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Pinacol Coupling Reactions Catalyzed by Active Zinc

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Chinese Chemical Letters 2005年第11期16卷 1459-1462页

作者： Hui ZHAO Wei DENG qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026

Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.

关键词： Pinacol coupling reaction active zinc carbonyl compounds electron transfer.

Products and production routes for the catalytic conversion of seed oil into fuel and chemicals: a comprehensive review

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Science China Chemistry 2015年第7期58卷 1110-1121页

作者： Mazloom Shah Jian-Jun Dai qing-xiang guo Yao Fu Anhui Province Key Laboratory of Biomass Clean Energy Department of Chemistry University of Science and Technology of China

With the depletion of fossil resources, there is a need to find alternative resources of fuels and chemicals. The use of renewable feedstock such as those from seed oil processing is one of the best available resources that have come to the fore-front recently. This paper critically analyzes and highlights major factors in the biodiesel industry, such as seeds oil composition, production methods, properties of biodiesel, problems and potential solutions of using vegetable seed oil, the composition, quality and effective utilization of crude glycerol, the catalytic conversion of glycerol into possible fuels and chemicals.

关键词： seed oil catalytic conversion biodiesel glycerol fuels and chemicals

Triphenylphosphine-catalyzed isomerization of alkynyl ketones in aqueous solution

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Chinese Chemical Letters 2007年第9期18卷 1029-1032页

作者： qing Fa Zhou Fei Yang qing xiang guo Song Xue Department of Chemistry University of Science and Technology of China Hefei 230026 China

An efficient isomerization of alkynyl ketones to (E,E)-diene ketones was developed. The reaction catalyzed by 20 mol% triphenylphosphine in aqueous media gave the desired products in good yields.

关键词： Triphenylphosphine Isomerization Alkynyl ketones Water

Novel fluorescent chemosensor for Ag^+ based on coumarin fluorophore

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Chinese Chemical Letters 2008年第8期19卷 977-980页

作者： Mao xiang Wang xiang Ming Meng Man Zhou Zhu qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026 China

A novel chemosensor 1 （CS1） bearing one coumarin and two carbodithioate groups was synthesized and its fluorescent sensing behavior toward metal ions was investigated. Ag^＋ addition to a CH3COCH3/H2O （3：7, v：v） solution of CS1 gave a significantly quenched fluorescence. Other ions including Pb^2＋, Zn^2＋, Cu^2＋, Ca^2＋, Cd^2＋, Co^2＋, Mg^2＋, Mn^2＋, Hg^2＋, Ag^＋, Ni^2＋ induced no or much smaller spectral changes. This constitutes an ON-OFF Ag^＋-selective fluorescent chemosensor.

关键词： Ag^+ chemosensor Fluorescence PET Coumarin

A novel selective fluorescent chemosensor for Cu(Ⅱ)

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Chinese Chemical Letters 2007年第11期18卷 1403-1406页

作者： Mao xiang Wang xiang Ming Meng Man Zhou Zhu qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026 China

A novel fluorescence enhancement Cu^2＋ chemosensor derived from coumarin was prepared. Emission study found that it exhibits evident Cu^2＋-arnplified fluorescence prior to Co^2＋, Pb^2＋, Mg^2＋, Mn^2＋, Ni^2＋, Zn^2＋, Fe^3＋, Ag^＋ and Cd^2＋, and the largest emission enhancement factor is about 9 at a ratio of 2：1 （chemosensor 1/Cu^2＋）.

关键词： Cu^2+ chemosensor Fluorescence 荧光性 Coumarin

1,3-Dicarbonyl compounds as phosphine-free ligands for Pd-catalyzed Heck and Suzuki reactions

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Chinese Chemical Letters 2007年第6期18卷 625-628页

作者： Xin Cui Juan Li Lei Liu qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026 China

Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reaction... 详细信息

关键词： Palladium catalyst Suzuki reaction Heck reaction Phosphine-free ligand

Design and Synthesis of Lipids Bearing Nucleosides as Gene Vectors

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Chinese Chemical Letters 2001年第9期12卷 779-782页

作者： Man Zhou ZHU Qi Hua WU qing xiang guo Department of Chemistry University of Science and Technology of ChinaHefei 230026

Some novel lipids bearing nucleosides were designed and synthesized as gene vectors, and the structures of these compounds were characterized by UV, IR, 1HNMR, 13CNMR and elemental analysis.

关键词： Gene vector lipid nucleoside synthesis

On the Structure of the Arginine-carboxylate Salt Bridge:A Density Functional Theory Study

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Chinese Chemical Letters 2001年第3期12卷 219-222页

作者： Ting Wei MU Yong FENG Lei LIU qing xiang guo Department of Chemistry University of Science and Technology of ChinaHefei 230026

High level density functional theory (DFT) calculations are performed for the first time to answer the question whether the arginine-carboxylate salt bridge stays in a zwitterionic state or a neutral one. The results indicate that in the gas phase, the neutral form is more stable and hence proton transfer occurs from guanidinium to carboxylate. However, in an aqueous solution the zwitterionic form should be favored. The difference might he caused by the electrostatic interaction between the salt bridge and its molecular environment. Therefore, the solvation effect has to be considered in the modeling of proteins, whose stabilization depends heavily on the salt-bridges.

关键词： Arginine-carboxylate interaction salt bridge DFT proton transfer solvation effect

Synthesis of α-Arylated Esters from Aryl Halides

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Chinese Chemical Letters 2006年第5期17卷 595-598页

作者： Wei DENG Ye Feng WANG Lei LIU qing xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026

An operationally simple and inexpensive catalyst system was developed for the cross coupling of aryl iodides and bromides with ethyl acetoacetate by using CuI as catalyst and Nmethyl glycine as ligand. The reaction represents a novel Cu-catalyzed C-C cross coupling reaction. This procedure is applicable to the preparation of pharmaceutically important α- arylalkanoic acids.

关键词： Cross coupling reaction CuI ethyl acetoacetate aryl halide α-arylalkanoic acids.