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Preparation and Characterization of Acylated Chitosan

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Chemical Research in Chinese Universities 2005年第1期21卷 114-116页

作者： LIMing-ehun LIUChao XINMei-hua ZHAOHuang WANGMin FENGZhen SUNXiao-li CollegeofMaterialScienceandEngineering HuaqiaoUniversityQuanzhou362011P.R.China

Fully acylated chitosan and N, N-diacyl chitosan were prepared. The products were characterized by elemental analysis, FTIR and 1H NMR. The experimental results indicate that the average degree of acylation depends on the volume ratio of pyridine to chloroform in the reaction medium, the chain length of the acylation agent used, and the molecular weight of chitosan raw materials. The XRD measurements were carried out for pure chitosan, fully acylated chitosan and N, N-diacyl chitosan to verify the crystallinity change caused by the acylation.

关键词： Chitosan acylation Degree of substitution XRD

Recent advances towards electrochemical transformations ofα-keto acids

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Chinese Chemical Letters 2021年第9期32卷 2729-2735页

作者： Jingjing Li Sheng Zhang Kun Xu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China Faculty of Environment and Life Beijing University of TechnologyBeijing 100024China College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China

As a kind of environmentally benign reagents,α-keto acids have been extensively employed as key starting materials in organic *** electrosynthesis has the advantages of reducing byproduct generation,improving the cost-efficiency of synthetic processes,and accessing reactive intermediates under mild *** by the merits of organic electrosynthesis,α-keto acids have shown many synthetic applications in electrochemical acylation,cyclization,and reductive amination reactions with improved efficiencies and *** review covers the recent breakthroughs achieved in the electrochemical transformations ofα-keto acids,aimed at highlighting these electrochemical reactions’features and mechanistic ***,the practicalities and limitations of these transformations are also presented where possible.

关键词： Electrosynthesis Electrooxidation acylation α-Keto acids Decarboxylation

Converting Thiophene in Simulated Coking Crude Benzene to N,N-Dimethyl-2-thiophenecarboxamide by Dimethylcarbamyl Chloride Under Mild Conditions

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Chemical Research in Chinese Universities 2019年第4期35卷 674-679页

作者： SHEN Xizhou SONG Hao FANG Liuya DENG Hang GAN Feng SHEN Zhi School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Wuhan 430205 P. R. China Key Laboratory for Green Chemical Process Ministry of Education Wuhan Institute of Technology Wuhan 430073 P. R. China

Since the content of thiophene in coking crude benzene is high, it is necessary to remove it from coking crude benzene for efficient utilization. In this study, an important intermediate, N,N-dimethyl-2-thiophenecarboxamide, was synthesized from thiophene and dimethylcarbamyl chloride. The influences of the dosages of dimethylcarbamyl chloride and ZnCl2 catalyst, reaction temperature and time on the removal rate were further explored based on the reaction *** structure of the target product was characterized by means of MS,NMR and 13C *** removal rate of thiophene was 98.14% after the reaction for 2 h and thiophene was almost removed after the reaction for 3 h under the optimal reaction conditions [a molar ratio of n(thiophene):n(dimethylcarbamyl chioride):w(ZnCl2)=1:12:10,300 r/min, 318 K and 101.325 kPa].The acylation of thiophene with dimethylcarbamyl chloride was approximately in accord with the first order kinetic equation at *** activation energy was 53.9850 kJ/mol and the pre-exponential factor was 1.4521×10^9 h^-1.

关键词： Coking crude benzene F-C acylation Acyl chloride Thiophene Thiophene derivative

Investigation on the Coordination Mode of IL-Supported Diols Used as Phosphine-Free Ligands for Palladium Catalyzed Heck Reaction

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Chinese Journal of Chemistry 2013年第10期31卷 1250-1256页

作者： Yueqin Cai Gonghua Song Xiao Chen School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China Shanghai Key Laboratory of Chemical Biology Institute of Pesticides & Pharmaceuticals East China University of Science and Technology Shanghai 200237 China

The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well.

关键词： homogeneous catalysis acylation Heck reaction phosphine-free ligands

Aqueous-Phase, Palladium-Catalyzed Heck Reaction： The Significant Role of CN-containing Counter Anion

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Chinese Journal of Chemistry 2012年第12期30卷 2819-2822页

作者： Cai Yueqin Song Gonghua Zhou Xiaoying School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China Shanghai Key Laboratory of Chemical Biology Institute of Pesticides & Pharmaceuticals East China University of Science and Technology Shanghai 200237 China

Water-soluble diol-functionalized imidazolium ionic liquid 1, prepared from 2,2-bis（1-methyl-methyl-imida- zolium）propane-l,3-diol bromide, potassium hydroxide, and malononitrile, was used as an efficient phosphine-free ligand for palladium-catalyzed arylation of aryl halides with acrylates in aqueous phase under mild conditions. It was found that the synergistic coordinating action of diol-functionalized imidazolium cation with CN-containing anion played the key role in improving the activity and stability of the catalyst.

关键词： homogeneous catalysis acylation Heck reaction phosphine-free ligand nitrile group

An Efficient Enantioselective Synthesis of Blastmycinone

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Chinese Journal of Chemistry 2005年第11期23卷 1519-1522页

作者： YANG, Yong-Qing wu, Yi-Kang State Key Laboratory of Bio-organic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Blastmycinone, a degradation product of the antibiotic antimycin A, was synthesized with a TiCl4-mediated asymmetric aldolization as the key step. Some unexpected yet interesting chemistry was also observed.

关键词： lactone asymmetric synthesis aldol acylation chiral auxiliary

Synthesis and Conformation of New Azo-functionalized Calix[4]arenes

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Chinese Journal of Chemistry 2006年第9期24卷 1209-1213页

作者：邢彦军王艳佳 College of Chemistry and Chemical Engineering Donghua University Shanghai 200051 China

A new family of functionalized calix[4]arenes has been synthesized from calix[4]arene or azo-calix[4]arene by acylation with the corresponding co-alkylmercapto acid chloride. Six new compounds 4a-4e and 5a-5e were isolated and characterised by MALDI, elemental analyses, IH NMR and 13C NMR. NMR spectral data showed that these azo-functionalized calix[4]arenes 5a-5c are all in 1,3-alternate conformation in solution at room temperature while calix[4]arenes 4a-4e are all in cone conformation. The IR and UV properties of calix[4]arenes 5n-5e were also investigated.

关键词： calixarene azo-functionalized 1,3-alternate acylation

Synthesis of Chiral 3-Acylcamphors

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Chinese Chemical Letters 1999年第5期10卷 347-348页

作者： Zheng Ning LI Zhi Xiu XU Zhuo ZHENG Hut Lin CHEN(Dalian Institute of Chemical Physics, the Chinese Academy of Sciences, Dalian 116023) Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

3-Acylcamphors were synthesized in moderate yields by the condensation of camphor with esters using sodium hydride as a base.

关键词： camphor acylation 3-acylcamphor synthesis

Convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides from (E)-4-(2-bromovinyl)phenyl acetate

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Chinese Chemical Letters 2009年第5期20卷 545-548页

作者： Yu Bo Jiang Chun Xiang Kuang Department of Chemistry Tongji University Siping Road 1239 Shanghai 200092 China

A convenient one-pot synthesis of functionalized （E）-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide （DCC） and dimethylamino-pyridine ... 详细信息

关键词： One-pot synthesis (E)-2-Arylvinyl bromide acylation Deacetylation