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971.
Nan Yan FU Xue Mei ZHAO Yao Feng YUAN Ji Tao WANGDepartment of Chemistry National Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 《中国化学快报》2003,(10)
The reductive deoxygenation of aldehydes and ketones into the corresponding alkanes is accomplished by LiAlH4, in the presence of Lewis acid InBr3. It provides a convenient method to complete the transformation from carbonyl compounds to alkanes. 相似文献
972.
Depolymerization of Poly(bisphenol A carbonate) in Subcritical and Supercritical Toluene 总被引:1,自引:0,他引:1
Zhi Yan PAN Zhen BAO Ying Xu CHEN 《中国化学快报》2006,17(4):545-548
The depolymerization of poly(bisphenol A carbonate)(PC) in subcritical and supercritical toluene was studied. The experimental parameters, which influence the depolymerization reaction such as temperature (570-633 K), pressure (4.0-7.0 MPa), reaction time (5-60 min), and toluene to PC weight ratio (3.0-11.0), were investigated, and the reaction products were determined by GC, GC/MS and FT-IR spectrometer. It was found that the main product of the depolymerization reaction was bisphenol A(BPA). BPA accounted for over 55.7% of the depolymerization products at reaction temperature 613 K, pressure 5.0-6.0 MPa, reaction time 15 min and toluene/PC weight ratio of around 7.0. 相似文献
973.
Beeler AB Acquilano DE Su Q Yan F Roth BL Panek JS Porco JA 《Journal of combinatorial chemistry》2005,7(5):673-681
The synthesis of complex macrodiolides involving microwave-accelerated transesterification of chiral, nonracemic, hydroxy esters is described. Methodology development studies indicate that both microwave power and reaction temperature play an important role in the efficiency of cyclodimerizations. Hydroxy ester monomer pairs were evaluated using an analytical rehearsal leading to the preparation of a 127-member library of highly diverse and stereochemically well-defined macrodiolides. Preliminary assays identified a novel macrodiolide antagonist of the kappa opioid receptor. 相似文献
974.
Ni Yan Jiale Song Fengyan Wang Longwang Kan Jiahang Song Weiling Wang Wenqiang Ma Weidong Zhang Gang He 《中国化学快报》1990,30(11):1984-1988
Two highly emissive pyrenoviologen derivatives were synthesized and used to fabricate fluorescent sensors for detection of picric acid (PA) with good sensitivity and selectivity. 相似文献
975.
Ellison M Ball M Brabson B Budnick J Caussyn DD Chao AW Collins J Curtis SA Derenchuk V Dutt S East G Ellison T Friesel D Gabella W Hamilton B Huang H Jones WP Lamble W Lee SY Li D Minty MG Nagaitsev S Ng KY Pei X Rondeau G Sloan T Syphers M Tepikian S Yan Y Zhang PL 《Physical review letters》1993,70(5):591-594
976.
Zhou HB Wang SP Dong W Liu ZQ Wang QL Liao DZ Jiang ZH Yan SP Cheng P 《Inorganic chemistry》2004,43(15):4552-4554
A novel complex, [[CoAu2(CN)4(NITpPy)2(H2O)2]]n, 1, containing the cobalt(II) ion, dicyanoaurate(I) anion, and nitronyl nitroxide radical building blocks, has been prepared and structurally characterized by single-crystal X-ray analysis. The structure of complex 1 illustrates that aurophilicity and hydrogen bonding interactions increase dimensionality, generating a 2-D interdigitating system. The spectroscopic and magnetic properties have been investigated. 相似文献
977.
Yan Shiping Wang Genglin 《高等学校化学研究》1991,(1)
The title compound C18 H25 NC4ClBr2Cu crystallizes in space group P 1 with a = 1.0105(2)nm b=1.0821(1) nm, c=1. 1007(2) nm, a=80. 00(1)°,β=80. 26(1)° γ=77. 83(1)°. Z=2, D = 1. 831 g/cm3, μ=62. 658 cm-1(Mok(?)). The final refinement converged to R=0. 031 for 2547 independent observed reflections. The complex molecule consists of two cationic moieties (HL)+ and an anion which appears as a bromide-bridged copper dimer (Cu2Br6)2-. This structural characterization seems to be rare in metal complexes with crown-ether. 相似文献
978.
Di Zao Li Yan Li Xiao Guang Chen Chen Gen Zhu Jing Yang Hong Yan Liu Xian Dao Pan 《中国化学快报》2007,18(11):1335-1338
A series of heterocyclic acid esters of camptothecins as new compounds had been synthesized by acylation method,their in vitro and in vivo antitumor activities were evaluated.The cytotoxic results showed that 6 possessed the best efficacy on six human cancer cell lines in the six classes of CPTs' derivatives.In vivo testing results indicated that 9 had better antitumor activity against mouse liver carcinoma H_(22) than topotecan. 相似文献
979.
Dong R Yan X Pang X Liu S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(3):557-561
Raman spectra of collagen and DNA were discussed at different temperatures. The temperature-dependence of Raman intensity was obtained in the region from -150 to 200 degrees C. Four denaturation points at 0, 40, 68 and 90 degrees C of collagen and two peaks at 38 and 82 degrees C for DNA were obtained. The wavenumbers of many vibrational modes were found to increase for lower temperature, but the peak at 1302 cm(-1) of collagen and the peak at 1101 cm(-1) of DNA showed the opposite trend. In all of the vibrational modes of DNA, the bases showed the most sensitive to different temperatures and there is a pronounced shift of bands at 70 degrees C, the starting point of denaturation. 相似文献
980.
A facile construction of the typical framework of narcissus alkaloids has been realized by virtue of the development of a practical route involving stereocontrolled epoxide formation and SnCl(4)-catalyzed arene-epoxide coupling. To achieve this goal, it proved to be necessary to devise a strategy that would enable chemical transformations to install an epoxy moiety in a congested environment. The successful preparation of a hindered epoxide from O-isopropylidene-protected 4-aminocyclohexenol required three steps consisting principally of controlled bromohydration and base-promoted closure and N-alkylation. It was found that a catalytic amount of SnCl(4) not only maintained the catalytic cycle but also effected clean arylation to form a fused BC ring system. Several tactics that ultimately proved to be unsatisfactory are also discussed in an effort to set important boundary limits on arene-epoxide coupling. The requisite enantiopure 4-aminocyclohexenol was available via an asymmetric cycloaddition of diene to camphor-based chloronitroso. The total synthesis of (+)-narciclasine was realized in nine steps with an overall yield of 19%. 相似文献