Spectroscopic Studies on Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ) Complexes with 4,4'-Bipyridine

Fourier-transform infrared(FTIR),Raman and ultraviolet-visible spectra of 4,4'-bipyridine and its me-tal-organic coordination compounds synthesized from 4,4'-bipyridine and nitrate of Co(Ⅱ),Ni(Ⅱ) and Zn(Ⅱ) were measured and analyzed,respectively.The main FTIR and Raman bands were assigned in detail.The relationship between these characteristic bands and the structure of ligands and coordination compounds were discussed.     

Syntheses,Crystal Structures and Properties of Mn(Ⅱ) and Co(Ⅱ) Coordination Complexes Based on 1,10-Phenanthroline Derivative

Two new coordination complexes[Mn(L)₂(DNSA)](1) and[Co(L)(1,4-bdc)]_n (2) have been achieved under hydrothermal conditions (H₂DNSA=3,5-dinitro-salicylic acid,1,4-bdc=1,4-benzenedicarboxylic acid and L=2-(2-fluoro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline).1 crystallizes in monoclinic,space group P2_1/c with a=15.871(3),b=17.274(4),c=16.078(3)A,β=113.03(3)^o,V=4056.6(16)A³,Z=4,C₄₅H₂₂Cl₂F₂Mn N₁₀O₇,M_r=978.57,D_c=1.602 g/cm³,F(000)=1980,μ(Mo Ka)=0.536 mm^–1,R=0.0437 and w R=0.1065.2 belongs to the monoclinic system,space group C2/c with a=14.665(2),b=30.856(4),c=11.237(2)A,β=111.166(2)^o,V=4742.0(12)A³,Z=8,C₂₇H₁₄Cl Co FN₄O₄,M_r=517.80,D_c=1.602 g/cm³,F(000)=2312,μ(Mo Ka)=0.889 mm^–1,R=0.0364 and w R=0.0862.The central Mn(II) ion in 1 is six-coordinated by four nitrogen atoms from two L ligands and two oxygen atoms from one DNSA anion.In 2,the two kinds of 1,4-bdc ligands link neighboring Co(II) atoms to yield a two-dimensional layer structure.The luminescence of 1 has been studied in detail.Moreover,thermal behaviors of 1 and 2 are also investigated.     

Syntheses,Crystal Structures and Magnetic Studies of Two Mn(Ⅱ) Complexes Based on 2-Pyrimidineamidoxime

Two novel manganese(Ⅱ) complexes, [Mn(pmadH_2)_2(3-Sb)]n(1) and {[Mn(pmadH2)(Hssal)(H_2O)]·2 H_2O}n(2)(pmadH_2= 2-pyrimidineamidoxime, 3-Sb = 3-sulfobenzoate dianion, H_3ssal = 5-sulfosalicylic acid), have been successfully obtained. The two complexes were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermal gravimetric analysis, infrared spectra and elemental analysis. They are one-dimensional manganese polymer(1) and two-dimensional manganese complex(2), respectively. The values of χmT at 300 K of 1 and 2 are lower than the spin-only value for the non-interacting Mn(Ⅱ) ion(S = 5/2).     

Syntheses,Crystal Structures and DNA-binding Properties of Cd(Ⅱ), Co(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ) Complexes Containing Imidazolium Derivatives

Cd(Ⅱ), Co(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ) complexes(1~4) based on 2-(2-pyridyl)benzimidazole(pbm) and 4,4'-oxybisbenzoic acid(H2odc) were synthesized. The formulas of these complexes are [Cd(pbm)(odc)2](1), [Co(pbm)(odc)2](2), [Cu(pbm)(odc)2](3) and [Zn(pbm)(odc)2](4) confirmed by single-crystal X-ray diffraction analysis, which shows that complexes 1, 2 and 4 belong to monoclinic system with space group P21/n, while complex 3 belongs to monoclinic system with space group P21/c. The binding properties of complexes 1~4 with CT-DNA are evaluated by ultraviolet spectrum, fluorescence spectra and viscosity measurements. The results indicate that complexes 1~4 have strong interaction with CT-DNA binding. These complexes exhibit an electrostatic or groove mode in respect of binding with DNA, which can effectively destroy DNA. And this binding mode may be applied to the interaction between the complexes and cancer cell DNA. Therefore, we hope to provide a theoretical and scientific basis for the research of anti-cancer drugs.     

Two Cd(Ⅱ) and Cu(Ⅱ) Complexes Based on 1-Butylbenzimidazole: Crystal Structures and Weak Interactions

1-Butylbenzimidazole L reacted with Cd(NO3)2·4H2O to afford complex [CdL(NO3)3H2O]·[HL] 1. The heptacoordinated Cd(Ⅱ) center adopts a distorted pentagongal bipyramidal geometry, and complex [CdL(NO3)3H2O]-entity and the protonated benzimidazium salt [HL]+ are connected via N-H···O hydrogen bond to form a dimeric unit [CdL(NO3)3H2O]·[HL]. A 3-D supramolecular network of 1 is formed through N-H···O and O-H···O hydrogen bonds together with π-π stacking interactions. Reaction of L with CuCl2 afforded a mononuclear complex, [CuL2Cl2] 2, in which the tetracoordinated Cu(II) center adopts a distorted tetrahedral geometry. In contrast, 2-D supramolecular layers of 2 are formed by C-H···Cl hydrogen bonds. The fluorescent emission spectra of L, 1 and 2 are described.     

Competitive bulk liquid membrane transport of Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Cd(Ⅱ),Ag(Ⅰ),Cu(Ⅱ)and Mn(Ⅱ),cations using 2,2'-dithio(bis)benzothiazole as carrier

A series of competitive metal-ion transport experiments has been performed.Each involved transport from an aqueous source phase across an organic membrane phase into an aqueous receiving phase.The source phase contained equimolar concentration of Co（Ⅱ）,Ni（Ⅱ）,Zn（Ⅱ）,Cd（Ⅱ）,Ag（Ⅰ）,Cu（Ⅱ） and Mn（Ⅱ） metal cations.The transport experiments of metal cations were carried out by 2,2’-dithio（bis）benzothiazole（DTB） in chloroform（CHCl₃）.The source phase being buffered at range pH of 4-6.5 and receiving phase being buffered at pH 3.The obtained results show that the selectivity and the efficiency of Ag（I） transport from aqueous solutions are observed in this investigation.The effect of concentration of palmitic acid in the transport efficiency of Ag（Ⅰ） ion was also conformed.     

Syntheses and Anti-lung Cancer Activities of Zn(Ⅱ) and Cu(Ⅱ) Complexes Based on Triazole and Tetrazole,respectively

The reactions of 4H-1,2,4-triazole(Htrz) with ZnCl_2, 1H-tetrazole(Htez) and Cu(NO_3)2·6H_2O afford two novel coordination polymers respectively, {[Zn_2(trz)_2(ox)](H_2O)_3}n(1) and {[Cu_3(tez)_3(OH)_2(H_2O)_2](NO_3)(DMF)_4}_n(2)(H_2ox =(COOH_)2, DMF = N,N-dimethylformamide). 1 shows 1D channels along the a axis filled with water molecules and 2 features a 2D bi-layered framework based on trinuclear Cu(II) units bridged by two μ3-OH groups. In addition, in vitro antitumor activities of compounds 1 and 2 on four human lung cancer cells(16HBE, NCI-H1299, NCI-H460 and NCI-H292) were further determined.     

Synthesis and Structural Studies of Some β-Diketone Phenylhydrazones and their Complexes with Co(II), Ni(II), and Cu(II)

Summary.  New β-diketone phenylhydrazones prepared by condensation of substituted 3-arylidene-2,4-pentanediones with phenylhydrazine, have been characterized by their elemental analyses, IR, ¹H NMR, and mass spectra. Some complexes of these Schiff bases with Co(II), Ni(II), and Cu(II) ions have been synthesized; in addition to the above methods, their structures were studied by magnetic susceptibility and thermogravimetry measurements. Received January 26, 2000. Accepted (revised) April 14, 2000     

Detection of NO2 Based on 4-Carboxyl-4'-hydroxy Azobenzene and Its Cu(Ⅱ) Complex

<正>An organic ligand and its Cu(II) complex formulated as (C_(13)H_(10)N_2O_3)·5H_2O (H_2L·5H_2O, 1) and Cu(HL)_2(phen)·0.125H_2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) have been synthesized and structurally characterized by single-crystal X-ray diffraction. In the two compounds, H_2L and HL exhibit a trans-conformation. Complex 2 shows a mononuclear Cu(II) structure with the hydroxyl group of HL uncoordinated. Complex 2 is assembled into a three-dimensional (3D) supramolecular architecture by hydrogen bonds and π-π stacking interactions. H_2L and compound 2 can detect NO_2 via reversible and irreversible color changes, respectively. The mechanism for the color changes is investigated.     

Coordination Modes of Polypyridyl Quinoxaline with Hg(Ⅱ),Pb(Ⅱ),Co(Ⅱ) and Mn(Ⅱ)

The interaction of metal ions(Hg~(2+),Pb~(2+),Co~(2+),Mn~(2+)) with polypyridyl quinoxaline ligand 2,3,6,7,10,ll-hexakis(2-pyridyl)dipyrazino[2,3-f:20,30-h]quinoxaline(HPDQ) was investigated,and four new complexes have been synthesized and characterized.Complex 1 exhibits a 0dimensional dual-core structure,2 is a one-dimensional chain structure based on a dual-core Pb unit,while 3 and 4 show a 0 dimensional single-core structural unit.Complex 1 is of monoclinic system,space group C2/c with a = 19.211(4),b = 23.896(5),c = 12.698(3) ?,β= 120.11(3)°,V= 5043.0(17)?~3,Z = 4,S = 1.053,F(000) = 2976,R~a = 0.0637 and wR~b = 0.1068(I 2σ(I)).Complex 2 adopts triclinic system,space group P1 with a = 10.370(2),b = 12.195(2),c = 21.033(4) ?,α = 80.87(3),β= 81.22(3),γ = 82.38(3)°,V= 2579.3(8) ?~3,Z = 2,S = 1.099,F(000) = 1328,R~a = 0.0609 and wR~b =0.1365(I 2σ(I)).Complex 3 is of monoclinic system,space group Cllc with a = 14.166(3),b =16.621(3),c = 20.248(4) ?,β = 92.18(3)°,V= 4764.0(16) ?~3,Z = 4,S = 1.005,F(000) = 2108,R~a =0.0589 and wR~b = 0.1332(I 2σ(I)).Complex 4 belongs to the monoclinic system,space group C2/c with a = 14.404(3),b = 16.626(3),c = 20.346(4) ?,β = 92.43(3)°,V= 4868.2(17) ?~3,Z = 4,S= 1.068,F(000) = 2108,R~a = 0.0833 and wR~b = 0.1591(I 2σ(I)).Furthermore,the behavior of HPDQ with Hg~(2+),Pb~(2+),Co~(2+) and Mn~(2+) in the solution was also investigated,and the result shows after the metal ions were added respectively,the emission of all solutions shows fluorescence quenching and has a red shift compared with that of the HPDQ ligand.     

Syntheses,Crystal Structures and DNA-Binding Properties of Zn(Ⅱ)and Mn(Ⅱ)Complexes Based on Imidazole Derivatives and Carboxylic Acid

Complexes[Zn(pbm)(5-hip)3](1),[Zn(pbm)(5-nip)3](2),[Mn(pbm)(H3btc)2(H2O)](3)and[Mn(pbm)(5-nip)3](4),where H2HIPA=5-hydroxyisophthalic acid,H2nip=5-nitroisophtha...     

Mononuclear and Binuclear Fe(III), Co(II), Ni(II), and Cu(II) Complexes of 3,4′-Dihydroxyazobenzene-3′,4-dicarboxylic Acid and 3-Carboxy-4-hydroxyphenylazo-3-carboxy-4-hydroxynaphthalene

Fe(III), Co(II), Ni(II), and Cu(II) complexes of the title azodyes have been synthesized and characterized by elemental analysis, molar conductance, TGA, DTA, magnetic susceptibility measurements, IR, electronic and ESR spectral studies. The spectral studies suggest an octahedral geometry for Fe(III) and Co(II) complexes but a square planar geometry for Ni(II) and Cu(II) complexes. The kinetics of the catalysed oxidation of N,N,N,N-tetramethyl-p-phenylenediamine dihydrochloride (TMPPD) with mononuclear and binuclear copper complexes were studied to check the activity of these copper complexes in oxidizing organic amines. The electrochemical behaviour of the metal complexes was studied using DC polarography and cyclic voltammetry. Antimicrobial activity of the azo compounds and its complexes have been tested against different microorganisms.     

Mononuclear and Binuclear Fe(III), Co(II), Ni(II), and Cu(II) Complexes of 3,4′-Dihydroxyazobenzene-3′,4-dicarboxylic Acid and 3-Carboxy-4-hydroxyphenylazo-3-carboxy-4-hydroxynaphthalene

Summary. Fe(III), Co(II), Ni(II), and Cu(II) complexes of the title azodyes have been synthesized and characterized by elemental analysis, molar conductance, TGA, DTA, magnetic susceptibility measurements, IR, electronic and ESR spectral studies. The spectral studies suggest an octahedral geometry for Fe(III) and Co(II) complexes but a square planar geometry for Ni(II) and Cu(II) complexes. The kinetics of the catalysed oxidation of N,N,N,N-tetramethyl-p-phenylenediamine dihydrochloride (TMPPD) with mononuclear and binuclear copper complexes were studied to check the activity of these copper complexes in oxidizing organic amines. The electrochemical behaviour of the metal complexes was studied using DC polarography and cyclic voltammetry. Antimicrobial activity of the azo compounds and its complexes have been tested against different microorganisms.     

Mixed Ligand Complexes of 5-arylazo-8-hydroxyquinoline and α-amino Acids with Co(II), Ni(II) and Cu(II)

Ten mixed ligand complexes of the type [M(X-QA)(aa)] and [Ni(X-QA)₂(Haa)(H₂O)],where X-HQA=5-arylazo-8-hydroxyquinoline derivatives, M=Co(II) orCu(II) and Haa=glycine (gly), alanine (ala) or methionine (met), have been prepared. The complexes have been characterized by elemental analysis, IR and electron spectra and thermal analysis. A tetrahedral structure has been proposed for the cobalt(II) and copper(II) complexes with bidentate coordination of amino acids. The nickel(II) complexes have been assigned an octahedral structure with the amino acids acting as monodentate ligands. The thermal behaviour of the complexes has been studied before and after γ-irradiation. This revised version was published online in August 2006 with corrections to the Cover Date.     

The solid state reactions of o-aminobenzoic acid with Zn(Ⅱ), Cu(Ⅱ), Ni(Ⅱ), Mn(Ⅱ) acetate hydrate at room temperature

The solid-solid state reactions of o-aminobenzoic acid with Zn(OAc)2.2H2O, Cu(OAc)2 .H2O, Ni(OAc)2.4H2O and Mn(OAc)2.4H2O result in the formation of corresponding complexes M(OAB)2 (M = Zn(Ⅱ), Cu(Ⅱ), Ni(Ⅱ), Mn(IⅡ)). XRD, IR and elemental analysis methods have been used to characterize the solid products. The activation energies of these reactions, which are calculated from the kinetic data obtained by means of the isothermal electrical conductivity measurement method, have been found to increase in the order: Cu(OAc)2.H2O(37.7 kJ.mol-1)~Mn(OAc)2.4H2O (39.7kJ.mol-1) < Zn(OAc)2.2H2O (56.3 kJ.mol-1) < Ni(OAc)2.4H2O (85.2 kJ.mol-1). The trend is related to their crystal structures.     

Synthesis and Characterization of Dipeptide Schiff Base Complexes of Copper(Ⅱ), Zinc(Ⅱ), Nickel(Ⅱ) and Cobalt(Ⅱ)

N-saliCylidenchnoacidcomplexesInayserveasmodelsfOrN-bodoXylidenedoacidcomp1exSystmschcharebelieVedtObetheintermediatesinthetranboIlationprocessl'l.ThecoordinaionOfametaJiontosuchSchiffbasesstabilizestheazomethine1inkag,underconditionsthatwouldothendsepromotebondcleaVag[2-5].Inaddition,thecomplexesOftalnoeddScAfbasesareconsideredtobeanewldndOfpoentialanhbactrialandanhcanceragentsl6].However,littleattentionhasbeengiventoSystemsinwhchtheScusbasesarederivedfromsimPlepePtides.ThispoprrePO…     

Crystal Structures of Cu(Ⅰ) and Cu(Ⅱ) Complexes of Tris(N-n-propylbenzimidazol-2-ylmethyl)amine

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Thermal behaviors of N-pyrrolidine-N′-(2-chlorobenzoyl)thiourea and its Ni(II), Cu(II), and Co(III) complexes

The N-pyrrolidine-N??-(2-chlorobenzoyl)thiourea, HL, and their Ni(II), Cu(II), and Co(III) complexes (NiL₂, CuL₂, and CoL₃) have been synthesized and characterized. The thermal decomposition reactions of all the compounds have been investigated by DTA/TG combined systems. The mass spectroscopy technique has been used to identify the products during pyrolytic decomposition. The pyrolytic final products have been analyzed by X-ray powder diffraction method. After comparison of thermogravimetric and mass results of HL, NiL₂, CuL₂, and CoL₃, the decomposition mechanism of these compounds have been suggested. The thermal stability of the Ni(II) and Cu(II) complexes according to the thermogravimetric curves follows the sequence: NiL₂?<?CuL₂. The values of the activation energy, E _a, have been obtained using model-free (Kissenger?CAkahira?CSunose, KAS, Flyn?CWall?COzawa, FWO, and Isoconversional) methods for all decomposition stages. The E _a versus the extent of conversion, ??, plots show that the values of E _a varies as ??. Thirteen kinetic model equations have been tested for selecting correct reaction models. The optimized value of E _a and Arrhenius factor, A, have been obtained using the best model equation. The thermodynamic functions (??H*, ??S*, and ??G*) have been calculated using these values.     

Syntheses,Crystal Structure and Luminescent Properties of a Novel Mn(Ⅱ) Coordination Polymer Based on 1,3,5-Benzenetricarboxylic Acid

Coordination polymers are a novel class of crystalline materials, which have attracted a huge amount of interest in recent decades. We selected an organic ligand 1,3,5-benzenetricarboxylic acid(H_3 BTC) to assemble with Mn(Ⅱ) ions to construct a novel Mn(Ⅱ) coordination polymer crystal material(namely complex 1). The resultant sample was successfully synthesized under the solvothermal reaction. Complex 1 possesses a three-dimensional(3D) framework based on two different Mn(Ⅱ) clusters: [Mn_4(COO)_8] and [Mn_2(COO_4)]. Furthermore, the resultant sample can be characterized in detail by powder X-ray diffraction(PXRD), Fourier-transform infrared spectra(FT-IR), thermal gravimetric analyses(TGA), elemental analysis(C, H and N) and luminescence.     

Synthesis and Properties of u-Oxamido Heterobinuclear Cu(Ⅱ)-Co(Ⅱ) Complexes

Three heterobinuclear complexes were synthesized, namely [Cu (oxpn) Co (L)2] (ClO4)2·xH2O(L= 2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen) , and 5-nitro-1, 10-phenanthroline (NO2-phen)), where oxpn represents N, N'-bis(3-aminopropyl) oxam-ido. Based on 1R, elemental analysis, conductivity measurement and electronic spectra, these complexes were characterized by an extended oxamido-bridged structure with Cu(Ⅱ) in a planar environment and Co(Ⅱ) in a octahedral environment. The symmetry of the cation is very close to C2v.The complexes were also characterized with variable temperature (4~300K) magnetic susceptibility, and the data were fit for the susceptibility equation derived from spin Hamilton, H= -2JS1.S2-DSx12 by least square strategy. The exchange integral, J, was found to be -22.36 cm-1 (for bpy);-15.45 cm-1 (for phen); -19. 10cm-1(for NO2-phen), indicating that there is a weak antiferromagnetic spin-exchange interaction between the metal ions.