Synthesis,Crystal Structure,Photophysical and Redox Properties of a Novel Ru(Ⅱ) Complex with Carbazole-grafted 2-(2-Pyridyl)benzimidazole

A novel Ru（Ⅱ） complex [（bpy）2Ru（PBC）]（PF6）2 （PBC = N-[4-（9-carbazole）butyl]-2-（2-pyridyl）benzimidazole） has been synthesized and verified by 1↑H NMR, elemental analysis and X-ray crystallography. The crystal （C48H40F12N8P2Ru, Mr = 1119.89） belongs to the triclinic system, space group P1, with a = 13.128（4）, b = 13.814（4）, c = 14.184（4） A, α = 84.112（6）, β = 88.473（6）, γ = 78.196（6）°, Z = 2, V = 2504.6（13）A^3, Dc = 1.485 g/cm^3, F（000） = 1132, R = 0.0750 and wR = 0.1896. The Ru atom adopts a distorted-octahedral coordination geometry with the bond distances and bond angles falling in normal ranges. The complex shows an intense metal-to-ligand charge transfer （1MLCT） （dπ（Ru） →π＊（L）） transition （ε ~1.2×10^4 dm^3mol^-1cm^-1） at 457 nm in the UV-Vis absorption spectrum and a strong red phosphorescence at 632 nm in the CH3CN solution at ambient temperature. An efficient intramolecular energy transfer process from the carbazole unit to the [（bpy）2Ru（PB）]^2＋ emissive center exists by selective optical-simulation. Its electrochemical behavior shows multiplicate redox processes based on the metal center, the grafting carbazole moiety and the 2-（2-pyridyl）benzimidazole unit.

Hydrothermal Synthesis,Crystal Structure and Fluorescence Spectrum Studies of a Novel Supramolecular Compound {[2-(2-Pyridyl)benzimidazoleH_2]_2·[BiCl_6]·Cl}

A novel supramolecular compound,{[2-（2-pyridyl）benzimidazoleH2]2·[BiCl6]·Cl},was synthesized by the hydrothermal reaction of o-phenylenediamine and α-pyridinecarboxylic acid with BiCl3 in 6.0 mol·L-1 HCl solution,and characterized by elemental analysis,IR,X-ray single-crystal diffraction and photoluminescence spectroscopy.The crystal （C24H22N6Cl7Bi,Mr= 851.61） belongs to the triclinic system,space group P1 with a =7.2887（18）,b =9.548（2）,c= 12.469（3）,α=85.306（4）,β=82.814（4）,γ=71.349（4）°,Z=1,V=814.9（3）3,Dc=1.735 g/cm3,μ（MoKα）=6.007 mm-1,F（000）=410,R=0.0307 and wR=0.0787.The bismuth ion and six chlorine ions construct a distorted octahedral configuration.The three-dimensional supramolecular network is built from electrostatic attractions,hydrogen bonds and π-π interaction between the BiCl6 anion,Cl anion and [2-（2-pyridyl）benzimidazoleH2] cation.The photoluminescence spectroscopy study shows that the title compound has a blue fluorescent emission at 450 nm in the solid state.

Hydrothermal Synthesis,Crystal Structure and Fluorescence Spectrum Studies of a Supramolecular Compound {[2-(2-Pyridyl)benzimidazoleH_2]^(2+)·[SbCl_5]^(2-)}_2

A new supramolecular compound, { [2-（2-pyridyl）benzimidazoleH2]2＋.[SBC15]2-}2, was synthesized by the hydrothermal reaction of o-diaminobenzene, 2-pyridinecarboxylie acid and SbCl3 in 1：1 HC1 solution, and characterized by chemical analysis, elemental analysis, IR spectra, thermogravimetfic analysis and fluorescence spectra. The crystal structure was deter- mined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P211c, with a = 16.0397（13）, b = 14.3189（12）, c = 15.6370（13） A, β = 105.8980（10）°, V = 3454.0（5） A3, Z = 4, C24H22Cl10N6Sb2, Mr = 992.48, Dc = 1.909 g/cm3,/z = 2.366 mm-1, S = 1.010, F（000） = 1920, R = 0.0254 and wR = 0.0555. The coordination anion, [SbCl5]2- which is a distorted tetragonal pyramid, is composed by coordinating action with Sb3＋ ion and five adjacent chloride ions. Every four coordination anions of [SbCl5]2- form a biquaternion ring structure through the secondary bonding of Sb...Cl. Moreover, the compound adopts a three-dimensional network supramolecular structure because of the hydrogen bonds and π-π stacking between the rings and the 2-（2-pyridyl）benzimidazole divalent cations. The title compound also shows good fluorescent behaviors.

Syntheses and Crystal Structures of Two New Supramolecular Architectures Constructed from the Main Group Metal Chloride and Protonated 2-(3-Pyridyl)benzimidazole

The reactions of SbCl3 and HgCl2 with 2-（3-pyridyl）benzimidazole （PyBIm） in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-（3-pyridinio）benzimidazolium （H2PyBIm） cations and the corresponding metal ions are bonded with chloride atoms into coordination anions, forming two new coordination compounds, namely, （H2PyBIm）（SbCl5） 1 and （H2PyBIm）2（Hg2Cl8） 2. Both compounds were characterized by X-ray crystallography. Crystal data for 1： triclinic, space group P1^- with a = 5.7030（7）, b = 9.0625（11）, c = 16.5929（18） A, α = 91.808（7）°, β = 93.234（6）, γ = 99.216（7）°, C12H11N3SbCl5, Mr = 496.24, V = 844.44（17） A^3, Z = 2, Dc = 1.952 g/cm^3, μ（MoKα） = 2.419 mm^-1, F（000） = 480, the final R = 0.0496 and wR = 0.1382 for 3433 observed reflections （I 〉 2σ（I））. Crystal data for 2： monoclinic, space group P21/c with a = 7.8061（5）, b = 15.8127（9）, c = 12.2435（9） , β = 91.955（4）o, C24H22N6Hg2Cl8, Mr = 1079.26, V = 1510.40（17） 3, Z = 2, Dc = 2.373 g/cm3, μ（MoKα） = 10.889 mm-1, F（000） = 1008, the final R = 0.0293 and wR = 0.0562 for 2854 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that the antimony（III） is five-coordinated, exhibiting a slightly distorted square-pyramidal coordination geometry; while in 2, a dimeric [Hg2Cl8]^4-anion consists of two trigonal bipyramids sharing two common edges. The organic cations and coordination anions are connected into a one-dimensional belt and a two-dimensional sheet through N-H···Cl hydrogen bonding interactions in compounds 1 and 2, respectively; both are further aggregated into 3D frameworks by strong π-π contacts.

Some New Derivatives of 3H-benzo[b]Furo[3,2-f]- Benzimidazole with Expected Biological Activity

On the base of benzimidazole and benzofuran containing heterocyclic system, several derivatives with expected biological activity were synthesized. 2,3-diaminodibenzofuran was the primary substance. Adding various cyclic agents, 2-phenil was got, 2-（o-chlorophenil）, 2-（o-oxyphenil）, 2-chlorometyl- and 2-hydroximethyl-3H-benzo[b[furo（3,2-f] benzimidazoles. The aforementioned substances were characterized by IR and NMR spectroscopy.

Synthesis, Electrochemistry and Antitumor Activity of 1’H, 3’H(Me)-spiro-[(aza)benzimidazoline-2’, 3-(1,2-diferrocenylcyclopropenes)], 2-(1,2-Diferrocenylvinyl)benz- and Azabenzimidazoles

A new method of synthesis of 2-(1,2-diferrocenylvinyl)benz- and azabenzimidazoles (3a-f), (4a-f) and 1’H,3’H(Me)-spiro-[(aza)benzimidazoline-2’,3-(1,2-diferrocenylcyclopropenes)] (5a-f) via reactions of diferrocenyl(methylsulfanyl)cyclopropenylium iodide (1) with aromatic o-diamines (2a-f) in the presence of Et3N (80°C - 82°C) is described. The structures of the resultant compounds are established using IR, 1H and 13C NMR spectroscopy, mass spectrometry and elemental analysis. The structure of one compound, cis-2-(1,2-diferrocenylvinyl)-1-methylbenzimidazole (3b), is confirmed by X-ray diffraction analysis. The electrochemical properties of compounds 3a, 3b, 3d and 5f are investigated using cyclic square wave voltammetry. Two electrochemical processes (I-II), attributed to oxidation of the ferrocene moieties, and the values of E0’(I), E0’(II), DE0’(II-I) and comporportionation constant Kcom are reported. The bioactivities of seven compounds 3a, 3c-f, 5d, 5f are evaluated. Compound 5f is the most active compound with a modest cytotoxic activity against six human cancer cell lines: U-251 (glioma), PC-3 (prostate cancer), K-562 (leukemia), HCT-15 (colon cancer), MCF-7 (breast cancer) and SKLU-1 (lung cancer).

Synthesis, Crystal Structure, Fluorescent Property and DFT Calculations of a New Zn(Ⅱ) Complex Based on 3-(2-Pyridyl)-5-(4-pyridyl)-1H-1,2,4-triazole

A new coordination compound Zn（2,4＇-bpt）2（H2O）（1） based on the versatile ligand 2,4＇-Hbpt（2,4？-Hbpt = 3-（2-pyridyl）-5-（4-pyridyl）-1H-1,2,4-triazole） was prepared by hydrothermal reactions. The structure of complex 1 has been characterized by X-ray single-crystal diffraction, elemental analysis, X-ray powder diffraction, IR spectrum analysis and thermogravimetric analysis. Single-crystal X-ray diffraction analysis indicates that the complex belongs to monoclinic system, space group C2/c with a = 23.877（3）, b = 0.7483（9）, c = 1.2492（2） A, b = 92.681（2）°, V = 2230.6（4） A^3, Z = 4, Dc = 1.572 g/cm^3, m = 1.143 mm^-1, Mr = 527.85 and F（000） = 1080. The final R = 0.0581 and wR = 0.0898 with I 〉 2s（I）. 1 is a 0D motif which is connected by hydrogen bonds to form a corrugated 1D pattern. In addition, 1 shows strong photoluminescent emissions in the solid state at room temperature which can be used as potential optical materials. Theoretical calculations based on density functional theory（DFT） were employed in order to explicate the stability and chemical reactivity of 2,4＇-Hbpt with different conformations. The results indicated that conformation I is more stable and prior to coordination in the reactions.

Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands

Six new transition metal complexes, [Zn（HBTC）（PYTPY）]n·n PYTPY（1）, [Cu（HBTC）（PYTPY）]n·n PYTPY（2）, [Co（HBTC）（PYTPY）]n·n DMF（3）, [Mn（HBTC）（PYTPY）]n·n DMF（4）, [Cd（HBTC）（PYTPY）（H2O）]n·2nH2O（5）, and [Co（HBTC）（PYTPY）（H2O）2]（6）,（H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4＇-（4-pyridyl）-2,2＇：6＇,2＇＇-terpyridine, DMF = N,N？-dimethylformamide）, have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional（3D） supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties.

Syntheses, Structures and Photoluminescence of the Cadmium(Ⅱ) and Copper(Ⅱ) Complexes Based on 4'-(4''-Pyridyl)-2,2':6',2''-terpyridine and 1,4-Benzenedicarboxylic Acid Ligands

Two new metal-organic complexes [Cd2（1,4-BDC）（4-pytyp）（H2O）4]·（1,4-BDC）（1） and [Cu2（1,4-BDC）（4-pytyp）2（H2O）2]·（1,4-BDC）·8H2O（2）（4-pytyp = 4＇-（4＇＇-pyridyl）-2,2＇：6＇,2＇＇-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid） have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail.

A Two-dimensional Metallic Oxide Constructed from Molybdenum Clusters and Ag(Ⅰ)-[3-(2-pyridyl)-pyrazole] Cationic Coordination Components

A new polyoxomolybdate compound [Ag 3 （HL） 4 ]（PMo 12 O 40）] 1 （HL=3-（2-pyridyl）pyrazole） has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectroscopy.The compound crystallizes in triclinic,space group P1 with a=10.375（3）,b=12.076（3）,c=13.196（4）,α=84.170（4）,β=71.961（3）,γ=86.326（4）°,V=1563.1（7）3,C 32 H 28 Ag 3 Mo 12 N 12 O 40 P,M r=2726.52,D c=2.897 g/cm 3,μ（MoKα）=3.366 mm 1,F（000）=1284,Z=1,the final R=0.0587 and wR=0.1312 for 4139 observed reflections （I 2σ（Ⅰ））.X-ray diffraction analyses reveal that the PMo 12 O 40 3clusters in compound 1 are linked by four Ag 3 （HL） 4 3＋ units via the terminal oxygen atoms to form a two-dimensional architecture.The symmetrical unit of Ag 3 （HL） 4 3＋ exhibits two distinct Ag（Ⅰ） environments：a two-coordinate {AgN 2 } site and a five-coordinate {AgN 3 O 2 } site which links to two molybdate clusters.

Catalytic Kinetic on the Thermal Decomposition of Ammonium Perchlorate with a New Energetic Complex Based on 3,5-Bis(3-pyridyl)-1H-1,2,4-triazole

A new energetic complex,[Co（3,3？-Hbpt）（Htm）]·H_2O（1,3,3？-Hbpt = 3,5-bis（3-pyridyl）-1H-1,2,4-triazole and H_3tm = trimesic acid）,has been synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction,elementary analysis,IR spectroscopy,thermogravimetric analysis and X-ray powder diffraction. Single-crystal X-ray diffraction indicates that the complex belongs to triclinic system,space group P 1 with a = 10.0911（1）,b = 10.2573（1）,c = 10.6393（1） ？,α = 103.793（2）,β = 101.041（2）,γ = 107.918（3）o,V = 974.9（2） ？~3,Z = 2,D_c = 1.732 g·cm-3,μ = 0.941 mm^（-1）,M_r = 508.31,F（000） = 518,the final R = 0.0523 and wR = 0.0935 with I 〉 2σ（I）. In the title complex,Co（Ⅱ） ions are connected by Htm2-anions generating 1D ladder-like chains which are linked by 3,3？-Hbpt to form 1D cages. In addition,the thermal decomposition of ammonium perchlorate（AP） with complex 1 was explored by differential scanning calorimetry（DSC）. AP is completely decomposed in a shorter time in the presence of complex 1,and the decomposition heat of the mixture is 2.531 kJ·g^（-1）,significantly higher than that of pure AP. By Kissinger＇s method,the ratio of Ea/ln（A） is 11.05 for the mixture,which indicates that complex 1 shows good catalytic activity toward the AP decomposition.

Synthesis and Crystal Structure of a Polyoxomolybdate Framework Modified by Mn-L Units(L=3-(2-Pyridyl)pyrazole)

A new polyoxomolybdate compound,namely {[MnII（L）（4,4？-Hbipy）（H2O）2]2 [Mo5O15（PO4）2]}.2H2O 1（L = 3-（2-pyridyl）pyrazole,4,4＇-Hbipy = protonated 4,4＇-bipyridine）,was designed and synthesized under hydrothermal conditions.Single-crystal X-ray diffraction analysis result reveals that the [Mo5O15（PO4）2]6-cluster in compound 1 links to two MnII cations via the oxygen of PO43-,which is further coordinated by one 3-（2-pyridyl）pyrazole,one 4,4＇-Hbipyridine,and two water molecules.

A Two-dimensional Metallic Oxide Constructed from Molybdenum Clusters and Zn(Ⅱ)-[3-(2-pyridyl)pyrazole] Cationic Coordination Components

A new polyoxomolybdate compound [Zn（HL）2（Mo8O26）（4,4＇-Bipy）]·（4,4＇-Bipy） （HL = 3-（2-pyridyl）pyrazole, 4,4＇-Bipy = 4,4＇-bipyridine） 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses, TG and IR spectroscopy. The compound crystallizes in monoclinic, space group C2/c with a = 18.060（4）, b = 13.870（3）, c = 19.360（4） A, β = 93.50（3）°, V = 4840.5（17） 3, C36H30Mo8N10O26Zn, Mr = 1851.59, Dc = 2.541 g/cm^3, μ（MoKα） = 2.589 mm·1, F（000） = 3560, Z = 4, the final R = 0.0328 and wR = 0.0870 for 4005 observed reflections （I 〉 2σ（I））. X-ray diffraction analyses reveal that compound 1 is constructed from Mo8O264-units linked by Zn（HL）22＋ and 4,4＇-Bipy. Mo8O264-is connected by Zn（HL）2^2＋ via terminal oxygen atoms along the [010] axis forming chains, which are further linked by 4,4＇-Bipy along the [001] axis forming a two-dimensional network structure.

One-dimensional Zigzag Chain Composed of HgI_2 Unit and 2,5-Bis(4-pyridyl)-1,3,4-thiadiazole:[HgI_2(C_(12)H_8N_4S)]

The title compound, [HgI2（C12H8N4S）], has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 14.086（2）, b = 6.0365（6）, c = 20.286（2）°A,β= 108.818（5）°, V = 1632.7（3）°A^3, Mr = 694.67, Z = 4, D, = 2.826 g/cm^3,μ= 13.331 mm^-1, F（000） = 1240, S = 1.108, the final R = 0.0438 and wR = 0.0934 for 3085 observed reflections （I〉 2σ（I））. The Hg（Ⅱ） atom is coordinated by two 2,5-bis（4-pyridyl）-1,3,4-thiadiazole （L） molecules and two iodine anions in a distorted tetrahedral coordination geometry. Mercury atoms are linked by the organic ligands to form a one-dimensional zigzag chain. It is noteworthy that such 1D zigzag chains are extended into a two-dimensional double layer framework through I…I interactions

A One-dimensional Metallic Oxide Constructed from Molybdenum Clusters and Mn(Ⅱ)-[3-(2-pyridyl) pyrazole] Cationic Coordination Components

A new polyoxomolybdate compound [Mn II （L） 2 （Mo 8 O 26） 0.5 ] 2n （1,L=3-（2-pyridyl）pyrazole） has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectroscopy.The compound crystallizes in the triclinic system,space group P1 with a=10.063（4）,b=11.554（5）,c=11.554（5）,α=88.89,β=74.839（4）,γ=74.839（4）o,V=1249.8（9） 3,C 16 H 14 MnMo 4 N 6 O 13,M r=937.03,D c=2.490 g/cm 3,μ（MoKα）=2.521 mm 1,F（000）=898,Z=2,the final R=0.0390 and wR=0.0970 for 4000 observed reflections （I 2σ（Ⅰ））.Single-crystal X-ray diffraction analysis results reveal that compound 1 owns a chain structure based on β-[Mo 8 O 26 ] 4anions,which are linked by Mn II （L） 2 units via the terminal oxygen atoms.

Synthesis and Crystal Structure of (2S,5S)-1-Aza-2- (2-pyridyl)-3-oxa-4,4-diphenylbicyclo [3.3.0] Octane

The title compound (C23H22N2O) 3 has been synthesized by the reaction of (S)- (-)-1,1-diphenyl-2-pyrrolidinemethanol 1 with 2-pyridinecarboxaldehyde 2 in refluxing benzene catalyzed by TsOH, and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space group P212121 with a = 8.4747(8), b = 10.8829(10), c = 19.777(2) , Mr = 342.43, V =1824.0(3) 3, Dc = 1.247 g/cm3, Z = 4, m = 0.077 mm-1 and F(000) = 728. The structure was solved by direct methods and refined by full-matrix least-squares techniques to the final R = 0.0497 and wR = 0.0927.

Comparative Studies of 1,4-Bis[2-(4-Pyridyl)ethenyl]-benzene Using Density Functional Theory

The optimized molecular structure and harmonic vibrational frequencies of a 1,4-bis [ 2-（4-pyridyl）ethenyl]- benzene（BPENB） molecule were calculated via five popular density functional theory（DFI＇） methods. On the basis of the comparison between calculated and experimental results, it is concluded that the B3PW91 and B3LYP methods are superior to the others in optimizing structures, and the BPW91 method reproduces the observed fundamental fre-quencies most satisfactorily.

A Highly Sensitive and Selective Spectrofluorimetric Method for the Determination of Arsenic at Pico-Trace Levels in Some Groundwater, Real, Environmental, Biological, Food and Soil Samples Using 2-(<i>α</i>-Pyridyl)-Thioquinaldinamide

A very simple, ultra-sensitive, highly selective and non-extractive new spectrofluorimetric method for the determination of arsenic at pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been developed. PTQA has been proposed as a new analytical reagent for the direct non-extractive spectrofluorimetric determination of Arsenic (V). This novel fluorimetric reagent, PTQA becomes oxidized in a slightly acidic (0.025 - 0.1 M H2SO4) solution with Arsenic (V) in absolute ethanol to produce highly fluorescent oxidized product (λex = 303 nm;λem = 365 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.025 - 0.1 M H2SO4) for the period between 2 min and 24 h. Linear calibration graphs were obtained for 0.001 - 800-μgL-1 of As, having a detection limit of 0.1-ngL-1;the quantification limit of the reaction system was found to be 1-ngL-1 and the RSD was 0% - 2%. A large excess of over 60 cations, anions and complexion agents (like, chloride, phosphate, azide, tartrate, oxalate, SCN, etc.) do not interfere in the determination. The developed method was successfully used in the determination of arsenic in several Certified Reference Materials (alloys, steels, ores, human urine, hair, nails, bovine liver and sediments) as well as in some biological fluids (human blood, urine, hair, nail and milk), soil samples, food samples (vegetables, fruits, rice, corn and wheat), solutions containing both arsenic (III) and arsenic (V) speciation and complex synthetic mixtures. The results of the proposed method for assessing biological, food and soil samples were comparable with both ICP-OES & AHG-AAS and were found to be in excellent agreement.

A Highly Sensitive and Selective Spectrofluorimetric Method for the Determination of Vanadium at Pico-Trace Levels in Some Real, Environmental, Biological, Soil and Food Samples Using 2-(<i>α</i>-Pyridyl)-Thioquinaldinamide

A new spectrofluorimetric reagent 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been synthesized and characterized through novel reaction techniques. A very simple, ultra-sensitive and highly selective non-extractive new spectrofluorimetric method for the determination of vanadium at Pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been developed. PTQA has been proposed as a new analytical reagent for the direct non-extractive spectrofluorimetric determination of vanadium (V). This novel fluorimetric reagent, PTQA becomes oxidized in a slightly acidic (0.0035 - 0.0085 M H2SO4) solution within vanadium (V) in 20% ethanol to produce highly fluorescent oxidized product (λex = 319 nm;λem = 371 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.0035 - 0.0085 M H2SO4) for the period between 5 min and 24 h. Linear calibration graphs were obtained for 0.001 - 600-μg·L-1 of V, having a detection limit of 0.3-ng·L-1;the quantification limit of the reaction system was found to be 3-ng·L-1 and the RSD was 0% - 2%. A large excess of over 60 cations, anions and complexing agents (like, chloride, phosphate, azide, tartrate, oxalate, SCN- etc.) do not interfere in the determination. The developed method was successfully used in the determination of vanadium in several Certified Reference Materials (alloys, steels, serum, bovine liver, drinking water, soil and sediments) as well as in some environmental waters (potable and polluted), biological fluids (human blood, urine, hair and milk), soil samples and food samples (vegetables, rice and wheat) solutions containing both vanadium (IV) and vanadium (V) speciation and complex synthetic mixtures. The results of the proposed method for assessing biological, food and vegetable samples were comparable with inductively coupled plasma optical emission spectroscopy (ICP-OES) and atomic-absorption spectrophotometer (AAS) was found to be in excellent agreement.

Synthesis,Structure,and Magnetic Property of One Snake-shaped Copper(Ⅱ)-organic Compound:Cu[Cu_2(PP)_2](CBPC)_2]·2(H_2O)

One novel copper（II）-organic compound,namely Cu[Cu2（PP）2]（CBPC）2]·2（H2O）（1,H2CBPC = 1-[（2＇-carboxybiphenyl-4-yl）methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-（2-pyridyl）pyrazole）,was designed and synthesized under hydrothermal conditions.X-ray diffraction analysis reveals that two Cu（II）ions in the quasi-planar dimmer of [Cu2（PP）2] are linked by the carboxylate oxygen atoms on the phenyl ring and the imidazole ring,respectively,yielding one snake-shaped structure.Magnetic measurements reveal that compound 1 shows the strongly antiferromagnetic property.Crystal data of 1：C58H52Cu3N10O10,Mr = 1239.72,monoclinic,P21/c,a = 14.900（7）,b = 15.029（7）,c = 12.308（6）,β = 102.519（9）o,V = 2691（2）3,Z = 2,Dc = 1.530 g/cm3,F（000）= 1274,μ = 1.246 mm-1,R = 0.0416,wR = 0.0780（I 2σ（I））and S = 0.999.