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Crystal Structure Theory and Applications 2020年第3期9卷 49-62页

作者： Avantika Hasija V. Prakash M. Shet Prakash Vasu G. Krishnasamy Deepak Chopra Crystallography and Crystal Chemistry Laboratory Department of Chemistry Indian Institute of Science Education and Research Bhopal Bhopal Madhya Pradesh India Sri Sairam College of Engineering Karnataka India Department of Studies and Research in Chemistry University College of Science Tumkur University Tumakuru Karnataka India Vivekananda Degree College Malleshwaram Karnataka India Department of Studies and Research in Organic Chemistry Tumkur University Tumakuru Karnataka India

In the current study, two novel knoevenagel condensation products of substituted napthofuran-2-carbaldehydes were designed, synthesized and characterized. In order to study the intermolecular interactions of title compounds, single crystals were grown by slow evaporation solution growth technique at room temperature and crystal structure has been determined by single crystal X-ray diffraction technique. Both the molecules crystallize in the monoclinic centrosymmetric space group P21/c with one molecule in the asymmetric unit. In compound [4] the molecules are connected via bifurcated C-H···O=C and C-H···N=C H-bonds and van der Waals interactions forming a layered structure, whereas in compound [5a] the molecular conformation is stabilized via intramolecular C-H···O H-bond and molecule interacts with other molecule generated via 21-screw via bifurcated C-H···O=C alo

关键词： Napthofuran-2-Carbaldehyde 8-Nitro Napthafura-2-Carbaldehyde knoevenagel condensation Single Crystal and Hirshfeld Surface Analysis

Amides as surrogates of aldehydes for C–C bond formation:amide-based direct knoevenagel-type condensation reaction and related reactions

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Science China Chemistry 2020年第1期63卷 11-15页

作者： Wei Ou Pei-Qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical Biology College of Chemistry and Chemical Engineering Xiamen University

Aldehydes are perhaps the most versatile compounds that enable many C-C bond forming reactions,which are not amenable for other subclasses of carbonyl *** report the first use of amides as surrogates of aldehydes for C-C bond formation,namely,the direct knoevenagel-type condensation based on *** one-pot method consists of controlled reduction of an amide with LDBIPA[LiAlH(iBu)2(OiPr)],Lewis acid-mediated release of a reactive iminium ion intermediate,nucleophilic addition,and in situ elimination of *** reaction shows good functional group *** also demonstrated that the Schwartz reagent could be used as an alternative of *** employment of nitromethane and a silyl enol ether as the nucleophiles opens an avenue for the unprecedented amide-based nitro-aldol condensation reaction and aldol condensation reaction,respectively.

关键词： amides knoevenagel condensation C–C bond formation one-pot reaction amide transformation

Negative charged Lindqvist hexatantalate efficiently catalyzed knoevenagel condensation

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Negative charged Lindqvist hexatantalate efficiently catalyz...

Solvent-free knoevenagel condensations over TiO2

河南省化学会2018年学术年会

作者： Qiaofei Xu Pengtao Ma Jingping Wang Jingyang Niu Henan Key Laboratory of Polyoxometalate Chemistry Institute of Molecule and Crystal EngineeringCollege of Chemistry and Chemical EngineeringHenan University

The good coincidence between experiment and theory revealed that negative charged Lindqvist hexatantalate K Ta O(Ta) as a strong base has exhibited superior catalysis for the knoevenagel condensation of various carbonyl compounds with active methylene compounds. Moreover, the high basicity of negative oxygen in Ta have been proved by Density functional theory(DFT) calculation, which is a much more negative value than those of other polyoxometalates. Experimental study suggests that the lacunary POTs are more active than the plenary ones but Lindqvist Ta is the best one which can efficiently catalyze neglecting the steric and electronic effect of aromatic aldehydes under mild conditions. Meanwhile, a proper mechanism according to the DFT speculates that the most negative charged terminal oxygens in Ta would be pivotal in this transformation.

关键词： Hexatantalate knoevenagel condensation Catalysis

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Chinese Journal of Chemistry 2007年第10期25卷 1563-1567页

作者： HOSSEINI-SARVARI, Mona SHARGHI, Hashem ETEMAD, Samane Department of Chemistry Faculty of Science Shiraz University Shiraz 71454 Iran

A study involving the scope of substrates in the knoevenagel reaction under SFC has been conducted. Reactivity trends favored formation of the condensation product using both electron deficient and rich aryl aldehydes. A recycling study confirmed that the reaction medium could be used multiple times affording, with each run, the desired condensation product in excess of 95% conversion.

关键词： titanium dioxide aldehyde malononitrile knoevenagel condensation solvent-free

A Green and Highly Efficient Protocol for Catalyst-free Kno- evenagel condensation and Michael Addition of Aromatic Al- dehydes with 1,3-Cyclic Diketones in PEG-400

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Chinese Journal of Chemistry 2011年第11期29卷 2407-2410页

作者： Firouzeh, Nemati Hossein, Kiani Department of Chemistry Faculty of Science Semnan University Semnan Iran

A convenient, highly efficient and green approach for synthesis of tetraketones from aromatic aldehydes with dimedone and 1,3-indanedione at room temperature in PEG-400 is described. The use of PEG-400 as the reaction medium and avoiding the use of any catalyst makes the process environmentally benign. Seven new compounds are reported.

关键词： Michael addition green chemistry polyethelene glycol knoevenagel condensation dimedone,1,3-Indanedione

Oleylamine-catalyzed Tandem knoevenagel/Michael Addition of 1,3-Cyclohexanediones with Aromatic Aldehydes

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Chemical Research in Chinese Universities 2018年第2期34卷 186-190页

作者： HE Xinwei WU Yuhao FAN Chenli LU Peng ZUO Youpeng SHANG Yongjia Key Laboratory of Functional Molecular Solids Ministry of Education Anhui Laboratory of Molecule-based Materials(State Key Laboratory Cultivation Base) College of Chemistry and Materials Science Anhui Normal University Wuhu 241000 R R. China Department of Material Engineering Wuhu Institute of Technology Wuhu 241003 P. R. China

A convenient and efficient method was developed for the synthesis of 2,2＇-（arylmethylene）bis（3-hydrox- ycyclohex-2-enone） derivatives via the oleylamine-catalyzed tandem knoevenagel/Michael addition reactions of aromatic aldehydes and cyclohexane-1,3-diones. This transformation proceeded without any metal catalyst in non-toxic solvent at room temperature with high isolated yields. A plausible mechanism for this process was pro- posed.

关键词： 2,2'-(Arylmethylene)bis(3-hydroxycyclohex-2-enone) knoevenagel condensation Michael addition Oleylamine Tandem reaction

Tri-amines polyacrylonitrile fiber efficiently mediated knoevenagel condensations in water

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Tri-amines polyacrylonitrile fiber efficiently mediated Knoe...

A Convenient Heterogeneous Reduction of knoevenagel Product by Hantzsch Ester and Its Development into Reductive Alkylation of Malononitrile

河南省化学会2016年学术年会

作者： Xian-Lei Shi Feng Wang Peigao Duan Qianqian Hu Department of Applied Chemistry College of Chemistry and Chemical Engineering Henan Polytechnic University

A novel and efficient fiber catalyst for knoevenagel condensation has been prepared by aminating the commercially available polyacrylonitrile fiber with N,N-dimethyl-1,3-propanediamine and triethylene tetramine sequently. The detailed characterization by elemental analysis, Fourier transform infrared spectroscopy(FTIR), and scanning electron microscopy(SEM) confirmed the changes and stability of the fiber catalyst during the modification and utilization processes. The mediated knoevenagel condensations proceeded smoothly in the presence of the fiber catalyst and the products were obtained in good to excellent yields(92-99%). Moreover, the reaction can be easily carried out in different solvents of varying polarities, and even with water as the solvent could also achieve a nearly quantitative yield at room temperature. The newly developed fiber catalyst was also found to exhibit excellent recyclability(up to 10 times) and, the procedure is operationally simple and amenable to the gram scale in continuous-flow processing.

关键词： fiber catalyst supported catalysis knoevenagel condensation recyclability

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Chinese Journal of Chemistry 2014年第7期32卷 650-653页

作者： Yong-Qing Yang Zheng Lu School of Pharmacy Jiangsu UniversityZhenjiangJiangsu 212013China

Poor solubility of Hantzsch ester is used as indicator in the reduction of methylidene *** knoevenagel reaction is integrated to develop a reductive alkylation of malononitrile with aryl and aliphatic aldehyde as the ... 详细信息

关键词： heterogeneous reduction Hantzsch ester knoevenagel condensation reductive alkylation

Primary amine-functionalized mesoporous phenolic resin as an effective and stable solid base catalyst for knoevenagel reactions in water

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Green Synthesis and Catalysis 2020年第1期1卷 79-82页

作者： Kaixuan Wang Huating Jiang Min Tong Yao Xiao Hexing Li Fang Zhang School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai 200237China The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials Shanghai Normal UniversityShanghai 200234China

A primary amine functionalized ordered mesoporous phenolic resin(NH2-MPR)was obtained by an evaporationinduced self-assembly *** as-prepared NH2-MPR material possessed large surface area and ordered twodimensional hexagonal mesoporous ***,the amine groups were well-dispersed in the mesoporous *** can act as an efficient solid base to promote knoevenagel condensation of various aldehydes with ethyl cyanoacetate in water with high conversion and *** excellent performance was attributed ordered mesopores and hydrophobic pore surface,which resulted in the decreased the interference of water solvent and the increased active sites *** that it was comparable with homogenous base catalysts in the water-medium knoevenagel condensation reaction,and it can be reused for at least five times without significant reduction in the catalytic efficiency.

关键词： Primary amines Functionalized ordered mesoporous resin Solid base knoevenagel condensation Water solvent

Mesoporogen-free synthesis of hierarchical sodalite as a solid base catalyst from sub-molten salt-activated aluminosilicate

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Particuology 2020年第1期18卷 48-54页

作者： Jinbiao Yang Tiesen Li Xiaojun Bao Yuanyuan Yue Haiyan Liu State Key Laboratory of Heavy Oil Processing China University of Petroleum18 Fuxue RoadBeijing 102249China East-China Design Branch China Petroleum Engineering&Construction Corporation2 Huayan RoadQingdao 266071China National Engineering Research Center of Chemical Fertilizer College of Chemical EngineeringFuzhou University2 Xueyuan RoadFuzhou 350116China

A rapid and environmentally friendly approach to synthesize hierarchical sodalite from natural aluminosilicate mineral without the involvement of any mesoporogen or post-synthesis treatment was *** strategy involves three important steps:the first is the depolymerization of an aluminosilicate mineral into highly reactive silicon and aluminum species with ideal meso-scale structures through activation of a sub-molten *** second step is the hydrolysis and condensation of the activated aluminosilicate mineral into zeolitic precursors that also have a meso-scale *** third is the rapid zeolitization of the zeolitic precursors through the reversed crystal growth route at room temperature and ambient pressure to form hierarchical *** physicochemical properties of the as-synthesized sodalite were systematically characterized,and the formation mechanism of the hierarchical pore structure was *** used as a solid base catalyst for knoevenagel condensation,the as-synthesized sodalite and its potassium ion-exchanged product with hierarchical micro-meso-macroporous structure both exhibited high catalytic activity and product selectivity.

关键词： Natural aluminosilicate mineral Hierarchical sodalite Reversed crystal growth route Kirkendall effect Solid base catalyst knoevenagel condensation