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knoevenagel condensation catalysed by poly(vinyl chloride) supported tetraethylenepentamine (PVC-TEPA)

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Chinese Chemical Letters 2007年第3期18卷 266-268页

作者： Fen Dong Yi Qun Li Rong Feng Dai Department of Chemistry Jinan University Guangzhou 510632 China

Poly（vinyl chloride） supported tetraethylenepentamine （PVC-TEPA） has been found to be an efficient catalyst for the knoevenagel condensation. A wide range of aromatic aldehydes easily undergo condensations with ethyl cyanoacetate and malononitrile in the commercial 95% ethanol in refluxing using PVC-TEPA as catalyst to afford the desired products of good purity in moderate to excellent yields. A recycling study confirmed that the catalyst could be reused, the yield of the desired condensation product were not reduced. The merits of this protocol are environmentally benign, simple operation, convenient work-up and good yields. Furthermore, the catalyst can easily be recovered and reused at five times with comparable yields.

关键词： knoevenagel condensation PVC-supported tetraethylenepentamine Catalysis

knoevenagel condensation of Acetylacetone with AldehydesCatalyzed by a New Catalyst Indium Trichloride

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Chinese Chemical Letters 1998年第2期9卷 123-124页

作者： Wang, L Zhang, YM Hangzhou Univ Dept Chem Hangzhou 310028 Peoples R China

The knoevenagel condensation of acetylacetone with aldehydes catalyzed by indium trichloride was carried out at room temperature in acetonitrile to give aryl- or alkylideneacetylacetones in moderate to good yields.

关键词： knoevenagel condensation indium trichloride acetylacetone aldehyde

knoevenagel condensation of α,β-unsaturated aromatic aldehydes with barbituric acid under non-catalytic and solvent-free conditions

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Chinese Chemical Letters 2007年第12期18卷 1431-1435页

作者： Cherkupally Sanjeeva Reddy Adki Nagaraj Department of Chemistry Kakatiya UniversityWarangal 506009India

An efficient route for the synthesis of 5-（arylpropenylidine）-2,4,6-pyrimidinetrione 3 from an appropriate α,βunsaturated aromatic aldehydes 1 and barbituric acid 2 under both non-catalytic and solvent-free microwave irradiation conditions was described. In this way, a range of biologically important compounds 3 was obtained in good to excellent yields （86-98%） in a very short reaction time （30-80 s）.

关键词： Barbituric acid knoevenagel condensation 5-(Arylpropenylidine)-2,4,6-pyrimidinetrione

Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient knoevenagel condensation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 75-84页

作者： Wen Xiao Peng Dong Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China Sinochem Quanzhou Energy Technology Co. Ltd.Quanzhou 362000China

Zeolite catalysts have found extensive applications in the synthesis of various fine ***,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic ***,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the knoevenagel condensation reaction for producing the useful fine chemical *** synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or *** characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX *** mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized *** synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing.

关键词： Hierarchical NaX zeolite Template-free synthesis Natural kaolinite knoevenagel condensation

A new 28-Ni-added poly(polyoxometalate)with B atoms:synthesis,structure and catalysis for knoevenagel condensation

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Science China Chemistry 2023年第5期66卷 1394-1399页

作者： Chen Lian Hai-Lou Li Guo-Yu Yang Key Laboratory of Cluster Science of Ministry of Educaiton School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing102488China

The synergistic effect of trivacant B-α-Ge W_(9)O_(34)fragments as structure-directing agents and inorganic B-O segments as intramolecular decoration afforded an unprecedented 28-Ni-added huge cluster K_(2)Na_(14)H_(10)[{Ni_(6)(OH)_(3)(H_(2)O)_(6)(Ge W_(9)O_(34))}{Ni_(8)-(μ_(6)-O)(OH)_(3)(H_(2)O)(BO(OH)_(2))(B_(2)O_(3)(OH)_(2))(Ge W_(9)O_(34))_(2)}]_(2)·46H_(2)O(1)under hydrothermal *** polyoxoanion of 1contains two half-units,[{Ni_(6)(OH)_(3)(H_(2)O)_(6)(Ge W_(9)O_(34))}{Ni_(8)(μ_(6)-O)(OH)_(3)(H_(2)O)(BO(OH)_(2))(B_(2)O_(3)(OH)_(2))(Ge W_(9)O_(34))_(2)}]^(13-),which joined together via Ni-O=W *** most fascinating feature is that each half-unit can be regarded as the fusion of an Ni_(6)(OH)_(3)(H_(2)O)_(6)(B-α-Ge W_(9)O_(34))({Ni_6Ge W_(9)})and a previously unobserved sandwiched Ni_(8)(μ_(6)-O)(OH)_(3)(H_(2)O)(BO(OH)_(2))(B_(2)O_(3)-(OH)_(2))(B-α-Ge W_(9)O_(34))_(2)({(Ni_(8)BB_(2))@(Ge W_(9))_(2)}),in which the{Ni_(8)BB_(2)}cluster contains a Lindqvist-type{Ni_(6)}core capped by two Ni O_(6)octahedra and further decorated by a BO(OH)_(2)({B})group and a binuclear B_(2)O_(3)(OH)_(2)({B_(2)})***,1 as a heterogeneous catalyst,has good catalytic activity for knoevenagel condensation under mild reaction conditions.

关键词： polyoxometalate hydrothermal synthesis high-nuclearity TMAPs knoevenagel condensation

Facile access to C-N bonds via unexpected side reactions of knoevenagel condensation and their application in high-efficiency organic solar cells

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Science China Chemistry 2024年第1期67卷 323-329页

作者： Daobin Yang Shuncheng Yang Hongqian Wang Lin Xie Pengyu Yan Ziyi Ge Zhejiang Engineering Research Center for Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The construction of C-N bonds is of great importance in the fields of biology,medicine,chemistry and materials ***,the replacement of organic base from pyridine to piperidine in the knoevenagel condensation process unexpectedly yields a series of novel organic molecules containing C-N ***,the synthesis method does not require any external transition-metals catalysis,and photo-/***,when the new compound 1b is added as a third component to a well-known binary system of PM6:Y6,the efficiency of the organic solar cell is significantly improved,resulting in an outstanding efficiency of 18.0%,which is one of the highest values reported to date for PM6:Y6-based ternary organic solar cells.

关键词： C-N bonds knoevenagel condensation cross-coupling reaction third component organic solar cells

Efficient knoevenagel condensation catalyzed by imidazole-based halogenfree deep eutectic solvent at room temperature

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Green Energy & Environment 2020年第2期5卷 124-129页

作者： Hao Qin Yishan Zhou Qian Zeng Hongye Cheng Lifang Chen Bingjian Zhang Zhiwen Qi Max Planck Partner Group at the State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China School of Chemical Engineering and Technology Sun Yat-Sen University135 Xingang West RoadGuangzhou510275China

For the first time,we employed the halogen-free deep eutectic solvent(DES)into the knoevenagel condensation between aromatic aldehydes and active methylene compounds at room *** DESs[3Im:PTSA]and[4Im:PTSA]were prepared by imidazole(Im)and p-tol-uenesulfonic acid(PTSA),which were experimentally screened from a series of organic acids with imidazole.a,b-Unsaturated carbonyl compounds were obtained in good to excellent yields under solvent-free conditions with fast reaction *** two DESs can be reused for multiple times with no loss of catalytic activity.

关键词： Halogen-free DES knoevenagel condensation Room temperature Recyclable catalyst Solvent-free condition

Basic Ionic Liquid: A Reusable Catalyst for knoevenagel condensation in Aqueous Media

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Chemical Research in Chinese Universities 2007年第2期23卷 169-172页

作者： GAO Guo-hua LU Liang ZOU Ting GAO Jin-bao LIU Ye HE Ming-yuan Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 P. R. China

An efficient, environmentally friendly procedure was developed for the condensation of aldehydes/ketones and activated methylene compounds with basic ionic liquid as the catalyst in water. This basic ionic liquid catalyst has a very high activity for knoevenagel condensation to give the corresponding products in 70%-97% isolated yields under mild conditions. The basic ionic liquid catalyst in aqueous system can be reused for six times without any significant loss of activity.

关键词： knoevenagel condensation Aqueous media Ionic liquid

Assembly and Post-modification of Fe3O4@MIL-100(Fe) for knoevenagel condensation

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Chemical Research in Chinese Universities 2018年第4期34卷 655-660页

作者： ZHANG Yanmei ZHANG Fan ZHANG Xiang XU Yingmei QI Xiaohui QUAN Chunshan Key Laboratory of Biotechnology and Bioresources Utilization Ministry of Education College of Life Science Dalian Minzu University Dalian 116600 P. R. China

Many efforts have been devoted to the integration of magnetic nanoparticles and metal organic frame- works, which makes it easy and simple to separate the nano-sized metal organic frameworks from liquid phase. Amino-functionalized magnetic metal organic frameworks[Fe3O4@MIL-100（Fe）-NH2] were prepared by a stepwise assembly method followed by post-modification with electron-rich reagent. This magnetic catalyst was characterized by means of X-ray diffraction（XRD）, transmission electron microscopy（TEM）, scanning electron micrnscopy（SEM） and nitrogen adsorption, and tested in knoevenagel condensation as a base catalyst. The magnetic catalyst exhibits a core-shell structure and can afford a high activity for the knoevenagel condensation due to its bifunctional property and reduced diffusion limitation. Furthermore, it could be recovered magnetically and recycled three times. Although activity loss was observed in the recycle experiments, it could be reactivated by dispersing in a fresh modifier solution.

关键词： Fe3O4 MIL-100(Fe) Heterogeneous catalyst knoevenagel condensation Magnetic separation