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971.
《Journal of Coordination Chemistry》2012,65(11):1801-1808
The reactions of 2-PAMF with metal perchlorates [2-PAMF = (2-pyridylmethylamino)carbonylferrocene] yielded three coordination compounds, M(2-PAMF)2(CH3CH2OH)2(ClO4)2 (M = Co 1, Zn 2, and Cu 3), which were characterized by single crystal X-ray diffraction and IR spectroscopy. Compounds 1 and 2 have similar structures with six-coordinate metals in octahedral geometries. The CuII in 3 possesses a severely distorted octahedral geometry due to Jahn–Teller distortion. Adjacent molecules in the three compounds were linked by intermolecular hydrogen bonds to form a 1-D supramolecular chain. 相似文献
972.
《Journal of Coordination Chemistry》2012,65(21):3932-3944
Four transition metal coordination compounds, {[Co(PPDA)(H2O)2]}n (1), {[Ni(HPPDA)2]}n (2), {[Cd(PPDA)(H2O)]?H2O}n (3), and {Zn(HPPDA)2(H2O)4}n (4), were synthesized by assembling transition metal salts with a semirigid ligand 4-(pyridin-3-yloxy)-phthalic acid (H2PPDA) under hydrothermal conditions. The compounds have been characterized by elemental analyses, IR spectra, TGA, powder X-ray diffraction, and single-crystal X-ray crystallography. Compound 1 exhibits a three-connected 2-D layered structure, 2 shows a (3,6)-connected 2-D layered structure, 3 displays a (3,6)-connected 2-D layered framework based on binuclear units, and 4 is a mononuclear structure, connected to generate a 3-D supramolecular architecture by hydrogen bonds. Compound 2 is thermally stable up to 300 °C. The magnetic properties of 1 and photoluminescent properties of 3 and 4 have been explored. 相似文献
973.
974.
《Journal of Coordination Chemistry》2012,65(10):1606-1614
Three new compounds, [Cd(μ 3 -Hpdh)(μ2-Cl)] n (1), Mn(Hpdh)2(H2O)2 (2) and Zn(Hpdh)2 (H2O)2 (3) (H2pdh =?pyridine-2,3-dicarbo-2,3-hydrazide), have been synthesized and characterized by elemental analysis, IR spectra, TG and single-crystal X-ray diffraction. Under hydrothermal conditions, H2pdh is generated by an in situ acylation of H2pda (H2pda =?pyridine-2,3-dicarboxylic acid) with hydrazine hydrate. Complex 1 features a 2D layer structure constructed by a dinuclear Cd(II) building block. In complexes 2 and 3, hydrogen bonding interactions connect mononuclear structures into 3D supramolecular frameworks. 相似文献
975.
《Journal of Coordination Chemistry》2012,65(10):1622-1634
Reactions of Al(OPri)3 with LH2 =?[R′C(NYOH)CHC(R)OH] R=R′=CH3, Y =?(CH2)2 (L1H2); R =?CH3, R′ =?C6H5, Y =?(CH2)2 (L2H2); R =?R′ =?CH3, Y =?(CH2)3 (L3H2); R =?CH3, R′ =?C6H5, Y =?(CH2)3 (L4H2), in 1 : 2 molar ratio give mononuclear derivatives of aluminium AlLLH (1a–1d). Equimolar reactions of AlLLH with M(OPri)3 (M =?Al and B) yield homo- and hetero-dinuclear derivatives AlLLM(OPri)2 (M=Al=2a–2d M=B=3a–3d). Reaction of 2a with L1H2 affords AlL1L1AlL1 (4). All these derivatives have been characterized by elemental analysis, molecular weight measurements and plausible structures have been suggested on the basis of IR, NMR [1H, 13C, 27Al and 11B] spectral data and FAB-mass studies of 2b and 3b. Schiff base L1H2 and its mononuclear derivative with aluminium (AlL1L1H) have been screened for their antibacterial activity against Escherischia coli and Bacillus subtilis. 相似文献
976.
《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
977.
《Journal of Coordination Chemistry》2012,65(3):195-205
Abstract ESR investigation of the γ -ray irradiated Co(III) complexes have been carried out. The identification and the classification of the irradiation products on the basis of the ESR signal patterns, and the electronic and the spin states of the products are discussed. Co(III) complexes are reduced by the γ irradiation into Co(II) complexes, where the produced Co(II) ions have low spin configurations, S = ½. Authors refer to these particular spin states as hot ions. 相似文献
978.
《Journal of Coordination Chemistry》2012,65(18):2983-2994
Complexes of the type MLL′ · nB (where M = Ni(II) and Cu(II); LH and L′H = 2,4-pentanedione (acacH), 1-phenyl-1,3-butanedione (bacH), and 1,3-diphenyl-1,3-propanedione (dbmH); n = 0 to 2 and B = water or pyridine) have been synthesized and characterized. IR spectra are consistent with uninegative bidentate ligands. Magnetic moments and electronic spectral studies reveal high-spin octahedral geometry for nickel(II) complexes and distorted octahedral stereochemistry for copper(II) complexes. Frozen chloroform solution ESR spectra of the copper(II) complexes display significant Jahn–Teller distortion and dimeric behavior of the complexes in solution. FAB mass spectra of the copper(II) complexes also exhibit peaks corresponding to dimers. Molecular, pseudo-molecular, dimeric pseudo-molecular, and fragment ion peaks in unit resolution mass spectra have been identified with the help of their isotope distribution pattern expected due to natural abundances of the 63Cu and 65Cu isotopes. All the FAB mass spectral peaks from the fragment ions containing copper have been interpreted on the basis of isotope distribution pattern. 相似文献
979.
《Journal of Coordination Chemistry》2012,65(17):1531-1539
Two new lead(II) complexes containing nitrite, [Pb(L)2(NO2)2], L?=?1,10-phenanthroline (phen) or 2,2′-bipyridine (bpy), have been synthesized and characterized. The crystal structure of [Pb(phen)2(NO2)2] shows monomeric units. The coordination number is eight (four from “phen” ligands and four nitrite anions), weak interaction of lead(II) with oxygen atoms of adjacent molecules produce dimer units in the solid state. The arrangement of ligands exhibits a coordination hole around the lead(II), occupied possibly by a stereoactive lone pair of electrons on lead(II), and the coordination around lead is hemidirected. There is a π–π stacking interaction between the parallel aromatic rings that may help to increase the “gap” around lead(II). 相似文献
980.
Prof. Dr. Wen‐Kui Dong Yin‐Xia Sun Guo‐Hua Liu Li Li Xiu‐Yan Dong Xiong‐Hou Gao 《无机化学与普通化学杂志》2012,638(9):1370-1377
Two nickel(II) complexes, namely {[NiL(MeOH)(μ‐OAc)]2Ni} · 2CH2Cl2 · 2MeOH ( 1 ) and {[NiL(EtOH)(μ‐OAc)]2Ni} · 2EtOH ( 2 ) {H2L = 5, 5′‐dimethoxy‐2, 2′‐[(ethylene)dioxybis(nitrilomethylidyne)]diphenol}, were synthesized and structurally characterized. Two trinuclear NiII complexes are both hexacoordinate around the central NiII atoms, showing octahedral coordination arrangements, and each complex comprises three divalent NiII atoms, two deprotonated L2– ligands, in which four μ‐phenoxo oxygen atoms forming two [NiL(X)] (X = MeOH or EtOH) units, and coordinated and non‐coordinated solvent molecules. Complex 1 exhibits a 2D supramolecular network through intermolecular O–H ··· O, C–H ··· O and C–H ··· π interactions, whereas complex 2 forms an infinite 1D chain by intermolecular C–H ··· O hydrogen bonding interactions. 相似文献