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111.
The Cu/SiO2 catalyst prepared by incipient wetness method exhibited very high activity and selectivity for the vapor-phase synthesis of JV-butylaniline from aniline and 1-butanol. When Cu loading was 0.70 mmol/g-SiO2 and the catalyst precursor was calcined at 500 ℃, 1-butanol conversion reached 99%, and the selectivity of JV-butylaniline exceeded 97%. 相似文献
112.
Sulfated porous carbon (PC-SO3H) catalyst was successfully synthesized from one-pot treatment of porous polydivinylbenzene in H2SO4 at 250 C, which exhibited very good catalytic performances in the production of 5-hydroxymethylfurfural from fructose. 相似文献
113.
114.
3-胺基取代苯并吡喃酮类化合物的设计合成及抗肿瘤活性 总被引:2,自引:0,他引:2
根据生物电子等排原理, 设计并合成了一系列新颖的3-胺基取代苯并吡喃酮类化合物. 通过1H NMR, 13C NMR, MS, IR及元素分析确定其结构. 抗肿瘤活性测试结果表明, 部分该系列化合物对人结肠癌细胞株HCT116和人肝癌细胞株7721具有较好的抑制活性, 其中化合物6c, 6f, 6i, 6m和6o对人肝癌细胞株7721的半数抑制浓度(IC50)值均小于对照品姜黄素(IC50=10.53 μmol8226;L-1), 化合物6f对人结肠癌细胞株HCT116和人肝癌细胞株7721的IC50值分别为5.57和4.92 μmol8226;L-1, 均小于姜黄素的相应值. 相似文献
115.
116.
We describe the first example of Rh-catalyzed intermolecular C-alkylation of cyclic 1,2-diketones using simple terminal olefins as alkylating agents. Aminopyridine is employed as a recyclable directing group. First, it reacts with ketones to give enamines and delivers Rh to activate the vinyl C-H bonds in the same pot; second, it can be cleaved off and recovered via hydrolysis. A broad range of olefins can be utilized as substrates, including aliphatic, aromatic olefins and vinyl esters. The efficiency of this method is also demonstrated in the synthesis of a natural flavoring compound, 3-ethyl-5-methyl-1,2-cyclopentadione (one-pot 53% yield vs a previous four-step route 16% yield from the same starting material). This work is expected to serve as a seminal study toward catalytic ketone α-alkylation with unactivated olefins. 相似文献
117.
Hailin Dong 《Journal of organometallic chemistry》2011,696(9):1803-7127
[ReBr2(NO)(CH3CN)(PTA)2] (PTA = 1, 3, 5-triaza-7-phosphaadamantane) catalyzes the alcoholysis of ammonia-borane and amine-boranes and the catalytic transfer hydrogenations of various terminal olefins. Excellent yields were achieved at 70 °C in isopropanol using tBuOK as a co-catalyst affording TOF values up to 396 h−1. 相似文献
118.
Several rare earth‐doped, calcium‐based magnetic catalysts were prepared for the synthesis of glycerol carbonate. The basicity and basic strength analysis of the catalysts showed that the doping of rare earth improved the basicity of the catalysts, and the doping of lanthanum maximized it. In addition, with the doping of lanthanum, the particle size of the catalyst became smaller to promote the organic reactants near the active sites of catalysts, thereby effectively improving the performance. NiFe2O4@[CaO‐La2O3] shows better catalytic performance with 99.0% yield of glycerol carbonate compared to the other catalysts. The NiFe2O4@(CaO‐La2O3) could be reused in six cycles without significant loss in activity. 相似文献
119.
Xiuming Wu Fengshou Dong Jun Xu Xingang Liu Xiaohu Wu Yongquan Zheng 《Journal of separation science》2020,43(11):2217-2227
Pydiflumetofen is registered in many countries and is widely used in crop production in the racemate form. However, the environmental behavior of the enantiomers has not been studied. An effective and sensitive chiral analytical method was first established for analyzing the pydiflumetofen enantiomers by supercritical fluid chromatography with tandem triple quadrupole mass spectrometry. The enantiomers could be separated and detected using the Chiralcel OD‐3 column in less than 3 min. The separation conditions were as follows: mobile phase, CO2/methanol (80:20); flow rate, 1.0 mL/min; column temperature, 30°C, auto back‐pressure regulator pressure, 2000 psi with modified quick, easy, cheap, effective, rugged, and safe sample treatment method. The average recoveries of analytes from both matrices at three spiking levels were in the range of 84.1–103.0%. The limit of quantitation for each enantiomer was 0.005 mg/kg with a baseline resolution of approximately 1.64. The method was applied to monitor the enantioselective dissipation of pydiflumetofen in grape and soil. In grapes, (?)‐pydiflumetofen was degraded more rapidly than (+)‐pydiflumetofen. In soil, (+)‐pydiflumetofen was preferentially degraded. The data provided useful references for the risk assessment and rational use of pydiflumetofen in agriculture. 相似文献
120.
Dong Lu Xiao-Chun Yang Bing Leng Xiao-Di Yang Cong-Wu Ge Xue-Shun Jia Xi-Ke Gao 《中国化学快报》2016,27(7):1022-1026
A series of core-expanded naphthalene diimides (NDI-DTYM) and thiophene-based derivatives (1a-c) were designed and synthesized to investigate the relationship between molecular structures and the highest occupied molecular orbital (HOMO) energy levels but has little impact on the lowest unoccupied molecular orbital (LUMO) energy levels. The results demonstrated that increasing the number of thiophene units can gradually elevate the HOMO energy levels but had little impact on the LUMO energy levels. The n-channel organic field-effect transistors (OFETs) based on 1b and 1c have demonstrated that these almost unchanged LUMO energy levels are proper to transport electrons. 相似文献