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971.
972.
K. A. Volkova V. N. Elokhina A. S. Nakhmanovich L. I. Larina A. I. Albanov 《Chemistry of Heterocyclic Compounds》2006,42(10):1343-1345
The reaction of benzoyl(2-furoyl)hydrazines with 1,3-dibromopropyne on heating in acetonitrile in 1:1 or 1:2 ratio of the
reagents gave exclusively substituted 2-phenyl(2-furyl)-1,3,4-oxadiazine hydrobromides.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1555–1557, October, 2006. 相似文献
973.
当入射氦原子能量E=0.1 eV时,用密耦方程(Close Coupling Equation)计算非对称同位素替代分子HD、DH-He碰撞的弹性和非弹性散射的角分布. 相似文献
974.
975.
Pankaj Sharma Noe Rosas Armando Cabrera M. J. Silva Hernandez Alfredo Toscano Simn Hernndez Rene Gutierrez 《应用有机金属化学》2005,19(10):1121-1126
New stibine and bismuthine substituted thienyl ring compounds, i.e. tris(3‐methyl‐2‐thienyl)stibine (1), tris(3‐methyl‐2‐thienyl)bismuthine (2), tris(3‐thienyl)stibine (3), tris(3‐thienyl)bismuthine (4) and tris(5‐chloro‐2‐thienyl)stibine (5), have been synthesized and characterized by IR, mass, 1H, 13C, COSY, and HETCOR NMR spectroscopy. The metal centres in all compounds are pyramidal, and molecules in the stibine compound (1) and bismuthine compound (2) associate via Sb···S or Bi···S interactions to form supramolecular chains. The cytotoxicity of compounds 1 and 5 was determined. For compound 5, 85% of carcinogenic cell growth inhibition (U, K and H) was observed. Compound 1 shows a significant selectivity (>80%) for carcinogenic cell growth (K and U) inhibition. Both the compounds are highly toxic for the growth of normal lymphocytes with ~95% lethality. Compound 1 is approximately 20 times more toxic than 5 against Artemia salina. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
976.
In this paper, eighteen aryl substituted semicarbazide underwent efficient oxidation to aryl azo compounds using NaNO2/NaHSO4·H2O/SiO2 under mild conditions with excellent yields. 相似文献
977.
978.
979.
The reaction of copper metal with various substituted benzyl bromides in dimethylformamide has been studied and the kinetic and thermodynamic parameters of the reaction have been obtained. Hammett plots of log(k/k°) vs the substituent constant σ gave good correlations (ρ = 0.24, Sρ = 0.03, r = 0.951). The structure of the organic group has little effect on the rate of reaction of substituted benzyl bromides with copper. In the absence of atmospheric oxygen, oxidative dissolution of copper occurred by the mechanism of single‐electron transfer with the formation of 1,2‐diphenylethanes and copper(I) complexes. The stereochemistry and intermediate compound were also studied and the reaction mechanism is discussed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
980.
Jianhui Hou Benhu Fan Lijun Huo Chang He Chunhe Yang Yongfang Li 《Journal of polymer science. Part A, Polymer chemistry》2006,44(3):1279-1290
Two alkylthio‐substituted poly(p‐phenylenevinylene) (AT–PPV) derivatives, poly(2‐octylthio‐p‐phenylenevinylene) (OT–PPV) and poly[5‐methoxy‐2‐(2′‐ethyl‐hexylthio)‐p‐phenylenevinylene] (MEHT–PPV), were synthesized by a Heck coupling reaction for the investigation of the effect of alkylthio groups on the optoelectronic properties of poly(p‐phenylenevinylene) derivatives. The absorption peaks of OT–PPV and MEHT–PPV solutions were located at 431 and 438 nm, respectively. As for solid films, an OT–PPV film showed an absorption maximum wavelength at 444 nm, 13 nm redshifted in comparison with its solution value, whereas an MEHT–PPV film displayed the same absorption peak position as its dilute solution; this indicated that there was no interchain interaction in the MEHT–PPV film. Polymeric light‐emitting diodes (PLEDs) and polymer solar cells (PSCs) based on OT–PPV and MEHT–PPV were fabricated and characterized. Very narrow bandwidths of the electroluminescence (EL) spectra of the two AT–PPVs were found, with the full width at half‐maximum of the emission being 40 and 47 nm for OT–PPV and MEHT–PPV, respectively. The maximum EL efficiency of the single‐layer PLED based on MEHT–PPV with Al as a cathode reached 1.49 cd/A. The PSC based on a blend of OT–PPV and [6,6]‐phenyl‐C61 butyric acid methyl ester (PCBM) showed the power conversion efficiency of 1.4% under the illumination of AM1.5 (80 mW/cm2). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1279–1290, 2006 相似文献