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971.
《Journal of Coordination Chemistry》2012,65(4):651-662
Mixed ligand complexes of the type MLL′Cl2 (where M?=?Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II), L?=?ligand derived from the reaction between benzofuran-2-carbohydrazide and 3,4,5-trimethoxybenzaldehyde (TMeOBFC), and L′?=?ortho-phenylenediamine (opd)/2,6-diaminopyridine (2,6-dap)) have been synthesized. The complexes have been characterized by analytical data, IR, UV-Vis, 1H NMR, DART-MS and ESR spectral data, and magnetic studies. Molar conductance values indicate that the complexes are non-electrolytic in DMF. Antibacterial and antifungal activities of the ligands and complexes have been screened against bacteria Escherichia coli and Staphylococcus aureus and against fungi Aspergillus niger and Aspergillus flavus. 相似文献
972.
《Journal of Coordination Chemistry》2012,65(18):2055-2073
The complex-formation of lanthanide(III) elements with D-penicillamine have been investigated in acidic and neutral media. The macroscopic protonation constants of the ligand and the formation constants of [Ln.Pen]+, [Ln.Pen2]?, [Ln.Pen.OH] and [Ln.Pen.(OH)2]? complexes were determined from pH-metric data using the BEST computer program. Elemental analyses of the solid complexes indicate formation of 1?:?1 metal?:?ligand species. The binding sites in the complexes with the possible role of –COO?, –NH2 and –SH groups in the coordination have been discussed using infrared data. The complexes decompose in four steps as shown by their t.g. and d.t.a. analyses. A mechanism of decomposition is proposed which is supported by mass spectral data. 相似文献
973.
《Journal of Coordination Chemistry》2012,65(21):3740-3750
Complexes [M(L)(L′)Cl?·?H2O], where M?=?Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II), L?=?ligand derived from reaction between benzofuran-2-carbohydrazide and 3,4,5-trimethoxybenzaldehyde (TMeOBFC) and L′?=?2-aminothiophenol (2-atp), have been synthesized. The structures of the complexes have been proposed from analytical data, IR, UV-Vis, 1H NMR, direct analysis in real time-mass spectra, ESR spectral data, magnetic, and thermal studies. The complexes are soluble in DMF and DMSO. Molar conductance values indicate that the complexes are non-electrolytes. Antibacterial and antifungal activities of the ligands and their metal complexes have been obtained against bacteria Escherichia coli and Staphylococcus aureus and against fungi Aspergillus niger and Aspergillus flavus. 相似文献
974.
《Journal of Coordination Chemistry》2012,65(15):2411-2420
Two allomeric helical coordination polymers, {[Zn(4,4′-dps)2(HSSA)(H2O)2] · 3(H2O)} n (1) and {[Cd(4,4′-dps)2(HSSA)(H2O)2] · 3(H2O)} n (2) (4,4′-dps = 4,4′-dipyridylsulfide, H3SSA = 5-sulfosalicylic acid), have been synthesized by similar experimental methods and characterized by elemental analysis, single-crystal X-ray diffraction, and fluorescence spectra. Both crystallize in monoclinic system, space group P21/n, with a = 11.7947(13) Å, b = 13.7475(15) Å, c = 20.183(2) Å, and Z = 4 for 1 and a = 11.940(7) Å, b = 14.068(8) Å, c = 20.323(12) Å, and Z = 4 for 2. In both complexes, the metal (ZnII for 1 and CdII for 2) are six-coordinate with a N3O3 donor set in a distorted octahedron. Half of the 4,4′-dps are μ 2-bridging, linking adjacent metal centers and forming P21/n dimensional helical structures along the b-axis. Fluorescence measurements show that 1 and 2 have medium fluorescent emission at 402 and 405 nm, respectively. 相似文献
975.
We report on a simple processing procedure to retrieve the phase from spectral interferograms including a stationary-phase point. First, the numerical simulations are performed to demonstrate high precision of the phase retrieval from the spectral interferogram. Second, the feasibility of the procedure is confirmed in processing the experimental data from a dispersive Michelson interferometer comprising a cube beam splitter and a plate made of BK7 optical glass. From the retrieved spectral phase, the effective thickness of the BK7 optical glass is determined precisely. 相似文献
976.
《Journal of Coordination Chemistry》2012,65(9):1518-1524
A manganese(II) coordination polymer [Mn(TMB)2?·?H2O] n (1) (HTMB?=?3,4,5-trimethoxybenzoic acid) has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, powder X-ray diffraction analysis, spectroscopic (IR, solid state UV-Vis), and thermal methods. The crystal belongs to orthorhombic system, space group P212121, with cell parameters a?=?7.3001(8), b?=?11.4146(13), c?=?27.053(3)?Å, α?=?β?=?γ?=?90°, V?=?2254.3(4)?Å3, Z?=?4. In 1, TMB in two different coordination modes bridges six-coordinate manganese(II) centers forming a 1-D infinite chain coordination framework. The spectral and thermal properties of the complexes have also been studied. 相似文献
977.
《Journal of Coordination Chemistry》2012,65(20):3701-3717
2-Benzoylphenolato-(2,2′-((2,2-dimethylpropane-1,3-diyl)bis((nitrilo)(phenylmethylidyne)))-diphenolato-manganese(III) methanol solvate, [Mn(C31H28N2O2)(C13H9O2)]·CH3OH (1), was synthesized and characterized by FTIR, UV–vis, TG-FTIR, TG/DSC, molar conductivity, magnetic moment measurement, and quantum chemical calculations. During the synthesis, partial hydrolysis of ligand is observed. The compound was obtained as amorphous, dark-brown powder. The effects of organic solvents of various polarities on the UV–vis spectra of ligands and complex were investigated. In addition, the IR and UV–vis spectra were also calculated and compared with the experimental data. A single crystal for analysis was obtained by dissolving the amorphous complex in methanol, and slow evaporation of solvent at 4 °C. Single-crystal X-ray analysis indicated that the methanol molecules are not incorporated into the crystal lattice after the recrystallization process ([Mn(C31H28N2O2)(C13H9O2)] (2)). In the structure Mn(III) is surrounded by two nitrogens and four oxygens of deprotonated Schiff base and α-hydroxy ketone ligands, and adopts a distorted octahedral geometry. 相似文献
978.
《Journal of Coordination Chemistry》2012,65(11):1969-1985
Several mixed ligand complexes [M(II)(PN)(B)] [M(II) = Ni(II), Cu(II), and Zn(II)] derived from pyridoxine (PN) and imidazoles (B), namely imidazole (him), benzimidazole (bim), histamine (hist), and L-histidine (his), were synthesized. The complexes are characterized by elemental analysis, IR, UV-Vis 1H NMR, and ESR spectroscopy. In [M(II)(PN)B], the monovalent anion of PN is bidentate to M(II) (–O, –OH), him, bim monodentate (–N), hist bidentate (–N, –N), and his tridentate (–O, –N, –N). Magnetic moment studies showed that the Ni(II) complexes and Cu(II)–PN–his have octahedral configuration while the other Cu(II) complexes have distorted tetrahedral geometry. The g ∥/A ∥ values calculated from the X-band ESR spectra of Cu(II) complexes in DMSO at 300 and 77 K supports the geometry. The thermal behavior (TG/DTA) of the synthesized complexes indicates the presence of lattice as well as coordinated water in the complexes. The in vitro biological activity of the mixed ligand complexes was tested against common bacteria, yeast, and fungi. The results in comparison with the control indicate that most of the complexes exhibit higher biological activities. The oxidative DNA cleavage studies of the mixed ligand complexes were performed using gel electrophoresis. 相似文献
979.
《Journal of Coordination Chemistry》2012,65(20):3673-3685
Herein we report the synthesis and characterization of trans-[RuIICl2(PPh3)3] with potentially tridentate Schiff bases derived from 5,6-diamino-1,3-dimethyl uracil (H2ddd) and two 2-substituted aromatic aldehydes. In the diamagnetic ruthenium(II) complexes, trans-[RuCl(PPh3)2(Htdp)] (1) {H2tdp = 5-((thiophen-3-yl)methyleneamino)-6-amino-1,3-dimethyluracil} and trans-[RuCl(PPh3)2(Hsdp)] (2) {H2sdp = 5-(2-(methylthio)benzylideneamino)-6-amino-1,3-dimethyluracil}, the Schiff base ligands (i.e. Htdp and Hsdp) act as mono-anionic tridentate chelators. Upon reacting 5-(2-hydroxybenzylideneamino)-6-amino-1,3-dimethyluracil (H3hdp) with the metal precursor, the paramagnetic complex, trans-[RuIVCl2(ddd)(PPh3)2] (3), was isolated, in which the bidentate dianionic ddd co-ligand was formed by hydrolysis. The metal complexes were fully characterized via multinuclear NMR-, IR-, and UV–Vis spectroscopy, single crystal XRD analysis and conductivity measurements. The redox properties were probed via cyclic voltammetry with all complexes exhibiting comparable electrochemical behavior with half-wave potentials (E½) at 0.70 V (for 1), 0.725 V (for 2), and 0.68 V (for 3) versus Ag|AgCl, respectively. The presence of the paramagnetic metal center for 3 was confirmed by ESR spectroscopy. 相似文献
980.
《Analytical letters》2012,45(1-2):177-191
Abstract Simple procedures for the preparation of pure phyllohydroquinone and phylloquinone are described. Phylloquinone is reduced by sodium dithionite and the reduced vitamin is purified by reverse phase high performance liquid chromatography. The essential spectral properties of the pure vitamins in ethanol and methanol are cited. The data provide a convenient spectral method for the accurate determination of the absolute concentrations of the oxidized and reduced vitamins and the rates of oxidation of the reduced vitamin. Pure, dry phyllohydroquinone may be safely stored at -70[ddot]C under nitrogen for a period of months. The stability of Phyllohydroquinone in methanol at 25.0 ± 0.1[ddot]C is also reported. 相似文献