1,3-bis(4-pyridyl)propane has been hydrothermally synthesized, and an unusual distorted noninterpenetrated utp [or (10,3)-d] net has been defined.

A robust microporous 3D cobalt(II) coordination polymer with new magnetically frustrated 2D lattices: single-crystal transformation and guest modulation of cooperative magnetic properties

Abstract: A microporous 3D cobalt(II) coordination polymer featuring pillared layers [Co2(ma)(ina)]n·2nH2O (1·2H2O) (ma = malate, ina = isonicotinate) was generated by hydrothermal treatment with a void volume of 25.8%, in which the in-situ generated ma ligands connect the CoII ions into a 2D lattice with mixed and multiple exchange-bridges, affording a new geometrical topology different from the Kagome lattice and leading to spin frustration. The rigid ina-pillared metallic-layered structure could retain 3D structural ordering upon guest removal and exchange. By soaking guest-free host (1) in MeOH and methanamide (HCONH2) solutions, single crystals of dehydrated 1 were transformed into single crystals of 1·MeOH and 1·HCONH2, respectively, without apparent host-structural changes. 1 can also be rehydrated into 1·2H2O′. The guest-inclusion crystals have been characterized by X-ray single-crystal diffraction at 293 K and 93 K, confirming the single-crystal-to-single-crystal transformations and providing detailed information of the guest molecules confined in the subnanospace and host–guest and/or guest–guest hydrogen-bonding interactions. The magnetic behaviours of this family of porous magnetic materials are complex due to the influences of multiple metal sites, intra- and inter-layer exchanges, spin–orbit coupling, as well as geometrical frustration, which show magnetic ordering at <2 K, 3.5 K, 3.5 K, and 8 K for 1, 1·MeOH, 1·HCONH2, and 1·2H2O, respectively, due to the different size of guest molecules along with the different host–guest interaction, which may slightly modify the path of magnetic exchange, decrease the intensity of the spin-frustration in the 2D lattice, and cooperatively enhance the magnetic ordering temperature.

Synthesis and Characterization of a 3D Coordination Polymer Based on Trinuclear Triangular CuII as Secondary Building Units

Abstract: The hydrothermal reaction of CuII salts with 1,2,4-triazole (Htrz) in aqueous ammonia yielded a novel metal−organic framework {[Cu3(μ3-O)(μ3-trz)3(OH)(H2O)6]}n (1), which was characterized by single-crystal X-ray diffraction, X-ray powder diffraction, thermogravimetric analysis, IR, and variable-temperature magnetic susceptibility. It crystallizes in cubic, space group Fd3c with a = 24.644(3) A, V = 14967(3) A3, and Z = 96. Its framework is the first 3D structure using coordinative interactions constructed via trinuclear triangular CuII secondary building units, in which both CuII ions and trz ligands act as three-connected nodes to form a 6.82 net. An overall antiferromagnetic behavior was found in the compound.

First metal azide complex with isonicotinate as a bridging ligand showing new net topology: hydrothermal synthesis, structure, and magnetic properties.

Abstract: A new 3D azido-bridged coordination polymer, [Co15(N3)(OH)(Isonic)]n (1), has been synthesized and characterized and its magnetic properties studied Isonicotinate acts as a bridging coligand in this complex In 1, all of the ligands take tridentate bridging coordination modes, and the overall structure of 1 exhibits a new 3,6-connected net topology

Metal-Controlled Assembly of Coordination Polymers with the Flexible Ligand 1,1‘-Biphenyl-2,2‘-dicarboxylate Acid

Abstract: To determine the influence of metal ions on the formation of metal−organic frameworks, five new coordination polymers, [Pb6(dpa)4O2]n (1), [Ag2(dpa)]n (2), [Nd2(dpa)3(H2O)2]n (3), [Zn(dpa)(H2O)]n (4), and [Cd2(dpa)2(phen)2(H2O)2]n (5), have been hydrothermally synthesized from 1,1‘-biphenyl-2,2‘-dicarboxylate acid (dpa). Complex 1 is a one-dimensional chain structure constructed from a new building unit, Pb6O18, which is connected by four different dpa molecules. Complex 3 is also a one-dimensional chain structure but is composed of a different building unit bridged by three dpa molecules. This complex is further extended into a two-dimensional supramolecular framework. Like complex 3, complex 4 is a two-dimensional supramolecular framework, which is connected by one-dimensional chains through π−π interactions and hydrogen bonding interactions. Complex 5 is a three-dimensional metal−organic supramolecular coordination polymer that possesses rectangular cavities. Different from the above four complexes, co...

Supermolecular Architecture of a Polypseudo-rotaxane: [Cd(BPE)(α-Mo8O26)][Cd(BPE)(DMF)4]·2DMF (BPE = 1,2-Bis(4-pyridyl)ethane, DMF = N,N-Dimethylformamide)

Abstract: An unprecedented polyoxometalate-containing coordination polymer, [Cd(BPE)(α-Mo8O26)][Cd(BPE)(DMF)4]·2DMF (BPE = 1,2-bis(4-pyridyl)ethane, DMF = N,N-dimethylformamide), which comprises one-dimensional chains penetrating two-dimensional networks, is synthesized and characterized.

An Aqua-Soluble Copper(II)−Sodium Two-Dimensional Coordination Polymer with Intercalated Infinite Chains of Decameric Water Clusters

Abstract: Self-assembly synthesis in water, at room temperature, with dinuclear copper triethanolaminate and aqua−sodium building blocks as well as benzene-1,2,4,5-tetracarboxylate linkers leads to the formation of an heteronuclear Cu−Na assembly with a two-dimensional metal−organic framework, providing the first example of an aqua-soluble copper-containing coordination polymer that hosts infinite chains of decameric water clusters (H2O)10 formed by quasiplanar cyclic water octamers with two pendent water molecules.

Frontiers in crystal engineering

Abstract: List of Contributors. Foreword. 1. Applications of Crystal Engineering Strategies in Solvent-free Reactions: Toward a Supramolecular Green Chemistry. 1 Introduction. 1 Mechanochemical preparation of Hydrogen-Bonded Adducts. 1 Mechanically induced formation of covalent bonds. 1 The solvent-free chemistry of the zwitterion. 1 Concluding remarks. 1 Acknowledgements. References. 2. Crystal Engineering of Pharmaceutical Co-crystals. 1 Introduction. 2 What is the origin of polymorphism and is it prevalent in co-crystals?. 3 What is the pharmaceutical co-crystal?. 4 Conclusions. 5 Acknowledgements. References. 3. Template-controlled Solid-state Synthesis: Toward a General Form of Covalent Capture in Molecular Solids. 1 Introduction. 2 Controlling reactivity using linear templates. 3 Template-controlled solid-state reactivity. 4 Target-oriented organic synthesis in the organic state. 5 Other linear templates. 6 Summary and outlook. References. 4. Interplay of Non-covalent Bonds: Effect of Crystal Structure on Molecular Structure. 1 Introduction. 2 Second-sphere coordination. 3 Soft coordination environments. 4 Speciation. 5 Molecular conformation. 6 Conclusions. References. 5. Crystal Engineering of Halogenated Heteroaromatic Clathrate Systems. 1 Introduction. 2 Aromatic edge-edge C-H...N dimers. 3 Heteroatom-1,3-peri interactions. 4 Molecular pen structures. 5 Halogenated edge-edge interactions. 6 Pi-halogen dimer (PHD) interactions. 7 Molecular bricks, spheres and grids. 8 Conclusions. 9 Acknowledgements. References. 6. Steric Control over Supramolecular Aggregation: A Design Element in Crystal Engineering? 1 Introduction. 2 Diorganotin carboxylates. 3 Triorganotin carboxylates. 4 Binary zinc xanthates. 5 Bipyridine adducts of zinc dithiophosphates. 6 Binary mercury dithiocarbamates. 7 Binary bismuth xanthates. 8 Conclusions and Outlook. 9 Acknowledgements. References. 7. Incorporating Molecular Hosts into Network Structures. 1 Introduction. 2 Hydrogen-bonded structures with CTV. 3 Coordination polymers. 4 Extended-arm CTV derivatives and their coordination polymers. 5 Conclusions. 6 Acknowledgements. References. 8. Interpenetrating Networks. 1 Introduction. 2 Notation. 3 1-D nets. 4 2-D nets. 5 3-D nets. 6 Unusual interpenetration. 7 Consequences of interpenetration. 8 Self-penetration. 9 Entangled but not interpenetrating. 10 Conclusions. References. 9. Architecture and Functional Engineering Based on Paddlewheel Dinuclear Tetracarboxylate Building Blocks. 1 Introduction. 2 Synthetic strategy. 3 Architecture engineering based on preorganized building blocks. 4 Conductive and magnetic properties based on preorganized building blocks. 5 Porous properties based on preorganized and in situ building blocks. 6 Conclusion and outlook. References. 10. Supramolecular Interactions in Directing and Sustaining Coordination Molecular Architectures. 1 Introduction. 2 Molecular architectures assembled by hydrogen-bonding interactions. 3 Molecular architectures assembled VIA ... Interactions. 4 Metallophilic interactions. 5 Concluding remarks and outlooks. 6 Acknowledgements. References. 11. The Structure-directing Influence of Hydrogen Bonding in Coordination Polymers. 1 Introduction. 2 A novel cadmium cyanide network. 3 Dihydroxybenzoquinone and Chloranilic acid derivatives of Lanthanides. 4 A stable zinc saccharate network. 5 Anionic metal-carbonate networks. 6 Conclusions. References. 12. Hydrogen-bonded Coordination Polymeric Structures. 1 Introduction. 2 Solid-state supramolecular transformation of hydrogen-bonded 3-D network to 3-D coordination polymetric network structures by thermal dehydration. 3 Interconvertible solid-state supramolecular transformation. 4 Solid-state transformation of a helical coordination polymetric structure to a 3-D coordination network structure by thermal dehydration. 5 Influence of chiral centers on the helicity of the coordination polymers. 6 Consequences of C=O... interactions. 7 Supramolecular isomerism. 8 Starlike channels and hexagonal diamondoid topology. 9 Hydrogen-bonded helical water molecules inside a staircase 1-D coordination polymer. 10 Hydrogen-bonded polyrotaxane-like structure containing cyclic (H2O)4 in [Zn(OAc)2(m-bpe)].2H2O. 11 Summary. 12 Acknowledgements. References. Index.

A Novel Chiral Cd(II) Coordination Polymer Based on Achiral Unsymmetrical 3-Amino-1,2,4-triazole with an Unprecedented μ4-Bridging Mode

Abstract: A novel chiral cadmium coordination polymer, Cd(AmTAZ)Cl (AmTAZH = 3-amino-1,2,4-triazole), has been solvothermally synthesized and structurally characterized by IR, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. This compound crystallizes in the chiral space group P212121 with a = 6.4126(5), b = 7.8307(9), c = 10.4658(10) A, V = 525.54(9) A3, and Z = 4. Interestingly, the amino group of the AmTAZ ligand is also coordinated to a cadmium ion besides three other N atoms of the triazolate ring, which “locks” the asymmetry of the AmTAZ and may transfer this asymmetry throughout the crystal structure to “direct” the formation of a chiral network. The structure possesses a unique three-dimensional open-framework and contains two different types of helical channels with left- and right-handed character presented alternately along the c-axis. The compound exhibits second-order nonlinear optical (NLO) activity, intense blue fluorescent emission, and high thermal stability.

Syntheses, Structures, and Photoluminescence of Three Novel Coordination Polymers Constructed from Dimeric d10 Metal Units

Abstract: Three novel coordination polymers containing dimeric d10 metal units, [Cd(2,3-Pydc)(H2O)2]n (1), [Zn(2,3-Pydc)(H2O)2]n (2), and {[La2Zn3(2,3-Pydc)6(H2O)6]·4H2O}n (3), have been synthesized by hydrothermal reaction of pyridine-2,3-dicarboxylic acid (2,3-Pydc) with d10 metal oxides at a suitable temperature. Complex 1 is a one-dimensional (1D) ladder coordination polymer containing a dimeric Cd2O8N2 unit. Complex 2 forms a two-dimensional (2D) layer built from a unique Zn2O8N2 unit, in which each pair of Zn(II) ions are bridged by two water molecules. Complex 3 is a 2D heterometallic framework by 1D chain linked by Zn(2,3-Pydc) units, where the 1D chain is constructed via dimeric La2O16 units. The photoluminescent studies show that complex 2 illustrates an emission at 417 nm (λex = 363 nm).

Reversible formation of polymeric chains by coordination of pentaphosphaferrocene with silver(I) cations.

Abstract: A fragile coordination polymer: The pentaphosphaferrocene [Cp*Fe(5-P5)] reacts with the AgI salt of the weakly coordinating anion [Al{OC(CF3)3}4]- to yield a polymer comprising cyclo-P5 moieties in an unprecedented 1,2,3-coordination mode (see figure). Analytical data and DFT calculations support the existence of a monomer/dimer/oligomer equilibrium in solution, which is entirely in favor of the monomer at room temperature and shifts to the dimer/oligomer at reduced temperatures.

Ionic Liquid as Solvent for the Synthesis and Crystallization of a Coordination Polymer: (EMI)[Cd(BTC)] (EMI = 1-Ethyl-3-methylimidazolium, BTC = 1,3,5-Benzenetricarboxylate)

Abstract: An ionic liquid, 1-ethyl-3-methylimidazolium bromide, is used as reaction medium for the synthesis and crystallization of a coordination polymer, (EMI)[Cd(BTC)] (1) (EMI = 1-ethyl-3-methylimidazolium, BTC = 1,3,5-benzenetricarboxylate), which forms an anionic three-dimensional framework with 1-ethyl-3-methylimidazolium cations located in the void space.

Molecular and multidimensional organic-inorganic hybrids based on polyoxometalates and copper coordination polymer with mixed 4,4'-bipyridine and 2,2'-bipyridine ligands

Abstract: Three novel organic−inorganic hybrid materials with mixed 4,4‘-bipyridine and 2,2‘-bipyridine ligands, K[{CuI(2,2‘-bipy)}(4,4‘-bipy){CuI(2,2‘-bipy)}0.5]2[Mo8O26] (1), [CuI(4,4‘-bipy)]3[PMo10VIMo2VO40{CuII(2,2‘-bipy)}] (2), and [CuI(2,2‘-bipy)(4,4‘-bipy)0.5]2[CuI(4,4‘-bipy)]2[SiW12O40] (3) (2,2‘-bipy = 2,2‘-bipyridine, 4,4‘-bipy = 4,4‘-bipyridine), have been hydrothermally synthesized. Compound 1 is a novel β-[Mo8O26]4- polyoxoanion bisupported by copper(I) coordination cations with mixed 4,4‘-bipy and 2,2‘-bipy ligands. Compound 2 consists of the divalent copper {CuII(2,2‘-bipy)}2+ capped [PMo10VIMo2VO40]5- building blocks linked by {Cu(4,4‘-bipy)}nn+ linear cationic chains into a novel two-dimensional (2D) network. To the best of our knowledge, compound 2 exhibits an unprecedented 2D structure containing the divalent copper capped polyoxometalate as building blocks. The novel structure of 3 is composed of one-dimensional hybrid zigzag chains linked by {Cu(4,4‘-bipy)}nn+ chains into a three-dimensional (3...

Nitro-functionalization and luminescence quantum yield of Eu(III) and Tb(III) benzoic acid complexes

Abstract: In our pursuit of luminescent lanthanide ion-based coordination polymers, we have isolated several complexes with nitrobenzoic acid ligands and characterized these by X-ray crystallography and luminescence spectroscopy. 2-Nitrobenzoic acid reacts with Eu(III) to form 1, which crystallizes in the P-1 space group, with a = 12.385(3), b = 12.912(3), c = 17.889(4) A, α = 97.49(3), β = 109.64(3) and γ = 101.99(3)°. 3-Nitrobenzoic acid forms a one-dimensional coordination polymer with Eu(III), 2, which crystallizes in the triclinic space group P-1 with a = 9.7100(19), b = 10.579(2), c = 13.361(3) A, α = 77.41(3), β = 88.78(3) and γ = 88.16(3)°. Structures 3 and 4 correspond to the isostructural one-dimensional coordination polymers of Eu(III) and Tb(III), respectively, with the 4-nitrobenzoato anion. These crystallize in the triclinic space group P-1 with a = 9.2242(18), b = 15.102(3), c = 18.587(4) A, α = 75.93(3), β = 82.88(3) and γ = 79.00(3)° for 3 and a = 9.2692(19), b = 15.369(3), c = 18.353(4) A, α = 75.37(3), β = 81.32(3) and γ = 78.15(3)° for 4. Potentiometry, absorption and NMR spectroscopy indicate that in solution only 1 : 1 species are present. All compounds are weakly luminescent as solids and the photophysics of solutions of ligands with Ln(III) in 1 : 1 stoichiometry were studied. Quantum yields around 1 and 3% for Eu(III)-and Tb(III)-containing methanolic solutions were measured.