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L-Prolinamide Catalyzed Aqueous Direct aldol reaction： an Environment-friendly Method for the Synthesis of β- Hydroxyl keto nes

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Chinese Journal of Chemistry 2007年第7期25卷 962-967页

作者：彭以元刘汉崔明程津培 Key Laboratory of Green Chemistry Jiangxi Province and Department of Chemistry Jiangxi Normal University Nanchang Jiangxi 330027 China Department of Chemistry and State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China Key Laboratory of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang Jiangxi 330027 China

An environment-friendly L-prolinamide catalyzed aldol reaction has been developed. The reaction exhibited broad substrate generality, and high yields with good diastereoselectivity were obtained for cyclic *** simplicity of product isolation, usage of water as environmentally benign reaction medium, and the usage of cheap, readily available and recyclable catalyst make this process promising to be developed for large-scale preparation of β-hydroxyl ketones.

关键词： aldol reaction L-prolinamide β-hydroxylketone green chemistry

Asymmetric aldol reaction Catalyzed by Modularly Designed Organocatalysts

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Chinese Journal of Chemistry 2012年第11期30卷 2624-2630页

作者： Sinha, Debarshi Mandal, Tanmay Gogoi, Sanjib Goldman, Joshua J. 赵从贵 Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio Texas 78249-0698 USA

The self-assembly of the precatalyst modules, which are amino acids and cinchona alkaloid derivatives, leads to the direct formation of the desired organocatalysts without any synthesis. These modularly designed organocatalysts （MDOs） may be used for catalyzed asymmetric aldol reaction the corresponding aldol products may be obtained in mediocre diastereoselectivities （up to 79 ： 21 dr）. Depending on structure of the aldehyde substrates, to excellent ee values （up to 92% ee） with moderate

关键词： modularly designed organocatalysts aldol reaction asymmetric catalysis amino acid cinchona alka-loid thiourea

Direct Asymmetric aldol reaction Co-catalyzed by Amphiphilic Prolinamide Phenol and Lewis Acidic Metal on Water

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Chinese Journal of Chemistry 2013年第2期31卷 247-255页

作者： Tao Zhang Yunxiao Zhang Zaichun Li Zhongtai Song Hao Liu Jingchao Tao College of Chemistry and Molecular Engineering Zhengzhou University 75 Daxue Road Zhengzhou Henan 450052 China

An approach based on combinations of various water compatible Lewis acids and lipophilic group containing amphiphilic prolinamide co-catalysts has been evaluated for the direct asymmetric aldol reaction. From the broad screening of chloride salts from alkali metal to transition metal, LiC1, ZnCI2 and SnCI2 lead to the highest stereoselectivities. The optimized catalytic conditions （10 mol% prolinamide with 10 mol% MC12 or 20 mol% LiC1 at room temperature on water） gave anti-products with improved enantioselectivities （up to 99% ee） compared to the moderately stereoselective procedure based on prolinamide activation only.

关键词： aldol reaction amphiphilic prolinamide Lewis acidic metal Co-cayalyst asymmetric catalysis

Proline-based Amino Pyridine Dipeptides as Efficient Organocatalysts for Direct aldol reaction

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Chemical Research in Chinese Universities 2010年第1期26卷 50-54页

作者： GAO Jun-long ZHENG Liang-yu ZHANG Suo-qin ZHANG Xin-min SUN Guo-dong QIN Lin LI Yao-xian LIU Qing-wen LI Xiao-bo College of Chemistry Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130021 P. R. China

A series of proline-based amino pyridine dipeptide organocatalysts was synthesized and applied in direct asymmetric intermolecular aldol reaction. These catalysts showed good solubility in organic solvents, good yields （73%--97%） and enantioselectivitives（74%--94%）. Among them, dipeptide organocatalyst（2） was found to be the most efficient one for the asymmetric aldol reaction between cyclohexanone and 4-nitrobeznaldehyde. After optimizing the catalytic reaction conditions, we found that the catalyst showed high yield（97%）, enantioselectivity（e.e., up to 92%） and anti-diastcreoselectivity（up to 95：5） at mild room temperature without any additives.

关键词： Proline-based dipeptide aldol reaction Enantioselectivity

A high-performance potassium-ion capacitor based on a porous carbon cathode originated from the aldol reaction product

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Chinese Chemical Letters 2020年第9期31卷 2215-2218页

作者： Xu Yu Mingjie Shao Xuemei Yang Chongxing Li Tong Li Danyu Li Rutao Wang Longwei Yin Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationSchool of Materials Science and EngineeringShandong UniversityJi'nan 250061China Suzhou Institute of Shandong University Suzhou 215123China

Potassium-ion capacitors(KICs) emerge as a promising substitute for the well-developed lithium-ion capacitors(LICs),however,the energy density of KICs is below expectations because of lacking a suitable electrical double-layer positive *** chemical activation of the aldol reaction product of acetone with KOH,we synthesized a porous ca rbon with a Brunauer-Emmett-Teller surface area of up to 2947 m2/g and a narrow pore size distribution ranging from 1 nm to 3 ***-cell(versus potassium metal) test demonstrates that this porous carbon has high capacitive performance in K+ based organic ***,a novel KIC fabricated by this porous carbon as the cathode,yields high values of energy density and power *** processes used to make this porous carbon are readily low-cost to fabricate metal-ion capacitors.

关键词： Porous carbon Chemical activation N,P co-doped carbon aldol reaction Potassium-ion capacitor

Facile aldol reaction Between Unmodified Aldehydes and Ketones in Bronsted Acid Ionic Liquids

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Chemical Research in Chinese Universities 2007年第5期23卷 549-553页

作者： LIU Bao-you ZHAO Di-shun XU Dan-qian XU Zhen-yuan Key Laboratory of Contaminant Controlling in Biology of Hebei Province College of Environmental Science and Engineering Hebei University of Science and Technology Shijiazhuang 050018 P. R. China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of Technology Hangzhou 310014 P. R. China Pharmaceutical Engineering Research Centre of Hebei Province College of Chemical and Pharnmceutical Engineering Hebei University of Science and Technology Shijiazhuang 050018 P. R. China

A series of condensation reactions of unmodified ketones and aromatic aldehydes to prepare α,β-unsaturated carbonyl compounds by means of aldol reactions in Bronsted acid ionic liquids（BAILs）was explored.1-Butyl-3-methylimidazolium hydrogen sulphate（BMImHSO4）acting as an effective media and catalyst in aldol reactions was compared with other BAILs,with the advantages of high conversion and *** product was easily isolated and the left ionic liquid can be readily recovered and reused at least 3 times with almost the same *** scope and limitation of the present method were explored and the possible catalytic mechanism was speculated.

关键词： Bronsted acid ionic liquid(BAIL) aldol reaction α,β-Unsaturated carbonyl compound

Enzymatic Promiscuity： Escherichia coli BioH Esterase-catalysed aldol reaction and Knoevenagel reaction

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Chemical Research in Chinese Universities 2014年第2期30卷 289-292页

作者： JIANG Ling YU Hongwei Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310007 P.R.China

Esterase BioH,which is obligatory for biotin synthesis in Escherichia coli,was found to exhibit a promiscuous ability to catalyse aldol and Knoevenagel reactions with moderate to good *** reaction conditions including organic solvent,molar ratio of ketone to aldehyde,enzyme amount,and reaction time were investigated to evaluate the effect of different reaction conditions on *** compounds were afforded in the best yield of 91.2％ for aldol reaction and 54.7％ for Knoevenagel *** addition,because the enzyme could be prepared with a low cost,this protocol could provide an economic route to conduct aldol and Knoevenagel reactions,which expand the field of enzymatic promiscuity.

关键词： Escherichia coli BioH esterase Catalytic promiscuity aldol reaction Knoevenagel reaction

Biocatalytic direct asymmetric aldol reaction using proteinase from Aspergillus melleus

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Science China Chemistry 2013年第7期56卷 939-944页

作者： YUAN Yi GUAN Zhi HE YanHong School of Chemistry and Chemical Engineering Southwest University

The direct asymmetric aldol reaction of aromatic aldehydes with cyclic or acyclic ketones was catalyzed by proteinase from Aspergillus melleus (AMP) in acetonitrile in the presence of water. A wide range of substrates could be transformed into the corresponding aldol products in yields up to 89%, enantioselectivities up to 91% ee and diastereoselectivities up to >99:1 (anti/syn). This work provided an example of enzyme catalytic promiscuity that widens the applicability of this biocatalyst in organic synthesis without the need for additional cofactors or special equipment.

关键词： enzyme catalysis aldol reaction proteinase promiscuity asymmetric synthesis

A Simple Primary Amine Derived from Cyclohexanediamine Catalyst for Asymmetric Direct aldol reaction

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A Simple Primary Amine Derived from Cyclohexanediamine Catal...