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1.
Complexes of the general formula, ML2 [M = CuII, NiII, CoII and OVIV; L = 1,2,3,5,6,7,8,8a-octahydro-3-hydroxyimino-N-(4-X-phenyl)-l-phenyl-5-(phenylmethylene)-2-naphthalenecarboxamide (X = H, Me, OMe, Cl)] have been prepared and characterized on the basis of elemental analysis, magnetic moments and i.r., e.p.r. and electronic spectra. These metal complexes contain the N4 chromophore with the ligand coordinating through nitrogens of the azomethine and deprotonated anilide functions. C.v. measurements indicate that the copper(II) complexes are quasi-reversible in acetonitrile solution. Square planar and square pyramidal structures are assigned respectively to the copper(II) and oxovanadium(IV) complexes, whereas tetrahedral geometry is assigned to the nickel(II) and cobalt(II) complexes. Deprotonated anilide nitrogen is involved in coordination and the presence of an electron-donating group para to the anilide function decreases the ΔE values of the d–d transitions while the value is found to increase when electron-withdrawing groups are substituted. Line spacing in the e.p.r. spectra of the copper(II) and oxovanadium(IV) complexes increases when methyl group is para to the anilide group, and decreases when this group is replaced by methoxy or chloro. The ν(C–N) of the anilide group and the ν(C-N) of the azomethine function of the oxime metal complexes are metal-sensitive and the blue shift for the above stretching frequencies follows the order: copper(II) > oxovanadium(IV) > nickel(II) ≈ cobalt(II). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

2.
A new potential tetradentate ligand, N-nicotinoyl-N-2-furanthiocarbohydrazide (H2Nfth), and its complexes with VOIV, MnII, FeII,III, CoII, NiII, CuII and ZnII have been prepared and characterized by elemental analyses, magnetic susceptibility measurements, u.v.–vis, i.r., n.m.r., ES+ and FAB mass spectral data. The room temperature e.s.r spectra of the VOIV and FeIII complexes yield g values, characteristic of octahedral complexes. The Mössbauer spectra of [Fe(HNfth)2] and [Fe2(Nfth)3] at room temperature and at 78 K suggest the presence of high-spin iron(II) and iron(III), respectively. The complexes are electrically insulating at room temperature, however, their conductivities increase as the temperature increases from 333–383 K, with a band gap of 0.46–0.77 eV, indicating their semiconducting behaviour. H2Nfth and its soluble complexes have been screened against several bacteria and fungi.  相似文献   

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A new ligand, N-phenyl-N -2-furanthiocarbohydrazide (HPhfth), and its complexes with VOIV, MnIII, FeIII, CoII, NiII, CuII and ZnII have been prepared and characterized by elemental analyses, magnetic susceptibility measurements, i.r., n.m.r., u.v.–vis., mass and FAB mass spectral data. The room temperature e.s.r. spectra of the VOIV, FeIII and CuII complexes yield <g> values characteristic of square pyramidal VOIV, octahedral FeIII and square planar CuII, respectively. The NiII and CuII complexes semiconduct, but the ZnII complex is an insulator at room temperature. However, the conductivity increases as the temperature increases from 303–383 K, with a band gap of 0.21–1.01 eV. HPhfth and its soluble complexes have been screened against several bacteria and fungi.  相似文献   

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An apparatus for heavy-current and high-tension electrophoresis on filter paper is described This apparatus enables one to avoid the difficulties that occur in electrophoresis in base electrolytes that are highly concentrated or show greater electric conductivity The zones migrate along the paper strips with constant speed and, consequently, it is possible to measure the mobility The effective length of the filter paper strips is 660 mm Correction of the apparent mobility in the porous adsorbent is treated thoroughly.Diagrams of the electrophoretic mobility of the chloro-complexes of Hg(II), Bi(III), Cd(II), Pb(II), and Cu(II) in hydrochloric acid, are given in the experimental part The concentration of the hydrochloric acid varied between 0.1N and 6N In 6N HCl all the metals investigated are present asani onic complexes. Hg, Bi.Cd, and Pb chloro-complexes show a pronounced maximum of mobility in the anionic range. The sequence of the zones in the direction anode to cathode is Hg, B1, Cd, Pb, Lu al 0.1–2.3N HCl and B1, Hg, Cd, Pb.Cu at2.3–6N HCl.Finally, the electrophoretic separation of a mixture of Hg, Bi, Cd, Pb, Cu in 1N, 2N and 4N HCl is illustrated Complete separation of the zones was achieved in each experiment  相似文献   

7.
Summary The reactions of manganese(II), cobalt(II) and nickel(II) acetates (1 mole) with antipyrine-4-azo--ethylcyanoacetate (HL1) and antipyrine-4-azo--acetylacetone (HL2) (1 mole) produce complexes of the M(L)2 type. K2PdCl4 (1 mole) reacts with HL1 and HL2 (1 mole) to yield complexes of the general formula PdLCl, the ligands behaving as monobasic tridentates. The electronic spectral and magnetic data show the complexes to be high-spin octahedral, whereas the palladium(II) complexes are diamagnetic square planar. The complexes were characterized by elemental analyses, conductance measurements and i.r. and electronic spectra as well as magnetic susceptibility measurements and thermal (t.g.a. and d.t.a.) analysis.Nuclear Material Authority.  相似文献   

8.
We have studied tin(II), tin(IV), lead(II) and lead(IV) compounds of the type M[CH(SiMe3)2]2 (5), M[N(SiMe3)2]2 (6), M[N(SiMe3)SiMe2tBu]2 (7), Me3MCH2SiMe3 (1), Me3MCH(SiMe3)2 (3), Me3MNHSiMe2tBu (2), Me3MN(SiMe3)2 (4), Me2M[N(SiMe3)2]2, (8) and (Me3M)2NSiMe2tBu (9) by 13C, 15N, 29Si, 119Sn and 207Pb NMR spectroscopy. In some cases, two-dimensional (2-D) 13C/1H and 29Si/1H heteroscalar-correlated NMR spectra served for the comparison of the signs of the respective coupling constants [nJ(M 13C), 2J(M29Si) and nJ(M1H)]. The 13C and 15N NMR parameter of comparable compounds (replacement of the CH or CH2 fragment by a nitrogen atom or the NH group, respectively), show analogous trends. In the monomeric M(II) compounds (5, 6, 7) the peculiar electronic situation at the metal is reflected by the extreme deshielding of the metal nuclei (e.g. δ207 Pb for 5b = +9110 ppm), by the strongly deshielded 13C (5) and 15N nuclei (6, 7), as well as by large negative contributions to the reduced nuclear spin—spin coupling constants 1K(M13C) (5) and 1K(M15N) (6). In the M(II) compounds 5 the 119Sn and, in particular, the 207Pb longitudinal and transverse nuclear relaxation is dominated by the chemical-shift-anisotropy mechanism. This is also true for 6 and 7, in which the transverse relaxation rate is further increased by scalar relaxation of the second kind owing to partially relaxed scalar coupling 1J(M14N).  相似文献   

9.
The dependence was investigated of the mobilities of the chloro-complexes of Hg(II), Cd(II), Pb(II) and Cu(II) on the concentration and the volume of the metal salt solution applied, the experiments being carried out in relatively low concentrations of hydrochloric acid (0.1N, 0.5N and 1N) This dependence is considerable in base clectrolytes of low concentration (Iess than 1N HCl) and insignificant in the case of higher concentrations (greater than 1N HCl)On increasing the concentration and volume of the metal salt applied, the Caitionic mobility of the zones increases and the amonic mobility decreasesUnder certain conditions chloro-, bromo-, and lodo-complcxcs of cadmium showed multispots Wc have occasionally obbcived these multispotsalsom the cicctrophorcsis of other metal complcKCb  相似文献   

10.
Thermodynamics of complexation reactions between Zn(II), Ni(II), Hg(II), Co(II), and Cu(II) acetates and 3,35,5-tetramethyl-4,4-dibutyldipyrrolylmethene in DMF at 298.15 K is studied by calorimetric and spectrophotometric methods. The replacement of Zn2+, Ni2+, and Hg2+ ions by Co2+ and Cu2+ ions was found to increase the equilibrium constants of reactions of complex formation with dipyrrolylmethene by more than two orders of magnitude. The role of solvation interactions in coordination of dipyrrolylmethene by d-metal ions is established.  相似文献   

11.
Coordination polymers of Cr(III), Mn(II), Fe(II), Co(II), Ni(II), and Cu(II) with a Schiff base derived from 4,4′ - (4,4′ -biphenylylene bisazo) di (salicylaldehyde) and m-toluidine have been prepared. All the polychelates are dark colored and insoluble in common organic solvents. Magnetic susceptibility and electronic and IR spectra of the polychelates have been studied. All the polychelates except Cu(II) show octahedral structures while Cu(II) polychelate is suggested to be a square planar.  相似文献   

12.
Divalent metal complexes of N,N′-bis(4-imidazolymethyl)etylenediamine (EMI) have been studied using potentiometric and spectroscopic techniques (UV-Vis and NMR methods) in aqueous 0.1 mol⋅L−1 KCl supporting electrolyte at 25 °C. Final models and overall stability constants for the complexes of Ca(II), Cd(II), Co(II), Cu(II), Mg(II), Mn(II), Ni(II), Pb(II) and Zn(II) have been established by potentiometry for all M(II)–EMI systems, except for Co(II)–EMI. The data revealed that EMI forms ML complexes with all M(II)–EMI systems, which is the dominant species over a wide range of pH except for the Ca(II)–EMI and Mg(II)–EMI systems. Formation of the MnHL complex was also found for Mn(II)–EMI solutions. In addition, the UV-Vis and 1H NMR results allowed us establish the coordination modes for the metal complexes between EMI with Cd(II), Cu(II), Ni(II) and Zn(II).  相似文献   

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15.
The reactions of complex formation of Cu(II), Co(II), Zn(II), Ni(II), and Cd(II) acetates with 3,3′,4,4′5,5′-hexamethyl-2,2′-dipyrrolylmethene (HL) in DMF were studied by the electronic spectroscopy and calorimetric titration methods at 298.15 K. The main products of the above reactions are [ML2] chelates. In the case of Cu and Ni salts, the process occurs through the spectrally recorded stage of formation of the heteroligand [ML(AcO)] complexes. The reaction with Cd acetate terminates at the stage of the heteroligand complex formation due to the large radius and decreasing electron affinity of the Cd2+ ion. The effect of the metal nature appears in the increasing thermodynamic stability of single-type complexes in the series [ML2]: Ni(II) < Zn(II) < Co(II) < Cu(II) and [ML(AcO)]: Cd(II) < Ni(II) < Cu(II).  相似文献   

16.
The formation of bimetallic Pd(II) and M = Fe(III), Ti(IV), V(V), Co(II), or Cu(II) complexes with the two-vacancy [As2W19O67(H2O)]14? heteropolyanion (HPA) (below referred to as As2W19) has been studied by UV/Vis and IR spectroscopy and differential dissolution. In an aqueous solution at pH 6 and a Pd: M: As2W19 molar ratio of 1: 1: 1, heteropoly complexes (HPC) incorporating two different metals one being Pd(II) are formed. The resulting complexes were precipitated from solution as cesium salts. In the case of Pd(II) and M = Fe(III), Co(II), or Cu(II) ions, the precipitate contained bimetallic HPC [As2W19FePDO67(H2O)2]9? (65.9 wt %), [As2W19CoPdO67(H2O)2]10? (45.6 wt %), and [As2W19CuPdO67(H2O)2]10? (50.7 wt %) mixed with monometallic HPC [As2W19M2O67(H2O)2](14 ? 2m)? (As2W19M2). In the case of Pd(II) and Ti(IV) or V(V), bimetallic HPC of a different composition were precipitated, namely, [As2W19Ti2O67(OH x )2 PdO](10 ? 2x)? (76.8 wt %) and [As2W19V2O67(OH x )2 PdO](8 ? 2x)? (15.0 wt %), where palladium ions are not incorporated in the HPC structure but are attached to the HPC surface, possibly, as hydroxide species. Using M = Pd(II), Ti(IV), V(V) ions and the HPA As2W19 ([M]: [As2W19] = 2 : 1, pH 6), new monometallic HPC, [As2W19Pd2O67(H2O)2]10?, [As2W19Ti2O67(OH x )2](10 ? 2x)?, and [As2W19V2O67(OH x )2](8 ? 2x)? (x = 0, 1, or 2), were obtained.  相似文献   

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Complexes [ML2] of cobalt(II), nickel(II), copper(II), zinc(II), and cadmium(II) with asymmetrically substituted (E)-3-ethyl-5-[(4-iodo-3,5-dimethyl-2H-pyrrol-2-ylidene)methyl]-2,4-dimethyl-1H-pyrrole (HL) have been prepared and characterized for the first time. The spectral properties, stability in solutions and in the solid phase at elevated temperature of the complexes have been studied. The effects of complexing metal ion and the reaction medium on the spectral luminescent properties (absorptivity, quantum yield, fluorescence lifetime, and the radiation constant) and on thermal destruction of the [ML2] complexes have been discussed.  相似文献   

19.
20.
The preparation and characteristics of a new water-soluble reagent, N-phenyl- N'-(sodium p-aminobenzenesulfonate)thiourea (PPT) are described. In the presence of cetyltrimethylammonium bromide (CTMAB) PPT reacts with Au(III), Pd(II), and Pt(IV) to form colored complexes with absorption maxima at 317 nm, 306.1 nm, 778.4 nm, respectively. Optimum conditions for color development were studied. The reagent was used for the simultaneous determination of Au(III), Pd(II), and Pt(IV); Amberlyst A-26 macropore anion-exchange resin was used as a means of rapid separation. The method was applied to the determination of Au(III), Pd(II), and Pt(IV) in catalyst materials and anode mud with satisfactory results.  相似文献   

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