2017-89-2Relevant academic research and scientific papers
Imine-bridged periodic mesoporous organosilica as stable high-activity catalytic for Knoevenagel reaction in aqueous medium
Sun, Zechun,Wang, Yiran,Zhang, Zhiruo,Zhu, Fengxia,Zhao, Pusu,Li, Guisheng,Shao, Fengfeng,Rui, Jiahui
, p. 3107 - 3121 (2019)
An imine-functionalized mesoporous solid base catalyst (BA@BE-PMO) was prepared by template agent-directed self-assembly condensation of bis[3-(triethoxysilyl)propyl]amine and 1,2-bis(triethoxysilyl)ethane in acid solution. The imine groups with catalytic
Urea-functionalized mesoporous polymeric catalyst: A cooperative effect between support and secondary amine on water-medium Knoevenagel reactions
Zhu, Ruixing,Shen, Jian,Wei, Yongyi,Zhang, Fang
, p. 1861 - 1866 (2011)
Urea-functionalized mesoporous polymers (urea-MPs) were synthesized through the surfactant-directed urea-phenol-formaldehyde oligomers self-assembly approach. The as-prepared urea-MPs material exhibited superior catalytic activity than parent urea in water-medium Knoevenagel condensation reactions and could be used repetitively for seven times. The excellent activity could be attributed to the synergic effect derived from the secondary amine with the surface phenolic groups in the mesoporous support, which generated the acid-base cooperative catalytic behavior. Meanwhile, the urea functional groups embedded in the mesopore wall could inhibit the leaching of active species and thus resulted in the relatively good durability.
Basic polymerized imidazolide-based ionic liquid: An efficient catalyst for aqueous Knoevenagel condensation
Ding, Libing,Li, Hansheng,Zhang, Yaping,Zhang, Kun,Yuan, Hong,Wu, Qin,Zhao, Yun,Jiao, Qingze,Shi, Daxin
, p. 21415 - 21421 (2015)
A novel basic polymerized ionic liquid (BPIL): polymeric 1-[(4-ethenylphenyl)methyl]-3-propylimidazolium imidazolide was synthesized and characterized by Fourier transform infrared (FT-IR), nuclear magnetic resonance (NMR) and electron spray ionization ma
Highly Active Copper(I)-Chalcogenone Catalyzed Knoevenagel Condensation Reaction Using Various Aldehydes and Active Methylene Compounds
Mannarsamy, Maruthupandi,Prabusankar, Ganesan
, (2021/10/05)
First copper(I) chalcogenones catalysed Knoevenagel Condensation reactions have been reported. No illustration of the utilization of this copper-chalcogenone complex class in Knoevenagel Condensation catalysis can be found. Thus, copper(I) bis(benzimidazole-2-chalcogenone) catalysts [Cu(L1)4]+BF4? (1) and [Cu(L2)4]+BF4? (2) (L1 = bis(1-isopropyl-benzimidazole-2-selone)-3-ethyl; L2 = bis(1-isopropyl-benzimidazole-2-thione)-3-ethyl) have been utilized as catalysts in the Knoevenagel Condensation reactions. These copper(I) chalcogenone catalysts have shown high efficiency for the catalytic Knoevenagel Condensation of aryl aldehydes and active methylene compounds. In particular, complex 2, exhibit the best catalytic activities. The scope of the catalytic reactions has been investigated with 22 different molecules. The excellent catalytic activity has been depicted for various types of substrates with either electron-rich or deficient aryl aldehydes. The present investigation features relatively mild reaction conditions with good functional group tolerance and excellent yields. Graphic Abstract: The first copper(I)-chalcogenone complexes catalysed Knoevenagel Condensation reactions?have also been investigated, and revealed the best catalytic activities. [Figure not available: see fulltext.]
Biguanide-functionalized hierarchical porous covalent organic frameworks for efficient catalysis of condensation reactions
Feng, Huiru,Gong, Kai,Li, Cunhao,Li, Haoran,Wang, Yunyun,Zhang, Daquan,Zhang, Huimin
, (2021/07/21)
Covalent organic frameworks (COFs) can be rationally designed with desired physicochemical properties for a far-ranging application in catalytic systems. Herein, a biguanide-functionalized covalent organic framework was designed and prepared via N-alkylat
Highly active zinc oxide-supported lithium oxide catalyst for solvent-free Knoevenagel condensation
Basude, Manohar,Bhongiri, Yadagiri,Masula, Keshavulu,Pasala, Vijay Kumar,Puppala, Veerasomaiah,Sunkara, Prasad
, (2021/07/09)
Li2O/ZnO catalyst was prepared by wet impregnation method and characterized by XRD, SEM, EDX, FTIR, BET surface area and UV-Vis diffuse reflectance spectroscopy. This study revealed a decrease in average particle size and change in the shape of
Engineering cellulose into water soluble poly(protic ionic liquid) electrolytes in the DBU/CO2/DMSO solvent system as an organocatalyst for the Knoevenagel condensation reaction
Shen, Yuqing,Yuan, Chaoping,Zhu, Xianyi,Chen, Qin,Lu, Shenjun,Xie, Haibo
, p. 9922 - 9934 (2021/12/24)
The facile design and preparation of polyelectrolytes is a frontier topic in the fields of polymer science, energy storage devices and catalysis. Herein, linear water soluble cellulosic poly(protic ionic liquid) (CPIL) electrolytes were facilely and atom economically prepared after the dissolution of cellulose in the newly developed DBU/CO2/DMSO solvent system, followed by the simple addition of succinic anhydride under mild conditions. The DBU not only participated in the dissolution of cellulose as a solvent component, but also acted as an organocatalyst for the acylation reaction of cellulose with succinic anhydride, as well as a cation component in the targeted CPIL electrolytes. The reaction was optimized, and the effect of the reaction conditions on the chemical and physical properties of the CPILs was investigated. And then, as a proof of concept, the CPIL electrolyte aqueous solution was successfully used as the catalytic reaction media for the Knoevenagel condensation reaction. It was found that the reaction was homogeneous at the beginning, and the products could precipitate out from the media with the proceeding of the reaction, thus affording satisfactory filtration yields ranging from 56.7% to 93.8%. The solution properties of the CPIL aqueous solution were primarily investigated towards an in-depth understanding of the catalytic mechanism, by which a synergetic catalytic mechanism of the CPILs was proposed, and the reaction started with a nucleophilic addition reaction, and was then followed by a fast dehydration reaction. Finally, the direct reusability potential of the CPIL aqueous solution after the product filtration was also primarily investigated for the Knoevenagel condensation reaction.
Bis [hydrazinium (1+)] hexafluoridosilicate:(N2H5)2SiF6 novel hybrid crystal as an efficient, reusable and environmentally friendly heterogeneous catalyst for Knoevenagel condensation and synthesis of biscoumari
El hajri, Fatima,Benzekri, Zakaria,Sibous, Sarra,Ouasri, Ali,Boukhris, Said,Hassikou, Amina,Rhandour, Ali,Souizi, Abdelaziz
, (2021/02/03)
A simple, effective, green and nontoxic protocol was used for the Knoevenagel condensation and the biscoumarin derivatives synthesis. It have demonstrated that the use of a new hybrid crystal as a heterogeneous catalyst makes it possible to obtain several
Introduction of bis-imidazolium dihydrogen phosphate as a new green acidic ionic liquid catalyst in the synthesis of arylidene malononitrile, ethyl (E)-3-(aryl)-2-cyanoacrylate and tetrahydrobenzo[b]pyran derivatives
Rahmatizadeh-Pashaki, Zahra,Daneshvar, Nader,Shirini, Farhad
, p. 2135 - 2149 (2021/02/01)
In this work, [H2-Bisim][H2PO4]2 as a novel bis-imidazole-based acidic ionic liquid has been synthesized and characterized with a variety of techniques including FT-IR, 1H, 13C, 31/su
A facile microwave-assisted Knoevenagel condensation of various aldehydes and ketones using amine-functionalized metal organic frameworks
Lee, Ik-Mo,Lumbiny, Bilkis Jahan,Taher, Abu
, (2020/07/16)
An amine-functionalized metal organic framework (MOF) was used as highly efficient and recyclable heterogeneous catalyst for Knoevenagel condensation of various aromatic aldehydes and ketones in ethanol. The catalytic efficiency was demonstrated by the hi
