140241-90-3Relevant articles and documents
LiCl catalyzed Knoevenagel condensation: Comparative study of conventional method vs microwave irradiation
Sabitha, Gowravaram,Subba Reddy,Babu, R. Satheesh,Yadav
, p. 773 - 774 (1998)
LiCl catalyzes the condensation of aromatic aldehydes with active methylene compounds either in NMP or DMF at room temperature or under microwave irradiation in dry media to produce olefinic products in high yields.
Synthesis and characterization of P4VP/SBA-15 composite by in situ polymerization
Kolahdoozan, Majid,Kalbasi, Roozbeh Javad,Shahzeidi, Zohreh S.
, p. 325 - 334 (2012)
Poly(4-vinylpyridine)/SBA-15 (P4VP/SBA-15) composites with various amounts of SBA-15 were prepared and characterized. The physical and chemical properties of P4VP/SBA-15 were investigated by XRD, BET, FT-IR, TGA, and SEM techniques. The catalytic performa
Polyoxoniobates as a superior Lewis base efficiently catalyzed Knoevenagel condensation
Xu, Qiaofei,Niu, Yanjun,Wang, Guan,Li, Yingguang,Zhao, Yuan,Singh, Vikram,Niu, Jingyang,Wang, Jingping
, p. 93 - 99 (2018)
The outstanding basicity of negative charged Lindqvist type Polyoxoniobate K7HNb6O19·13H2O (Nb6) have been proved experimentally as well as by theoretical NBO calculations, the results insights high electron density on terminal and bridging oxygen atoms of niobate anion. The most negative Natural Bond Orbital charge (NBO) of oxygen in Nb6 is ?1.001, which is a much more negative value than those reported in other polyoxometalates, that corroborates its high basicity thus likely to be employed as a strong base catalyst. Experimental study suggests that Nb6 can efficiently catalyze Knoevenagel condensation of various carbonyl compounds with active methylene compounds neglecting the steric and electronic effect of aromatic aldehydes under mild conditions. Kinetic test shows that Knoevenagel condensation of benzaldehyde with ethyl cyanoacetate exhibits second-order kinetics in the presence of Nb6 and the calculated activation energy is 43.3 kJ mol?1. Meanwhile, a proper mechanism according to the NBO study speculates that the most negative charged terminal oxygens in Nb6 would be pivotal in this transformation.
The Knoevenagel condensation of aromatic aldehydes with malononitrile or ethyl cyanoacetate in the presence of CTMAB in water
Wang,Ren,Cao,Tong
, p. 673 - 677 (2001)
A new route of Knoevenagel condensation of aldehydes with malononitrile or ethyl cyanoacetate in the presence of CTMAB in water is described. CTMAB is the most effective catalyst to increase yield among CTMAB, BTEAC and TBAI.
Simple, efficient, and green procedure for the knoevenagel condensation catalyzed by ethylenediammonium diacetate under solvent-free conditions
Zhou, Zhongqiang,Sun, Yong
, p. 3162 - 3168 (2011)
A simple, efficient, and green procedure for Knoevenagel condensation of aromatic aldehydes with malononitrile and ethyl cyanoacetate catalyzed by ethylenediammonium diacetate under solvent-free conditions at room temperature is reported. This method give
Schiff base structured acid-base cooperative dual sites in an ionic solid catalyst lead to efficient heterogeneous knoevenagel condensations
Zhang, Mingjue,Zhao, Pingping,Leng, Yan,Chen, Guojian,Wang, Jun,Huang, Jun
, p. 12773 - 12782 (2012)
An acid-base bifunctional ionic solid catalyst [PySaIm]3PW was synthesized by the anion exchange of the ionic-liquid (IL) precursor 1-(2-salicylaldimine)pyridinium bromide ([PySaIm]Br) with the Keggin-structured sodium phosphotungstate (Na
Isocyanate-functionalized starch as biorenewable backbone for the preparation and application of poly(ethylene imine) grafted starch
Fu, Lixia,Peng, Yanqing
, p. 1547 - 1554 (2017)
Reactive supports provide versatile platforms for surface decoration, affording various functional materials widely used in chemical and biological research. Considering the biodegradability, biocompatibility, and economy, starch is a suitable support med
Diethylamine functionalized polyethylene glycol as a novel and efficient catalyst for Knoevenagel condensation
Ye, Wen,Jiang, Hong,Yang, Xian-Cao
, p. 331 - 334 (2011)
The Knoevenagel condensation of aromatic aldehydes with active methylene is an efficient reaction for carbon-carbon double bond formation. A rapid, efficient, and ecofriendly protocol for the Knoevenagel condensation of active methylene compounds with ald
Mechanically fabricated Metal–organic framework/resin composite nanoparticles for efficient basic catalysis
Zhang, Zhi-Hui,Qian, Bing-Bing,Sheng, Pan-Pan,Yang, Sen,Huang, Xian-Feng,Wang, Jin-Long,Chen, Qun,Wang, Liang,He, Ming-Yang
, (2019/01/16)
Zeolitic imidazolate framework-8 (ZIF-8) was successfully composited with an anionic basic resin 201?×?7 (717-resin) to provide a novel ZIF-8/717-resin composite. Its catalytic activity toward the Knoevenagel condensation reaction was evaluated. Results s
Synthesis of multifunctional polymer containing Ni-Pd NPs via thiol-ene reaction for one-pot cascade reactions
Javad Kalbasi, Roozbeh,Mesgarsaravi, Niloofar,Gharibi, Reza
, (2019/02/03)
Recently, acid–base bifunctional catalysts have been considered due to their abilities, such as the simultaneous activation of electrophilic and nucleophilic species and their high importance in organic syntheses. However, the synthesis of acid–base catalysts is problematic due to the neutralization of acidic and basic groups. This work reports a facial approach to solve this problem via the synthesis of a novel bifunctional polymer using inexpensive materials and easy methods. In this way, at the first step, heterogeneous poly (styrene sulfonic acid-n-vinylimidazole) containing pentaerythritol tetra-(3-mercaptopropionate) (PETMP) and trimethylolpropane trimethacrylate (TMPTMA) cross-linkers were synthesized in the pores of a mesoporous silica structure using click reaction as a novel bifunctional acid–base catalyst. After that, Ni-Pd nanoparticles supported on poly (styrenesulfonic acid-n-vinylimidazole)/KIT-6 as a novel trifunctional heterogeneous acid–base-metal catalyst was prepared. The prepared catalysts were characterized by various techniques like FT-IR, TGA, ICP-AES, DRS-UV, TEM, FE-SEM, EDS-Mapping, and XRD. The synthesized catalysts were efficiently used as bifunctional/trifunctional catalysts for one-pot, deacetalization-Knoevenagel condensation and one-pot, three-step and a sequential reaction containing deacetalization-Knoevenagel condensation-reduction reaction. It is important to note that the synthesized catalyst showing high chemo-selectivity for the reduction of nitro group, alkenyl double bond and ester group in the presence of nitrile. Moreover, it was found that the different nanoparticles including Ni, Pd, and alloyed Ni-Pd showing different chemo-selectivity and catalytic activity in the reaction.