A series of two‐dimensional lanthanide coordination polymers: synthesis,structures, magnetism and selective luminescence detection for heavy metal ions and toxic solvents

A series of two‐dimensional (2D) coordination polymers (CPs), namely poly[[bis(μ‐acetato)diaqua(μ₆‐biphenyl‐3,3′,5,5′‐tetracarboxylato)bis(N,N‐dimethylacetamide)digadolinium(III)] N,N‐dimethylacetamide monosolvate], {[Gd₂(C₁₆H₆O₈)(C₂H₃O₂)₂(C₄H₉NO)₂(H₂O)₂]·C₄H₉NO}_n ( CP1 ), poly[[bis(μ‐acetato)diaqua(μ₆‐biphenyl‐3,3′,5,5′‐tetracarboxylato)bis(N,N‐dimethylacetamide)didysprosium(III)] N,N‐dimethylacetamide monosolvate], {[Dy₂(C₁₆H₆O₈)(C₂H₃O₂)₂(C₄H₉NO)₂(H₂O)₂]·C₄H₉NO}_n ( CP2 ), poly[bis(μ‐acetato)diaqua(μ₆‐biphenyl‐3,3′,5,5′‐tetracarboxylato)bis(N,N‐dimethylacetamide)dineodymium(III)], [Nd₂(C₁₆H₆O₈)(C₂H₃O₂)₂(C₄H₉NO)₂(H₂O)₂]_n ( CP3 ), poly[bis(μ‐acetato)diaqua(μ₆‐biphenyl‐3,3′,5,5′‐tetracarboxylato)bis(N,N‐dimethylacetamide)disamarium(III)], [Sm₂(C₁₆H₆O₈)(C₂H₃O₂)₂(C₄H₉NO)₂(H₂O)₂]_n ( CP4 ), has been synthesized from rigid biphenyl‐3,3′,5,5′‐tetracarboxylic acid under solvothermal conditions. Their structures have been determined by single‐crystal X‐ray diffraction analyses, elemental analyses, IR spectra, powder X‐ray diffraction and thermogravimetric analyses, and CP1 – CP4 crystallize in the monoclinic space group P2₁/n. CP1 – CP4 are isomorphous and feature similar 2D double layers, which are further extended via interlayer hydrogen‐bonding interactions into a three‐dimensional (3D) supramolecular structure. Hydrogen‐bonding interactions between N,N‐dimethylacetamide molecules and carboxylate O atoms strengthen the packing of the layers. The organic ligands interconnect with metal ions to generate 2D layered structures with a (4,4)‐connected net having {4⁴.6²} topology. CP1 has been investigated for its magnetic properties and magnetic susceptibility measurements were carried out in the range 2.0–300 K. The results of the magnetic measurements show weak antiferromagnetic coupling between the Gd^III ions in CP1 . Moreover, the strong luminescence of CP2 and CP4 can be selectively quenched by the Fe³⁺ ion and toxic solvents (e.g. acetone).     

Two manganese(II) coordination polymers driven by (iso)nicotinoyl-hydrazone blocks and pseudohalide ancillary ligands: syntheses,structural features,and magnetic properties

Two coordination polymers, [Mn₂(μ-L¹)₂(μ-N₃)₂]_n (1) and [Mn(μ-HL²)(SCN)₂]_n (2), were assembled in a single-pot from MnCl₂·4H₂O, HL¹ (2-acetylpyridine isonicotinoylhydrazone) or HL² (2-acetylpyridine nicotinoylhydrazone) and ancillary ligand sources (NaN₃ or NH₄NCS). The products were fully characterized, including by single-crystal X-ray diffraction, which revealed a 2-D metal–organic layer in 1 and a 1-D zigzag coordination chain in 2. Both 1 and 2 are constructed from six-coordinate Mn(II) nodes that adopt distorted octahedral (MnN₅O) environments; the adjacent nodes are driven by the μ-L¹ and μ-N₃ linkers in 1 or μ-HL² linkers in 2 to form different metal–organic networks. Their topological classification was performed, disclosing the hcb and 2C1 topology in 1 and 2, respectively. Different weak non-covalent interactions promote dimensionality extension. Variable-temperature magnetic susceptibility measurements were carried out, revealing weak ferromagnetic and antiferromagnetic interactions in 1 and 2, respectively.     

Solvent-dependent structural diversity of cadmium(II) coordination polymers: syntheses,characterizations, and luminescence properties

By changing the solvent, three cadmium(II) coordination polymers (CPs), [Cd(NH₂-BDC)(DMA)(H₂O)]_n (1), {[Cd(NH₂-BDC)₂(DMF)₂]·H₂O}_n (2) and {[(Me₂NH₂)₂Cd₂(NH₂-BDC)₃(H₂O)]·DMF·8H₂O}_n (3), have been synthesized based on the V-shaped linker 5-aminoisophthalic acid and Cd(NO₃)₂·4H₂O under the same reaction temperature (140 °C) (NH₂-BDC = 5-aminoisophthalate, DMA = N,N-dimethylacetamide, DMF = N,N-dimethylformamide). Compound 1 features a 1-D ladder-like infinite chain. Compound 2 is a 2-D (4,4) net when the dinuclear [Cd₂(COO)₄O₄] is regarded as a quadruply-connected node. Compound 3 shows a 2-D hamburger-like structure. Luminescent properties of 1–3 were detected at room temperature under the same excitation and emission wavelengths of 200–600 nm with the same interval of 5 nm. Moreover, the calculation of lattice constants and volumes, and density of states of CPs 1 and 2 were carried out to get better insight into the nature of the structure and luminescence.     

Syntheses,structures, and photoluminescence of three cadmium(II) coordination polymers with flexible bis(benzimidazole) ligands

Three cadmium(II) coordination polymers, [CdBr₂(L₁)] _n (1), [CdI₂(L₂)] _n (2), and Cd₂Br₄(L₃)₂ (3), where L₁?=?1,3-bis(5,6-dimethylbenzimidazole)propane, L₂?=?1,4-bis(5,6-dimethylbenzimidazole)butane, and L₃?=?1,6-bis(5,6-dimethylbenzimidazole)hexane, have been synthesized by hydrothermal methods and characterized by elemental analyses, IR spectra, TGA, PXRD, and X-ray crystallographic diffraction. Complex 1 contains a 1-D helical chain in which CdBr₂ units are linked by L₁. For 2, each CdI₂ is connected by two different conformations of L₂ to form a 1-D zigzag chain. For 3, each CdBr₂ is linked by L₃ bridges to afford a binuclear structure. These results indicate that the spacer length of the ligands play important roles in assembly of Cd(II) coordination polymers. Thermogravimetric analyses and solid-state luminescent properties of the complexes have also been investigated.     

Hydrothermal synthesis,crystal structures,and photoluminescent properties of two cadmium(II) coordination polymers derived from dicarboxylates and N-donor ligands

Two metal coordination polymers, [Cd(ipa)(L₁)(H₂O)]_n (1) and [Cd(ipa)(L₂)]_n (2) [H₂ipa?=?isophthalic acid, L₁?=?3,5-bis(imidazole-1-yl)pyridine and L₂?=?3,5-bis(benzoimidazo-1-ly)pyridine], have been synthesized and structurally characterized by IR, elemental analysis, XRD, and X-ray single-crystal diffraction. Complex 1 shows a twofold cds topological net and 2 features a 3-D pcu topological net. Luminescent properties of 1 and 2 were investigated in the solid state at room temperature.     

Synthesis,structures, and properties of a series of similar structural coordination polymers with triphosphonate anions as ligands

The hydrothermal reactions of metal precursors with aminotri(methylenephosphonic acid) yielded a series of similar structural coordination polymers of general formula {M[HN(CH₂PO₃H)₃](H₂O)₃}_n [M = Mg(II) (1), Mn(II) (2), Co(II) (3), Zn(II) (4) and Cd(II) (5)]. Compounds 1–5 were characterized by X-ray single crystal diffraction, elemental analyses, and thermogravimetric analyses. Compounds 1–5 all reveal the wave-like 1D chain structures and the structures are constructed by two types of eight-membered, square-like rings linked alternatively via the phosphonate oxygen atoms, generating double-channel systems. The magnetic studies of 2 and 3 reveal that antiferromagnetic interactions are mediated between the metal ions.     

Cu(II) coordination polymers stabilized by pyridine-2,6-dicarboxylate anion and pyrazole derivatives through ligand hydrolysis

Abstract

2,6-Pyridinedicarbonyldichloride (PDD) was treated with pyrazole, 3-methylpyrazole, and 3,5-dimethylpyrazole in the presence of trimethylamine at room temperature. Reactions afforded 2,6-bis(pyrazolyl-1-carbonyl)pyridine (1), 2,6-bis(3-methylpyrazolyl-1-carbonyl)pyridine (2) and 2,6-bis(3,5-dimethylpyrazolyl-1-carbonyl)pyridine (3). 1-3 were treated with copper ion under ambient conditions in open air. Such coupling of 1 and 2 with copper led to coordination polymers 6 and 7, bearing 1D architectures, of general formulas [Cu(C₇H₃NO₄)(C₃H₄N₂)]_n and [Cu(C₇H₃NO₄)(C₄H₇N₂)]_n (C₇H₃NO₄?=?2,6-pyridinedicarboxylate ion, C₃H₄N₂?=?pyrazole and C₄H₇N₂?=?3-methylpyrazole), respectively. Under the same experimental conditions, 3 instead forms a mononuclear Cu(II) complex (8). Structures of 1-3 and 6-8 were determined with X-ray diffraction. The solid state structures reveal that short-range intermolecular interactions in the ligands afford 1D (1) and 2D (2 and 3) supramolecular chains, respectively. 6 and 7 both crystallize in the orthorhombic system, space group P2₁2₁2₁. 1–3 were also characterized with elemental analysis and NMR spectroscopy. The magnetic susceptibility measurements indicate that both complexes are paramagnetic with effective moments of 1.75 (6) and 1.90 (7) µ_B at 300 K. The voltammetric signatures of 6 and 8 show two steps reversible redox behavior as evidenced by the appearance of two cathodic waves with corresponding anodic peaks in the backward scan.     

A new basic motif in cyanometallate coordination polymers: structure and magnetic behavior of M(mu-OH2)2[Au(CN)2]2 (M=Cu, Ni)

The structures of two cyanoaurate-based coordination polymers, M(mu-OH(2))(2)[Au(CN)(2)](2) (M=Cu, Ni), were determined by using a combination of powder and single-crystal X-ray diffraction techniques. The basic structural motif for both polymers contains rarely observed M(mu-OH(2))(2)M double aqua-bridges, which generate an infinite chain; two trans [Au(CN)(2)](-) units also dangle from each metal center. The chains form ribbons that interact three dimensionally through CNH hydrogen bonding. The magnetic properties of both compounds and of the dehydrated analogue Cu[Au(CN)(2)](2) were investigated by direct current (dc) and alternating current (ac) magnetometry; muon spin-relaxation data was also obtained to probe their magnetic properties in zero-field. In M(mu-OH(2))(2)[Au(CN)(2)](2), ferromagnetic chains of M(mu-OH(2))(2)M are present below 20 K. Interchain magnetic interactions mediated through hydrogen bonding, involving water and cyanoaurate units, yield a long-range magnetically ordered system in Cu(mu-OH(2))(2)[Au(CN)(2)](2) below 0.20 K, as indicated by precession in the muon spin polarization decay. Ni(mu-OH(2))(2)[Au(CN)(2)](2) undergoes a transition to a spin-glass state in zero-field at 3.6 K, as indicated by a combination of muon spin-relaxation and ac-susceptibility data. This transition is probably due to competing interactions that lead to spin frustration. A phase transition to a paramagnetic state is possible for Ni(mu-OH(2))(2)[Au(CN)(2)](2) upon application of an external field; the critical field was determined to be 700 Oe at 1.8 K. The dehydrated compound Cu[Au(CN)(2)](2) shows weak antiferromagnetic interactions at low temperatures.     

Crystal structure and fluorescence/phosphorescence of two novel Cd(II) coordination polymers

Two novel Cd(II) coordination polymers [Cd₄(C₆H₄O₂N)₈(H₂O)₄]_n (1) and [Cd₂(C₁₀H₂O₈)(H₂O)₆]_n (2) have been synthesized under hydrothermal condition and structurally characterized. Crystal data: (1), orthorhombic, Pbca, a=11.4494(19) Å, b=12.0969(6) Å, c=17.4073(8) Å, V=2410.9(4) ų, Z=8, D _calc=2.064 g·cm⁻³; (2), triclinic, P , a=5.5962(7) Å, b=7.7758(6) Å, c=9.6975(10) Å, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, V=371.95(7) ų, Z=2, D _calc=2.603 g·cm⁻³. Complex (1) possesses three-dimensional infinite structure, while complex (2) adopts two-dimensional layers and the layers are connected by the many types of hydrogen bonds, forming three-dimensional network. Study results of the photophysical properties show that both complexes can emit strong blue fluorescence and complex (1) also emits phosphorescence (λ ^pl _max=511 nm, τ=32 ms) in the solid state at room temperature.     

Syntheses,structures, and fluorescent properties of two uranium coordination polymers with carboxylic acids

Two U(VI)-containing coordination polymers, (UO₂)₂O₂(Suc)(2,2′-bipy)₂ (1) and UO₂(BC)₂(DMF) (2) (2,2′-bipy?=?2,2′-bipyridine, H₂Suc?=?succinic acid, HBC?=?benzoic acid, DMF?=?N,N-dimethylformamide), have been synthesized and characterized via elemental analysis, infrared spectroscopy, UV-Vis spectroscopy, and single-crystal X-ray diffraction. Structural analyses show that 1 is a 1-D chain coordination polymer in which U(VI) ions are connected by succinic acid ligand and the 1-D chain is connected into a 3-D supramolecular network by C?H···O hydrogen bonds between carbon of 2,2′-bipyridine and uranyl oxygen. For 2, monomeric entities are further assembled into a 1-D supramolecular network by C–H···O hydrogen bonds between carbon of DMF molecule and coordinated carboxylate oxygen. Thermogravimetric analyses and photoluminescent properties of 1 and 2 are discussed.     

Highly efficient pure white polymer light-emitting devices based on poly(N-vinylcarbazole) doped with blue and red phosphorescent dyes

Efficient white-polymer-light-emitting devices (WPLEDs) have been fabricated with a single emitting layer containing a hole-transporting host polymer,poly(N-vinylcarbzole),and an electron-transporting auxiliary,1,3-bis[(4-tert-butylphenyl)-1,3,4-oxadiazolyl]-phenylene,codoped with two phosphorescent dyes:Iridium(III)bis (2-(4,6-difluorophenyl)-pyridinato-N,C2') picolinate (FIrpic) and home-made Ir-G2 for blue and red emission,respectively.With the structure of ITO/PEDOT:PSS 4083(40 nm)/emission layer(80 nm)...     

Synthesis,spectral and thermal studies on pyrazolatebridged palladium(II) coordination polymers

Synthesis, spectroscopic characterization and thermal behavior of pyrazolate-bridged palladium complexes [Pd(μ-Pz)₂]_n (1), [Pd(μ-mPz)₂]_n (2), [Pd(μ-dmPz)₂]_n (3), [Pd(μ-IPz)₂]_n (4) {pyrazolate (Pz^–), 4-methylpyrazolate (mPz^–), 3,5-dimethylpyrazolate (dmPz^–), 4-iodopyrazolate (IPz^–)} have been described in this work. The exobidentate coordination mode of pyrazolato ligands in 1–4 was inferred on basis of IR spectroscopic evidences. TG investigations indicated that the introduction of substituents at the 4 position in the pyrazolyl moiety into coordination polymers do not affect significantly their thermal stability, whereas at the 3 and 5 position reduced the stability of the main chain. Metal palladium was the final product of the thermal decompositions, which was identified by X-ray powder diffraction.     

Syntheses and characterizations of nine coordination polymers of transition metals with carboxylate anions and bis(imidazole) ligands

Nine new compounds, namely [CuL1(biim-6)] · H₂O (1), [ZnL1(biim-6)] · H₂O (2), [MnL1(biim-6)] · H₂O (3), [MnL1(biim-4)] (4), [Co₂(L2)₂(biim-5)₃ · 6H₂O] · 8H₂O (5), [ZnL3(biim-6)] (6), [ZnL3(biim-5)] (7), [CdL3(biim-5) · 1.5H₂O] · 0.5H₂O (8) and [CdL4(biim-6) · 2H₂O] (9) [where L1 = oxalate anion, L2 = fumarate anion, L3 = phthalate anion, L4 = p-phthalate anion, biim-4 = 1,1′-(1,4-butanediyl)bis(imidazole), biim-5 = 1,1′-(1,5-pentanedidyl)bis(imidazole) and biim-6 = 1,1′-(1,6-hexanedidyl)bis(imidazole)] were successfully synthesized. Compounds 1–3 are isostructural, and display 2D polymeric structures. Compound 4 shows a threefold interpenetrating diamondoid framework. In compound 5, the anions act as counterions, and the metal cations are bridged by bis(imidazole) ligands to form 1D polymeric chains. Compounds 6–9 show 2D polymeric structures. The magnetic properties for 1, 3 and 4 and luminescent properties for 2 and 6–9 are discussed. Thermogravimetric analyses (TGA) for these compounds are also discussed.     

基于双咪唑和二元羧酸配体的配位聚合物的合成、表征和发光性质研究

利用水热法合成了2种新的双咪唑及二元羧酸配体镉配合物[Cd(sdc)(bipe)]·H_2O(1)和[Cd(bpdc)(bipe)(H_2O)](2)[bipe=bis(4-imidazolphenoxy)ethane,H_2sdc=4,4’-sulfonyldibenzoic acid,H_2bpdc=biphenyl-4,4’-dicarboxylic acid].通过元素分析、红外光谱(IR)、X射线单晶衍射和热重分析(TG)等方法对其进行表征,并测试了2种化合物的荧光性质.化合物1展示了一个具有{4~4·6~2}拓扑的(4,4)-连接的sql二维空间网络结构,配体与金属间荷移跃迁化合物2显示了一个具有(4~(12)·6~3)的六连接pcu网状拓扑结构.荧光测试结果显示,配体与金属间发生的荷移跃迁使得化合物1和2的荧光发射峰与配体bipe相比明显发生了红移.     

Formation of 1 D and 3 D coordination polymers in the solid state induced by mechanochemical and annealing treatments: bis(3-cyano-pentane-2,4-dionato) metal complexes

Bis(3-cyano-pentane-2,4-dionato) (CNacac) metal complex, [M(CNacac)(2)], which acts as both a metal-ion-like and a ligand-like building unit, forms supramolecular structures by self-assembly. Co-grinding of the metal acetates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with CNacacH formed a CNacac complex in all cases: mononuclear complex was formed in the cases of Mn(II), Cu(II) and Zn(II), whereas polymeric ones were formed in the cases of Fe(II), Co(II) and Ni(II). Subsequent annealing converted the mononuclear complexes of Mn(II), Cu(II) and Zn(II) to their corresponding polymers as a result of dehydration of the mononuclear complexes. The resultant Mn(II), Fe(II), Co(II), Ni(II) and Zn(II) polymeric complexes had a common 3 D structure with high thermal stability. In the case of Cu(II), a 1 D polymer was obtained. The Mn(II), Cu(II) and Zn(II) polymeric complexes returned to their original mononuclear complexes on exposure to water vapour but they reverted to the polymeric complexes by re-annealing. Co-grinding of metal chlorides with CNacacH and annealing of the mononuclear CNacac complexes prepared from solution reactions were also examined for comparison. [Mn(CNacac)(2)(H(2)O)(2)], [M(CNacac)(2)(H(2)O)] (M=Cu(II) and Zn(II)) and [M(CNacac)(2)](infinity) (M=Mn(II), Fe(II) and Zn(II)) are new compounds, which clearly indicated the power of the combined mechanochemical/annealing method for the synthesis of varied metal coordination complexes.     

Synthesis, crystal structures and fluorescence properties of four mixed-ligands Zn(Ⅱ) and Cd(Ⅱ) coordination compounds

Four new coordination compounds, [Zn(dba)(bpy)]n (1), {[Zn(dba)(phen)]·2H2O}n (2), [Cd(dba)(bpy)(H2O)2] (3) and [Cd2(dba)2(phen)2]n (4) (H2dba = 2,5-dihydroxy-p-benzenediacetic acid, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline) have been prepared via solvothermal method and characterized by sin-gle-crystal X-ray diffraction, infrared spectroscopy, elemental analysis and powder X-ray diffraction. 1 and 2 possess 1D infinite chain structures. Complex 3 exhibits a mononuclear structure. Complex 4 owns bi...     

Zinc coordination polymers with rigid dicarboxylates and semirigid 3,5-bis(imidazole-1-yl) pyridine: syntheses,structural topologies,and luminescent properties

Two metal coordination polymers, {[Zn(bpdc)(bip)]·2H₂O}_n (1) and [Zn(tdc)(bip)] (2) [H₂bpdc?=?biphenyl-4,4’-dicarboxylate, H₂tdc?=?thiophene-2,5-dicarboxylate, bip?=?3,5-bis(imidazole-1-yl)pyridine], have been synthesized and characterized by IR, elemental analysis, XRD, and X-ray single-crystal diffraction. In 1, bpdc and bip link Zn(II) ions into a corrugated 2D layer. The corrugated 2D layers polycatenate each other, yielding a 2D→3D polycatenation net. In 2, dinuclear Zn(II) units are formed by bip and further connected by tdc to construct a 2D 3-connected framework. The luminescent properties of 1 and 2 are investigated in the solid state at room temperature.     

Crystalline complexes,coordination polymers and aggregation modes of tetra(4-pyridyl)porphyrin

Aggregation patterns of tetra(4-pyridyl)porphyrin and of its zinc(II) complex in seven new solid materials have been investigated by X-ray diffraction. The metalloporphyrin compound forms two types of coordination polymers through ligation of the porphyrin periphery on one molecule to the metal center of an adjacent porphyrin. These include one-dimensional chains with a zigzag conformation, as well as three-dimensional, extensively interlinked, polymeric structures. The non-metallated compound reveals a characteristic layered arrangement and interporphyrin stacking of the type which is commonly observed in the structures of tetraphenylporphyrin derivatives. In the absence of a metal center, the basic functionality of the pyridyl substituents is utilized for effective H-bond directed coordination and co-crystallization with solvent/guest components. The stoichiometry of the porphyrin solvation, and the consequent interporphyrin organization in the solid phase, are quite sensitive to the nature of the coordinating solvent.Author for correspondence. Supplementary Data relating to this article are deposited with the British Library as supplementary publication No. SUP 82174 (37 pages).     

Two new Pb(II) coordination polymers derived from fatty dicarboxylates and phenanthroline derivatives: syntheses,structures, and properties

Two new Pb(II) coordination polymers, [Pb(3-pdip)(L₁)]?·?0.5H₂O (1) and [Pb(4-pdip)(L₂)] (2) [L₁?=?heptane diacid, L₂?=?hexane diacid, 3-pdip?=?2?-(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline, 4-pdip?=?2?-(4-pyridyl)imidazo[4,5-f]1,10-phenanthroline], have been obtained from hydrothermal reactions of Pb(II) nitrate with two flexible fatty carboxylic acids and two phenanthroline derivatives. Single-crystal X-ray diffraction analysis reveals that 1 is a 1-D staircase-like double chain coordination polymer extended by binuclear [Pb₂N₄O₈] subunits and pairs of L₁ ligands. Compound 2 exhibits a 2-D (4,4) network based on bi-metallic [Pb₂N₆O₈] units and (L₂)₂/(4-pdip)₂ double linkers. Furthermore, adjacent chains of 1 and layers of 2 are extended into 3-D supramolecular networks by π–π stacking interactions between aromatic rings of phenanthroline groups. The organic carboxylic acids with different lengths show great influence on the shapes of Pb(II)-carboxylate double chains. Phenanthroline derivatives possessing different sites of N-donors (3-pyridyl and 4-pyridyl) determine the final coordination frameworks of 1 and 2. Photoluminescence and thermal stabilities of 1 and 2 were also investigated.