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911.
The complex [Cd(tren)(meim)](ClO4)2 was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in monoclinic system, space group P21/m with a=0.786 8(2) nm, b=0.834 2(2) nm, c=1.496 2(4) nm, Mr=538.64, Z=2, F(000)=542, Dc=1.822 g·cm-3, T=298(2) K, μ=1.435 mm-1 and λ=0.071 073 nm. The structure was refined to R=0.045 8 and wR=0.123 1 for 1 489 observed reflections with I>2σ(I). The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method. It was found to be active against the four test bacterial organisms. CCDC: 600198. 相似文献
912.
913.
1INTRODUCTIONRecently,therehasbeenconsiderableinterestinthelanthanide(III)hexacyanoferrates,theanalogoushexacyanocobaltateandhexacyanochromiumatecom-plexesbecauseoftheirpotentialapplicationsascata-lyticandsemi-conductivematerials.InitialstudiesofmetalhexacyanocobaltateswerecarriedoutbyJa-mesandWilland[1]whoreportedtheamountofhy-drationassociatedwithmicroscopiccrystalsofsever-allanthanidecomplexes.FurtherBonnetandParis[2]studiedtheLNCo(CN)6?nH2Oseries(n=4)byusinginfraredandX-raymethod… 相似文献
914.
The Schiff base‐containing pendant monoaza crown ether HL1, HL2, HL3 and HL4 have been synthesized by condensation of salicylaldehyde with N‐(4‐aminoaryl) monoaza crown ethers, which were prepared conveniently from 4‐nitro‐N, N‐di(hydroxyethyl) aniline or 4‐nitrobenzyl chloride via cyclization or condensation and reduction. The structures of HL1—HL4 were verified by 1H NMR, IR spectra, MS and elemental analysis. Moreover, the oxygenation constants (KO2) and thermodynamic parameters (δH0 and δS0) of their cobalt(II) complexes were determined in the range of ?5 °C to 25 °C, and the effect of crown ring bonded to a Schiff base on the dioxygen affinities of cobalt(II) complexes was also observed as compared to the uncrowned analogue (CoL). 相似文献
915.
《Journal of Molecular Structure》2002,616(1-3):259-264
The molecular structure of the title complex [ZnBr2(C7H6N2)2] was investigated by X-ray diffraction and IR spectroscopy methods. Molecules of zinc(II) complex crystallize in the triclinic crystal system with cell constants a=7.526(2) Å, b=7.8971(8) Å, c=13.431(1) Å, Z=2 and V=791.3(2) Å3. In the molecular structure, the Zn atom is coordinated tetrahedrally by two Br− anions and two benzimidazole ligands. Intramolecular steric repulsions between Br− anions and benzimidazole groups have been caused to cis configuration around the central metal atom. 相似文献
916.
The strictly regioselective hydrocarboxylation of vinyl acetate to ethylidene diacetate by acetic acid formed in situ from vinyl acetate was realized for the first time with Rh(PPh3)3Cl as catalyst. The transformation of vinyl acetate into benzene, acetophenone, and acetylene was also realized.Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, 420083 Ufa. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1406–1408, June, 1992. 相似文献
917.
On the Reaction of Macrocycles with Lanthanoids. I. The Crystal Structure of [Li(thf)][(C22H22N4)2Ce] · THF In THF CeBr3 forms with [(TMTAA)Li2] the paramagnetic doubledecker complex [Li(thf)][(TMTAA)2Ce]. The complex crystallizes with 1 Mol THF per formula unit. The structure was characterized by X-ray single crystal structure analysis (space group C2 (No. 5), z = 6, a = 1741.8(2) pm, b = 1622.1(2) pm, c = 2540.4(3) pm, β = 104.72(1)°). The sandwich-like arrangement of the heterocyclic ligands leads to a quadratic-prismatic coordination of the Ce3+ ion. One macrocyclic ligand is additionally coordinated by a [Li(thf)]+ fragment. The coordination of the Li ion is square pyramidal. 相似文献
918.
V. A. D’yakonov R. K. Timerkhanov A. G. Ibragimov U. M. Dzhemilev 《Russian Chemical Bulletin》2007,56(11):2232-2235
Catalytic cycloalumination of cyclonona-1,2-diene upon treatment with Et3Al and EtAlCl2 in the presence of Cp2ZrCl2, leading to 10-ethyl-10-aluminabicyclo[7.3.01,9]dodec-8-ene (1) and 11-ethyl-11-aluminatricyclo[10.7.01,12.02,10]nonadeca-9,12-diene, respectively, was accomplished in high yields. A possibility for the selective transformation of compound
1 to 1-allyl-9-(pent-4-enyl)cyclonon-1-ene and 10-hydroxybicyclo[7.3.01,9]dodec-8-ene in one preparative step was demonstrated.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2156–2159, November, 2007. 相似文献
919.
Three hexakis(imidazole)metallo complexes of Co, Cd and Ni were synthesized and spectroscopically characterized. The crystal and molecular structures have been determined by X-ray crystallography analysis. The metal ions have an octahedral geometry with the MN6 chromophore. The electrochemical experimental results indicate that both [Co(Im)6]C12·2HCl·2H2O (1) and [Ni(Im)6]C12·4H2O (3) [Im=imidazole] could interact with DNA mainly by intercalation. 相似文献
920.
Wenzel TJ Freeman BE Sek DC Zopf JJ Nakamura T Yongzhu J Hirose K Tobe Y 《Analytical and bioanalytical chemistry》2004,378(6):1536-1547
Chiral crown ethers 1 and 5 are useful enantiomeric discriminating agents in 1H NMR spectroscopy for neutral and protonated primary amines, amino acids, and amino alcohols. The presence of the carboxylic acid groups in 1 and 5 provide sites at which ytterbium(III) can bind. Adding ytterbium(III) nitrate to crown–substrate mixtures in methanol-d4 causes shifts in the spectra of substrates and often enhances the chiral discrimination in the 1H NMR spectrum. The enhancement in enantiomeric discrimination that occurs in the presence of ytterbium(III) allows lower concentrations of the crown ether to be used in chiral recognition studies. Several amide derivatives of 1 were prepared and evaluated as chiral NMR discriminating agents, although except for 1e, these were less effective than 1. 相似文献