Microwave-assisted synthesis,crystal structure and toxicity of <Emphasis Type="Italic">L</Emphasis>-aspartic acid zinc spiral linear supramolecular polymer

L-aspartic acid zinc was synthesized by a rapid and convenient method in high yield under microwave conditions, and its single crystal structure was analyzed by X-ray diffraction. The structure unit of the title compound is [Zn(L-Asp)(H₂O)₂]·H₂O, which is a bicyclo-complex forming a spiral linear polymer via coordination bonds. The spiral linear polymers are assembled as a three-dimensional supramolecule by intermolecular hydrogen bonds. The crystal belongs to the orthorhombic crystal system, P2(1)2(1)2(1) space group, a=0.7830(3) nm, b=0.9369(4) nm, c=11.599(5) nm, α=β=γ=90.00°, V=0.8509(6) nm³, Z=4, Dc=1.955 g/cm³, F(000)=512, μ=2.289. The toxicity of the title compound is lower than that of glutamic acid zinc and zinc sulfate.     

Preparation and surface modification of magnetic poly(methyl methacrylate) microspheres

~~Preparation and surface modification of magnetic poly(methyl methacrylate) microspheres~~     

Synthesis,spectral, crystal structural,antimicrobial, DNA interaction and thermal behavior of some new zinc halide complexes: 3D supramolecular structure of zinc bromide complex

Three new four coordinated zinc(II) complexes have been synthesized and characterized by IR, UV, elemental analysis, ¹H and ¹³C NMR and X-ray single crystal analysis. The elemental analyses of the complexes are in agreement with the general formula of ZnLX₂ wherein L = Schiff base ligand and X = Cl^?, Br^? and I^?. Low molar conductivities in DMF indicated non-electrolyte character of all complexes. Spectroscopic studies well confirmed the coordination via azomethine nitrogens of the ligand to zinc ion. The single crystal X-ray analysis shows that ZnLBr₂ crystallizes in the triclinic crystal system with space group $\mathit{P}\overline{1}$. It contains two crystallographically independent molecules noted as A and B, with both Zn1A and Zn1B being almost in perfect tetrahedral environments (τ₄ = 0.94 for Zn1A and τ₄ = 0.93 for Zn1B). A detailed structural analysis shows that there are three non-classical hydrogen bondings of C–H…Br in the structure. Various C–H…π and C–H…Br interactions play an important role in stabilizing the molecular structure and then give rise to a 3D supramolecular structure of the ZnLBr₂ complex. After characterization, the Schiff base and its complexes were screened in vitro for their antibacterial and antifungal activities by disk diffusion technique. Also the ability of the complexes for DNA cleavage was studied by agarose gel electrophoresis method. Finally, thermal behavior of the complexes has been studied by thermo-gravimetry and then some activation kinetics parameters of decomposition steps were evaluated based on TG/DTG plots.     

A fourfold interpenetrating diamond‐like three‐dimensional zinc(II) coordination polymer: synthesis,crystal structure and physical properties

Excellent fluorescence properties are exhibited by d¹⁰ metal compounds. The novel three‐dimensional Zn^II coordination framework, poly[[{μ₂‐bis[4‐(2‐methyl‐1H‐imidazol‐1‐yl)phenyl] ether‐κ²N³:N^3′}(μ₂‐furan‐2,5‐dicarboxylato‐κ²O²:O⁵)zinc(II)] 1.76‐hydrate], {[Zn(C₆H₂O₅)(C₂₀H₁₈N₄O)]·1.76H₂O}_n, has been prepared and characterized using IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The crystal structure analysis revealed that the compound exhibits a novel fourfold interpenetrating diamond‐like network. This polymer also displays a strong fluorescence emission in the solid state at room temperature.     

Ag(I) coordination polymer with pyrazine sulfonic acid: synthesis,crystal structure,and fluorescence property

A one-dimensional rigid, linear Ag(I) coordination polymer with pyrazine sulfonic acid, [Ag₂L₂?·?H₂O] _n (L?=?pyrazine sulfonic acid) has been synthesized and characterized by elemental analyses, infrared spectroscopy, thermogravimetric analysis, and X-ray crystallography. The structure determination shows Ag(I) centers linked by bridging pyrazine ligands to give a double-chain structure sustained by weak Ag-O and Ag-N interactions. The sulfonate and pyrazine are all involved in hydrogen bonding interaction. The interactions combine with weak π-π stacking to play deciding roles defining the supramolecular structures. A powder X-ray diffraction study implies good phase purity. Solid-state fluorescence quenching and thermal stability are also discussed.     

Unusual co-ordination behaviour of imidazole-4-acetic acid. Synthesis, crystal structure and vibrational studies of one-dimensional co-ordination polymer of zinc(II) with two different ligand forms

This work is devoted to structural and vibrational studies of novel 1D polymeric zinc(II) complex [ZnCl(ia)(Hia)]·H₂O (infinity) [Hia=imidazole-4-acetic acid]. It has been found for the first time that the ia anion is acting as bidentate bridging ligand with N1 and carboxylate oxygen atoms as binding centres. The quasi-tetrahedral coordination polyhedron is completed by one chloride anion and monodentate Hia ligand bonded with zinc(II) cation via carboxylate oxygen atom. The compound crystallise in the triclinic P space group with Z=2. The polymer chains are held together by hydrogen bonding network involving the N---H and carboxylate groups, chloride ions and water molecules. The differences between normal vibrations of two ligand forms present in the complex are discussed on the basis of the density functional calculations (DFT) performed for natural and N-deuterated isotopomers. The assignment of the observed MIR and Raman bands is given in terms of potential energy distribution (PED).     

A twofold interpenetrating two‐dimensional zinc(II) coordination polymer: synthesis,crystal structure and physical properties

A novel twofold interpenetrating two‐dimensional (2D) Zn^II coordination framework, poly[[(μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene‐κ²N³:N³)(μ‐naphthalene‐2,6‐dicarboxylato‐κ²O²:O⁶)zinc(II)] dimethylformamide monosolvate], {[Zn(C₁₂H₆O₄)(C₁₄H₁₄N₄)]·C₃H₇NO}_n or {[Zn(1,3‐BMIB)(NDC)]·DMF}_n (I), where H₂NDC is naphthalene‐2,6‐dicarboxylic acid, 1,3‐BMIB is 1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene and DMF is dimethylformamide, was prepared and characterized through IR spectroscopy, elemental analysis, thermal analysis and single‐crystal X‐ray diffraction. Single‐crystal X‐ray diffraction analysis revealed that (I) exhibits an unusual twofold interpenetrating 2D network. In addition, it displays strong fluorescence emissions and a high photocatalytic activity for the degradation of Rhodamine B (RhB) under UV‐light irradiation.     

A threefold interpenetrating two‐dimensional zinc(II) coordination polymer: synthesis,crystal structure and selective luminescence sensing properties

The Fe³⁺ ion is the most important element in environmental systems and plays a fundamental role in biological processes. Iron deficiency can result in diseases and highly selective and sensitive detection of trace Fe³⁺ has become a hot topic. A novel two‐dimensional Zn^II coordination framework, poly[[μ‐4,4′‐bis(2‐methylimidazol‐1‐yl)diphenyl ether‐κ²N³:N^3′](μ‐4,4′‐sulfonyldibenzoato‐κ²O:O′)zinc(II)], [Zn(C₁₄H₈O₆S)(C₂₀H₁₈N₄O)]_n or [Zn(SDBA)(BMIOPE)]_n, (I), where H₂SDBA is 4,4′‐sulfonyldibenzoic acid and BMIOPE is 4,4′‐bis(2‐methylimidazol‐1‐yl)diphenyl ether, has been prepared and characterized by IR, elemental analysis, thermal analysis and X‐ray diffraction analysis, the latter showing that the coordination polymer exhibits a threefold interpenetrating two‐dimensional 4⁴‐ sql network. In addition, it displays a highly selective and sensitive sensing for Fe³⁺ ions in aqueous solution.     

Microwave-assisted synthesis,characterization, and antimicrobial activity of some odorant Schiff bases derived from naturally occurring carbonyl compounds and anthranilic acid

Nine odorant Schiff bases, namely 2-(4-methoxybenzylideneamino) benzoic acid, 2-(benzylideneamino) benzoic acid, 2-(3-phenylallylidene amino) benzoic acid, 2-(3,7-dimethyloct-2,6-enylideneamino) benzoic acid, 2-(3,7-dimethyloct-6-enylideneamino) benzoic acid, 2-(4-isopropylbenzylideneamino)benzoic acid, 2-(3,4-dimethoxybenzylideneamino) benzoic acid, 2-(1-phenylethylideneamino) benzoic acid, and 2-[(4-(2,6,6-trimethylcyclohex-2-enyl)-but-2-enylideneamino)benzoic acid, were prepared by condensation of anthranilic acid with corresponding naturally occurring carbonyl compounds (anisaldehyde, benzaldehyde, cinnamaldehyde, citral, citronellal, cuminaldehyde, veratraldehyde, acetophenone, and α-ionone) employing conventional and microwave irradiation methods. These compounds were characterized with the aid of elemental and spectral (FT-IR, ¹H NMR, and ¹³C NMR) analysis. Microwave irradiation method was efficient in terms of reduced reaction time, solvent use, and increased yields of these compounds without affecting their olfactory characteristics. These Schiff bases also exhibited olfactory characteristics for various fragrance compositions and varied antimicrobial activity against Aspergillus niger, Penicillium chrysogenum, Staphylococcus aureus, and Escherichia coli.     

Hydrothermal synthesis,crystal structure and photoluminescence of two homochiral zinc(II) coordination polymers

Metal–organic frameworks (MOFs) have potentially useful applications and an intriguing variety of architectures and topologies. Two homochiral coordination polymers have been synthesized by the hydrothermal method, namely poly[(μ‐N‐benzyl‐L‐phenylalaninato‐κ⁴O,O′:O,N)(μ‐formato‐κ²O:O′)zinc(II)], [Zn(C₁₆H₁₆NO₂)(HCOO)]_n, (1), and poly[(μ‐N‐benzyl‐L‐leucinato‐κ⁴O,O′:O,N)(μ‐formato‐κ²O:O′)zinc(II)], [Zn(C₁₃H₁₈NO₂)(HCOO)]_n, (2), and studied by single‐crystal X‐ray diffraction, elemental analyses, IR spectroscopy and fluorescence spectroscopy. Compounds (1) and (2) each have a two‐dimensional layer structure, with the benzyl or isobutyl groups of the ligands directed towards the interlayer interface. Photoluminescence investigations show that both (1) and (2) display a strong emission in the blue region.     

Calcium complex of 2,5-dihydroxybenzoic acid (gentisic acid): synthesis,crystal structure,and spectroscopic properties

The synthesis, crystal structure, and spectral characteristics (IR, Raman, and ¹H and ¹³C NMR) of a monomeric hexa(aqua)calcium compound, viz. [Ca(C₇H₅O₄)₂(H₂O)₆]·H₂O (C₇H₅O₄ = 2,5-dihydroxybenzoate), are reported. The central Ca(II) located on a twofold axis is eight coordinate in an approximate square antiprismatic environment, bonded to two monodentate 2,5-dihydroxybenzoate ligands via the carboxylate oxygen, and six waters. The adjacent monomeric units are linked with the aid of several O–H?O hydrogen bonds.     

Synthesis,crystal structure and fluorescence properties of two dinuclear zinc(II) complexes incorporating tridentate (NNO) Schiff bases

Reactions of hydrated zinc(II) trifluoroacetate and sodium azide with two tridentate Schiff bases HL¹ (2-((E)-(2-(dimethylamino)ethylimino)methyl)-4-chlorophenol) and HL² (2-((E)-(2-(dimethylamino)ethylimino)methyl)-4-bromophenol) under the same reaction conditions yielded two dinuclear isostructural zinc(II) complexes, [Zn(L¹)(N₃)]₂ (1) and [Zn(L²)(N₃)]₂ (2), respectively. The complexes were characterized systematically by elemental analysis, UV–Vis, FT-IR, and ¹H NMR spectroscopic methods. Single-crystal X-ray diffraction studies reveal that each of the dinuclear complexes consists of two crystallographically independent zinc(II) ions connected by double bridging phenoxides. All zinc(II) ions in 1 and 2 are surrounded by similar donor sets and display distorted square–pyramidal coordination geometries. The ligands and complexes reveal intraligand ¹(π → π*) flourescence. The enhancement of the fluorescence intensities for the complexes compared to the ligands indicates their potential to serve as photoactive materials.     

Synthesis,characterization and crystal structure of a novel three-dimensional supramolecular architecture formed by manganese(II) and pyridine-2,5-dicarboxylic acid

A novel three-dimensional supramolecular compound formed by Mn(II) and pyridine-2,5-dicarboxylic acid of formula [Mn(Pydc)₂(H₂O)₂] (Pydc?=?pyridine-2,5-dicarboxylic acid) has been synthesized and characterized by elemental analyses, IR, electronic spectra, thermogravimetric analysis and X-ray diffraction techniques. The X-ray structure shows that the central Mn(II) ion is coordinated by two water molecules and two chelated Pydc ligands. Water molecules coordinate with Mn(II) ions in the cis mode. Intermolecular hydrogen bonds play an important role in stabilization of the lattice and construction of the supramolecular network.     

Synthesis,characterization, crystal structure and biological activities of supramolecular compounds of Mn(II) and Zn(II) with dipicolinic acid and 8-hydroxyquinoline

Two compounds, (8-H₂Q)₂[Mn(dipic)₂] · 6H₂O (1) and (8-H₂Q)₂[Zn(dipic)₂] · 6H₂O (2) (8-HQ = 8-hydroxyquinoline (oxine), H₂dipic = dipicolinic acid), have been prepared and characterized by elemental, spectroscopic (IR and UV–Vis), and thermal analyses, magnetic measurements and single crystal X-ray diffraction techniques. Compounds 1 and 2 consist of two 8-hydroxyquinolinium cations, one bis(dipicolinato)M(II) anion (M = Mn(II) and Zn(II)) and six uncoordinated water molecules. Both 1 and 2 crystallize in the monoclinic space group C2/c. In the complex anion, each dipic ligand is tridentate through N of pyridine and oxygens of the carboxylate groups. Crystal packing of 1 and 2 is a composite of intermolecular hydrogen bonding interactions. The in vitro antibacterial and antifungal activities of 1 and 2 were evaluated by the agar well diffusion method by MIC (Minimal Inhibition Concentration), looking for compounds which display high-inhibitory effect against gram positive bacteria and fungi. No growth inhibition was observed against tested gram negative bacteria.     

A novel three‐dimensional zinc(II) coordination polymer based on 3,3′‐{[1,3‐phenylenebis(methylene)]bis(oxy)}dibenzoic acid and 1,4‐bis(pyridin‐4‐yl)benzene: synthesis,crystal structure and photocatalytic properties

A novel three‐dimensional (3D) Zn^II coordination polymer, namely, poly[[[1,4‐bis(pyridin‐4‐yl)benzene](μ₃‐3,3′‐{[1,3‐phenylenebis(methylene)]bis(oxy)}dibenzoato)zinc(II)] 1,4‐bis(pyridin‐4‐yl)benzene], {[Zn(C₂₂H₁₆O₆)(C₁₆H₁₂N₂)]·C₁₆H₁₂N₂}_n or {[Zn(PMBD)(DPB)]·DPB}_n, 1 , where H₂PMBD is 3,3′‐{[1,3‐phenylenebis(methylene)]bis(oxy)}dibenzoic acid and DPB is 1,4‐bis(pyridin‐4‐yl)benzene, has been synthesized by self‐assembly using zinc nitrate, a semi‐rigid dicarboxylic acid and a nitrogen‐containing ligand. The single‐crystal X‐ray structure determination indicates that 1 possesses an intriguing 3D architecture with a 4‐connected uninodal cds topology, which is constructed from dinuclear {Zn₂} clusters and V‐shaped PMBD^2? linkers. Compound 1 exhibits excellent photocatalytic activity on the degradation of the organic dyes Rhodamine B (RhB), Rhodamine 6G (Rh6G) and Methyl Red (MR).     

基于4-(2，4-二羧基苯氧基)邻苯二甲酸配体的锌配位聚合物的合成、结构及其荧光传感性能

基于H₄dpa和bpy (H₄dpa=4-(2,4-二羧基苯氧基)邻苯二甲酸,bpy=4,4''-联吡啶)为配体,在水热条件下设计、合成了金属锌配位聚合物(Zn-CP)[Zn(H₂dpa)(bpy)_1.5]_n (1),并用元素分析、红外光谱、X射线单晶衍射等对其进行了结构表征。在1中相邻Zn²⁺与H₂dpa^2-离子和bpy配位形成一维双链结构,相邻的一维双链通过氢键作用扩展形成三维超分子网结构。荧光研究表明：1是一种灵敏度高、选择性好、多响应的荧光传感器,可用于农药和硝基爆炸物的检测。有趣的是,2,4,6-三硝基苯(TNP)和嘧霉胺(Pth)对1的荧光发射显示出明显的猝灭效果,而抑霉唑(Ima)对1有荧光增强效果。此外,通过紫外可见吸收光谱、荧光寿命以及X射线光电子能谱探究了1的荧光传感机理。     

Construction of a PbII coordination polymer from a semi-rigid ditopic 2,2-biimidazole derivative: synthesis,crystal structure and characterization

<!?tlsb=-0.04pt>A new Pb^II coordination polymer, poly[0.75(aqua)[μ₃-4,4′-(1H,1′H-[2,2′-biimidazole]-1,1′-diyl)dibenzoato-κ⁵O,O′;N;O′′,O′′′]]lead(II)] 1.25-hydrate], {[Pb(C₂₀H₁₂N₄O₄)(H₂O)_0.75]·1.25H₂O}_n or {[Pb(L)(H₂O)_0.75]·1.25H₂O}_n ( 1 ) [H₂L = 4,4′-(1H,1′H-[2,2′-biimidazole]-1,1′-diyl)dibenzoic acid], was synthesized under solvothermal reaction conditions and characterized using microanalysis, IR spectroscopy and thermogravimetric analysis. Single-crystal structure analysis reveals that a two-dimensional corrugated layer structure is formed in 1 and that neighbouring layers are further extended into a three-dimensional structure by hydrogen-bonding interactions. In addition, a fluorescence sensing experiment towards Cu²⁺ based on the polymeric Pb^II complex was carried out.     

A new linear bismuth coordination polymer based on 1,10‐phenanthroline‐2,9‐dicarboxylic acid: ionothermal synthesis,crystal structure and fluorescence properties

A new linear bismuth(III) coordination polymer, catena‐poly[[chloridobismuth(III)]‐μ₃‐1,10‐phenanthroline‐2,9‐dicarboxylato‐κ⁶O²:O²,N¹,N¹⁰,O⁹:O⁹], [Bi(C₁₄H₆N₂O₄)Cl]_n, has been obtained by an ionothermal method and characterized by elemental analysis, energy‐dispersive X‐ray spectroscopy, IR spectroscopy, thermal stability studies and single‐crystal X‐ray diffraction. The structure is constructed by Bi(C₁₄H₆N₂O₄)Cl fragments in which each Bi^III centre is seven‐coordinated by one Cl atom, four O atoms and two N atoms. The coordination geometry of the Bi^III cation is distorted pentagonal–bipyramidal (BiO₄N₂Cl), with one bridging carboxylate O atom and one Cl atom located in the axial positions. The Bi(C₁₄H₆N₂O₄)Cl fragments are further extended into a one‐dimensional linear polymeric structure via subsequent but different centres of symmetry (bridging carboxylate O atoms). Neighbouring linear chains are assembled via weak C—H...O and C—H...Cl hydrogen bonds, forming a three‐dimensional supramolecular architecture. Intermolecular π–π stacking interactions are observed, with centroid‐to‐centroid distances of 3.678 (4) Å, which further stabilize the structure. In addition, the solid‐state fluorescence properties of the title coordination polymer were investigated.