Synthesis and Crystal Structure of a New Mononuclear Cobalt(Ⅲ) Complex with 2,2′-Dipyridylamine and Glycine as Ligands

A new mononuclear cobalt(III) complex [Co(dpa)2(Gly)](ClO4)2′4H2O was synthesized by the reaction of Co2+, glycine (gly) and 2,2′-dipyridylamine (dpa) in a methanol-water solution, and its structure was characterized by IR, EA, ES-MS and X-ray structure analysis. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.8795(2), b = 13.2904(2), c = 19.1104(2) , β = 109.378(1)°, V = 3085.89(8) 3, Z = 4, Mr = 746.36, Dc = 1.606 g/cm3, μ = 0.808 mm-1, F(000) = 1536, the final R = 0.0543 and wR = 0.1306 for 5393 independent reflections. The magnetic measurement of the compound at room temperature shows that it is diamagnetic and the cobalt ion is in low spin +3 oxidation state. ES-MS experiments show that the [Co(dpa)2(Gly)]2+ cation is very stable in the methanol solution.     

SYNTHESIS AND MOLECULAR STRUCTURE OF NOVEL BINUCLEAR COBALT COMPLEX WITH MIXED VALENCE STATE Co(Ⅰ)Co(Ⅱ) (μ-Ph_2Ppy)_2(μ-CO)_2Cl_3

A novel binuclear cobalt complex with mixed valence state Co(Ⅰ)Co(Ⅱ)(μ-Ph_2Ppy)_2(μ-CO)_2Cl_3 has been prepared, Ph_2Ppy=2-(diphenyl phosphino)pyridine, and its molecular structure determined by using 3569 independent reflections. The complex was crystallized in the orthorhomblc space group P2_1nb with a=13.32(1), b=14.31(1),c=18.94(2) and Z=4. The structure was solved by direct method and full-matrix least squares refinement carried out. The final R value is 0.072.If the Co-Co bond is not taken into account, two cobalt atoms exhibit a five-coordlnate reformed trigonal bipyramid configuration (formal oxidation state +1) and a six-coordinate reformed octahedral configuration (formal oxidation state +2), respectively. The Co-Co distance is 2.685(1). The molecule belongs to the C_(2v), point group. A new W-frame compound with mixed valence state Co(0)Co(Ⅰ)(μ-Ph_2Ppy)_2(μ-CO)(CO)Cl can be formed by reducing this complex.     

Synthesis, Crystal Structure and Fluorescene of a One-dimensional Compound {CdI2（2,2＇-bipy）}n

The title compound, {CdI2(2,2'-bipy)}n, was prepared by the hydrothermal reaction of CdI2 and 2,2'-bipy in an aqueous solution, and its crystal structure was determined by X-ray single-crystal analysis. Crystallographic data for 1: C10H8N2CdI2, monoclinic system, space group C2/c, a = 16.927(1), b = 10.0925(7), c = 7.7422(3) (A), β = 106.0629(4)°, V = 1271.00(14)(A)3, Z = 4, F(000) = 944, μ = 6.546 mm-1, Dc= 2.730 g/cm3, Mr = 522.38, the final R = 0.0309 and wR = 0.0805 for 1310 observed reflections (I＞2σ(Ⅰ)). X-ray crystal structure analysis shows that the Cd atom is coordinated by four iodines and two N atoms from one 2,2'-bipy to form an 1-D chain-like structure through bridging iodines. The fluorescene of the title compound was also discussed.     

Synthesis,Structure and Oxidation Reaction of Tetrakis-pyridino-cobalt(Ⅱ) Dichromate

The title compound was prepared from the mixture of cobalt ( Ⅱ ) acetate, chromium trioxide and pyridine in an aqueous solution, and its structure was determined by X-ray single crystal diffraction method. A number of alcohols, benzyl halides and benzy-lamines can be oxidized by this oxidant to the corresponding aldehydes in high yields.     

Synthesis, Crystal Structure and DNA Binding Studies of α,α'-Bis(3,5-bismethyl-1-pyrozolyl)- carbene-acetyl-isopropenyl Hydrazine

The title compound α,α'-bis(3,5-bismethyl-pyrozole-N-yl)-carbene-acetyl-isopro-penyl hydrazine (C16H22N6O, Mr = 314.40) has been prepared. It was characterized by elemental analysis as well as IR, MS, 1H-NMR and 13C-NMR spectra. Its crystal structure was determined by single-crystal X-ray diffraction, getting the following data: triclinic, space group P1 with a = 6.9734(16), b = 10.773(3), c = 12.001(3) A, α = 75.311(4), β = 82.695(4), γ = 77.143(4)°, Z = 2, V = 847.9(3) A3, Dc : 1.231 g/cm3, F(000) = 336 and μ(MoKα) = 0.082 mm-1 (λ = 0.71073 A). The results of crystal structure determination show that there exist intermolecular and intramolecular hydrogen bonds, resulting in a two-dimensional supramolecular framework of the title compound. The binding of the title compound to DNA was investigated by absorption, emission, and viscosity measurements. The title compound shows absorption hyperchromicity accompanied by a blue shift at about 254 nm. The binding constant Kb for the title compound has been determined to be 1.89 × 104 M-1 from absorption measurements. The addition of the title compound to DNA pretreated with EB causes appreciable reduction in the emission intensity, indicating that the DNA-bound EB fluorophore is partially replaced by the title compound. The value of K is 3.093 × 104 M-1. The relative viscosity of DNA decreased with the addition of the title compound. Results suggest that the title compound binds to DNA with a non-classical intercalative or groove interaction mode. The observed efficient nuclease activity of the title compound is interesting and may have further influences on the chemistry of DNA minor groove binders.     

Synthesis and Structural Characterization of Co( Ⅱ ) Coordination Polymer [Co(μ-phth)(imi)2]n

A new cobalt( Ⅱ ) complex [Co(μ-phth)(imi)2]n (phth = o-phthalato, imi = imidazole)has been synthesized by the reaction of CoCl2 with disodium o-phthalate and imidazole. The crystal structure of the compound has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic system, space group Pn with a = 8.405(1), b = 9.995(1), c = 9.996(2) (A),β= 104.479(2),V= 813.0(2) (A)3, Dc= 1.467 g/cm3, C14H12N4O4Co, Mr= 359.21, F(000) = 366,μ = 1.079 mm-1, Z = 2, R = 0.0483 and wR = 0.1209 for 1583 observed reflections (Ⅰ＞ 2σ(Ⅰ)). In the title complex, the Co(Ⅱ) ions are bridged by o-phthalate ligands in a bidentate mode, producing a zigzag infinite chain structure. Each four-coordinated cobalt( Ⅱ ) center was coordinated by two oxygen atoms and two nitrogen atoms to give a distorted tetrahedral geometry. The chains are linked by hydrogen bonds between oxygen atoms belonging to carboxylate groups and hydrogen atoms of imidazole molecules, forming an unusual two-dimensional coordination polymer.     

Synthesis and Structure of an Interlock Network Frame of Cobalt(Ⅱ) Coordination Polymer {[Co(azpy)_2(NCS)_2]·1/4EtOH·1/2H_2O}_n (azpy=4,4′-Azobispyridine)

A compound {[Co(azpy)_2(NCS)_2]·1/4EtOH·1/2H_2O}_n(1), where azpy=4,4'-azobispyridine, was synthesized and characterized by means of IR, TGA-DTA, magnetic susceptibility and X-ray single crystal diffraction. It consists of two independent sets of fully interlocked two-dimensional networks with the dihedral angle 61.7°, organized in parallel stacks of the sheets which are made of edge-shared [Co(Ⅱ)]_4 squares separated by 0. 9062nm, and defined size rhombic channels. The thermal gravimetric analysis indicates that the framework is stable up to 198℃. The variable-temperature magnetic susceptibility measurements indicated that there is a weak antiferromagnetic interaction between the cobalt(Ⅰ) ions in the complex (1).     

Synthesis,Crystal Structure and Band Structure of Tb3Co4Sn（13）

A new intermetallic compound,Tb3Co4Sn13,has been synthesized by solid-state reaction of the corresponding pure elements in a welded tantalum tube at high temperature.Its crystal structure was established by single-crystal X-ray diffraction.Tb3Co4Sn13 crystallizes in cubic,space group Pm3n(No.223) with a = 9.5072(2) ,V = 859.33(3) 3,Z = 2,Mr = 2255.45,Dc = 8.717 g/cm3,μ = 34.369 mm-1,F(000) = 1906,and the final R = 0.0140 and wR = 0.0312 for 199 observed reflections with I > 2σ(I).The structure of Tb3Co4Sn13 belongs to the Yb3Rh4Sn13 type.It is isostructural with RE3Co4Sn13(RE = La,Ce),featuring a 3D [Co4Sn12] framework based on [CoSn6] trigonal prisms.The [CoSn6] trigonal prisms are interconnected via corner-sharing and Sn-Sn bonds to form a 3D [Co4Sn12] framework.The other Sn and Tb atoms are located in the spacers of the 3D framework.Band structure calculations indicate that Tb3Co4Sn13 is metallic.     

Synthesis and Crystal Structure of a Heptanuclear Trigonal Prismatic Cluster {PrCu_6} with Glycine and Imidazole as Ligands

A new heptanuclear trigonal prismatic cluster [PrCu6(μ3-OH)3(Gly)6im6](ClO4)6 was synthesized through the self-assembly of Pr^3 , Cu^2 , glycine and imidazole in aqueous solution and characterized by X-ray structure analysis. The compound belongs to the trigonal R3 space groupwith a=b=15.8761(2), c=23.4943(5) A, V=5128.4(1)A^3, Z=3, Dc=1.965 g/cm^3,μ=2.869mm^-1 F(000)=3012, the final R=0.0332 and wR=0.0844 for 3596 independent reflections. In the cation, the Pr3 ion is situated at the center of a prism formed by six copper atoms and coordinates to nine oxygen atoms with a tricapped trigonal prismatic coordination polyhedron. Six glycine ligands and six imidazole terminal ligands participate in constructing the cluster.     

Synthesis,Structure and Spectral Properties of a Novel Triaryl Substituted Triazole and Its Co(Ⅱ) Complex

The new compound 3-(2-pyridyl)-4-(p-methoxyphenyl)-5-(2-thienyl)-1,2,4-triazole L was synthesized and characterized by elemental analysis,IR,1H NMR,13C NMR,MS,UV and photoluminescent spectra.The complex CoL2(NCS)2 was prepared by the reaction of ligand L with Co(SCN)2,and its structure was characterized by single-crystal X-ray diffraction,IR,UV,elemental analysis and MS.The complex crystallizes in monoclinic,space group P21/n with a=13.7639(19),b=7.6641(11),c=18.409(3),β=101.549(3)o,V = 1902.6(5) 3,Z=2,C38H28CoN10O2S4,Mr=843.87,Dc=1.473 g/cm3,μ=0.720 mm-1,S=1.075,F(000)=866.0,the final R=0.0825 and wR=0.2149 for 2566 observed reflections(I2σ(I)).In the crystal structure,the cobalt atom adopts a distorted octahedral environment with two NCS-ions in the axial positions and two bidentate chelating L ligands in the equatorial plane.The extended 2D network of the complex is formed by intermolecular C-H…N hydrogen bonds together with π-π stacking interactions.     

Synthesis,Crystal Structure and DNA Binding Studies of α,α'-Bis(3,5-bismethyl-1-pyrozolyl)-carbene-acetyl-isopropenyl Hydrazine

The title compound α,α'-bis(3,5-bismethyl-pyrozole-N-yl)-carbene-acetyl-isopro- penyl hydrazine (C16H22N6O, Mr = 314.40) has been prepared. It was characterized by elemental analysis as well as IR, MS, 1H-NMR and 13C-NMR spectra. Its crystal structure was determined by single-crystal X-ray diffraction, getting the following data: triclinic, space group P1 with a = 6.9734(16), b = 10.773(3), c = 12.001(3) , α = 75.311(4), β = 82.695(4), γ = 77.143(4)o, Z = 2, V = 847.9(3) 3, Dc = 1.231 g/cm3, F(000) = 336 and μ(MoKα) = 0.082 mm-1 (λ = 0.71073 ). The results of crystal structure determination show that there exist intermolecular and intramolecular hydrogen bonds, resulting in a two-dimensional supramolecular framework of the title compound. The binding of the title compound to DNA was investigated by absorption, emission, and viscosity measurements. The title compound shows absorption hyperchromicity accompanied by a blue shift at about 254 nm. The binding constant Kb for the title compound has been determined to be 1.89 × 104 M-1 from absorption measurements. The addition of the title compound to DNA pretreated with EB causes appreciable reduction in the emission intensity, indicating that the DNA-bound EB fluorophore is partially replaced by the title compound. The value of K is 3.093 × 104 M-1. The relative viscosity of DNA decreased with the addition of the title compound. Results suggest that the title compound binds to DNA with a non-classical intercalative or groove interaction mode. The observed efficient nuclease activity of the title compound is interesting and may have further influences on the chemistry of DNA minor groove binders. Keywords: α,α'-bis(3,5-bismethyl-pyrozole-N-yl)-carbene-acetyl-isopropenyl, preparation, crystal structure, DNA binding     

Synthesis and Crystal Structure of 1,2-Bis-（p-nitrophenylsulfonamido）-4,5-dinitrobenzene

The title compound, 1,2-bis-(p-nitro-phenylsulfonamido)-4,5-dinitrobenzene, was synthesized and characterized by elemental analysis, IR and 1H NMR. A pale yellow prism crystal of C23H26N8O13S2 (Mr = 686.64) was obtained in DMF solution and determined by single-crystal X-ray diffraction method. It crystallizes in triclinic system, space group P1 with a = 10.346(4), b = 12.210(5), c = 12.976(5) , α = 108.220(8), β = 99.482(4), γ = 95.490(4)°, V = 1516.7(10) 3, Z = 2, Dc = 1.504 g/cm3, F(000) = 712, μ = 0.254, Mr = 686.64, the final R = 0.0561 and wR = 0.1487. One sulfonamido group of the title compound is deprotoned and forms N(3)=C(13). The crystal involves N,N-dimethylamine from the decomposition of DMF and the proton is transferred to N,N- dimethylamine. It is a strong proof for the characterization of deprotoned recognition compound by X-ray single-crystal structure.     

Synthesis,Crystal Structure and Bioactivity of N-（phenethylcarbamothioyl）cyclopent-1-enecarboxamide

The compound N-(phenethylcarbamothioyl)cyclopent-1-enecarboxamide was synthesized by the reaction of cyclopent-1-enecarbonyl isothiocyanate with phenethylamine in acetone, and its structure was characterized by IR, 1H NMR and X-ray crystal structure determination. The crystal of the title compound belongs to triclinic, space group P1 with a = 6.9500(7), b = 9.4618(9), c = 11.3256(11), α = 71.522(9), β = 81.830(8), γ = 89.237(8)o, Z = 2, V = 698.80(12)3, Dc = 1.304 g/cm3, μ = 0.225 mm-1, F(000) = 292, R = 0.0413 and wR = 0.1073 for 1996 observed reflections with I 2σ(I). Intramolecular N(2)–H(2)···O(1) interactions as well as intermolecular N(2)–H(2)···O(1), N(1)–H(1)···S(1) and C(12)–H(12)···S(1) hydrogen bonds help to stabilize the crystal structure. X-ray diffraction analysis reveals that the structure of the new compound exhibits a one-dimensional infinite chain-like structure. The cytotoxicity of the compound was investigated by MTT assay. The results show that the compound is toxic to A549 tumor cell.     

Synthesis and Crystal Structure of a Novel Ion-pair Compound Consisting of 1,3-Bis（4-cynobenzyl） Imidazole Cation and 7,7,8,8-Tetracyanoquinodimethanide Anion

A novel compound [(CNBz)2Im]2(TCNQ)3(CH3CN)((CNBz)2Im = 1,3-bis(4-cyano-benzyl) imidazole cation,TCNQ-1 = 7,7,8,8-tetracyanoquinodimethanide anion) was synthesized by the reaction of [(CNBz)2Im]Br and LiTCNQ in water and its structure was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/c with a = 10.1823(17),b = 20.292(3),c = 16.952(3) ,β = 104.73(0)°,V = 3387.6(10)3,Z = 4,C39H24N11,Mr = 646.69,Dc = 1.268 g/cm3,μ = 0.080 mm-1 and F(000) = 1340.The structure was solved by direct methods and refined to R = 0.0596 and wR = 0.0911 for 2690 observed reflections(Ⅰ 2σ(Ⅰ)).The most prominent structural feature is that there are two types of TCNQ entries(TCNQ-1 and TCNQ0) in agreement with the IR spectra analysis of the compound.     

铜锌超氧化物歧化酶与丝氨酸钴(Ⅱ)的相互作用

The effect of changing the amount of externally added cobalt(Ⅱ) serine, an organic metal compound, and the pH value of the enzyme solution on the interaction of copper zinc superoxide dismutase (Cu 2Zn 2SOD) with cobalt(Ⅱ) serine was studied by means of visible spectroscopy, inductively coupled plasma atomic emission spectrometry and measurement of enzyme activity. It was found that in aqueous solution, there exists a direct interaction of the metal ions of the active center in Cu 2Zn 2SOD with cobalt(Ⅱ) serine. As a result, part of the metal ions in the metalloenzyme were replaced by Co ion to form Co(Ⅱ) substituted derivatives of SOD and the catalytic activity of the enzyme decreased.     

Synthesis, Crystal Structure and Fluorescene of a One-dimensional Compound {CdI_2(2,2′-bipy)}_n

The title compound, {CdI2(2,2′-bipy)}n, was prepared by the hydrothermal reac- tion of CdI2 and 2,2′-bipy in an aqueous solution, and its crystal structure was determined by X-ray single-crystal analysis. Crystallographic data for 1: C10H8N2CdI2, monoclinic system, space group C2/c, a = 16.927(1), b = 10.0925(7), c = 7.7422(3) , β = 106.0629(4)°, V = 1271.00(14) 3, Z = 4, F(000) = 944, μ = 6.546 mm-1, Dc = 2.730 g/cm3, Mr = 522.38, the final R = 0.0309 and wR = 0.0805 for 1310 observed reflections (I > 2σ(I)). X-ray crystal structure analysis shows that the Cd atom is coordinated by four iodines and two N atoms from one 2,2′-bipy to form an 1-D chain-like structure through bridging iodines. The fluorescene of the title compound was also discussed.     

A novel one-dimensional organic-inorganic polymer: synthesis and crystal structure of[{Ca(DMF)_5}_2SiMo_(12)O_(40)]_n

A novel polyoxometalate-based organic-inorganic polymer [{Ca(DMF)5}2SiMo12O40]n has been synthesized and characterized by elemental analysis, IR, UV and X-ray single-crystal structural analysis. The title compound crystallizes in a monocline lattice, P21/n, with a =1.3379(3), b = 1.9796(4), c = 1.4574(3) nm, β = 92.24(3)°, V = 3.8568(13) nm3, Z = 2, R1 = 0.083 and Rw = 0.2065. The result of crystal structure analysis indicates that Ca2+ is surrounded by seven coordination oxygen atoms with pentagonal bipyramidal geometry and bridged with terminal oxygen atom of polyanion in the structure. The compound contains an unprecedented one-dimensional linear chain built by alternate polyanions and cationic units through Mo-Od-Ca-O-Ca links in crystal. The IR spectra and X-ray crystallography analysis exhibit that there is a strong interaction between the polyanion and organic group in solid state. The electronic spectra (λ = 200-500 nm) for the title compound dissolved in the mixed solvent of acetonitrile and     

Preparation and Structure of A Novel Ethanolamine-occluding Aluminoarsenate

An aluminoarsenate, Al2As2O3.EAN, denoted as AlAsO4-1 was synthesized from EAN(EAN= ethanolamine), pyroarsenic acid and aluminium-iso-propylate systems. The crystal structure of AlAsO4-1 was determined by single crystal X-ray diffraction method. The compound crystallizes in orthorhombic space group Pcab with the unit cell constants:0 = 8.781(3), 6=10.261(3), c=20. 433(11) A .V = 1840.9 A3, 2=8. The final R and Rw factors are 0. 0401 and 0. 0344, respectively. The framework of AlAsO4-1 contains two types of Al atoms. It is interesting that in the asymmetric unit one of two Al atoms is strictly 4-coordinated and the other is 6-coordinated. The three-dimensional framework is built of two-dimensional nets which consist of 4-membered rings and 8-membered rings. The biggest open channel in the framework runs along [100], in which EAN template is located. Arsenic atoms can function as a component element for construction of three-dimensional net with topological novelty.     

Synthesis, Crystal Structure and AbsoluteConfiguration of （＋）-O-Phenyl Cyclophosphorodiamidate

The title compound, ( )-O-phenyl cyclophosphorodiamidate (C28H33N202P, Mr=460.53), has been synthesized and characterized by 31p NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 273(2) K indicates that it belongs to orthorhombic system, space group P212121 with a=11.518(4), b=13.449(4), c=16.539(5)A, V=2562(1)A3, Z=4, Dc=1.194g/cm3, F(000)=984 and μ(MoKα)=0.134mm-l. The structure parameters were refined by full-matrix least-squares on F2 to R=0.0459 and wR=0.0640. The flack χ parameter is 0.03(10), and the absolute configuration of the phosphorus atom in the title compound is S.     

Kinetic Study of the Electro-Catalytic Oxidation of Hydrazine on Cobalt Hydroxide Modified Glassy Carbon Electrode

Electrocatalytic oxidation of hydrazine was investigated on a cobalt hydroxide modified glassy carbon (CHM-GC) electrode in alkaline solution. The process of oxidation involved and its kinetics were established by using cyclic voltammetry, chronoamperometry techniques as well as steady state polarization measurements. In cyclic voltammetry (CV) studies, in the presence of hydrazine the peak current increase of the oxidation of cobalt hydroxide is followed by a decrease in the corresponding cathodic current. This indicates that hydrazine is oxidized on the redox mediator that is immobilized on the electrode surface via an electrocatalytic mechanism. A mechanism based on the electrochemical generation of Co(IV) active sites and their subsequent consumption by the hydrazine in question was also investigated.