2017-88-1Relevant academic research and scientific papers
A double basic Sr-amino containing MOF as a highly stable heterogeneous catalyst
Leo, Pedro,Orcajo, Gisela,Briones, David,Rodríguez-Diéguez, Antonio,Choquesillo-Lazarte, Duane,Calleja, Guillermo,Martínez, Fernando
, p. 11556 - 11564 (2019)
A novel metal-organic framework (MOF) based on strontium alkaline-earth metal and 2-amino-1,4-benzenedicarboxylic acid (NH2-bdc) has been developed. This material is formed by a linear succession of face-sharing strontium polyhedra bridged by a
Ammonium chloride catalyzed Knoevenagel condensation in PEG-400 as ecofriendly solvent
Waghmare, Smita R.
, p. 849 - 855 (2021/09/28)
A simple and selective green methodology has been successfully developed for Knoevenagel condensation in polyethylene glycol-400 using 10 mol % ammonium chloride as catalyst. The method is applicable to a wide range of aromatic, heteroaromatic and α,β-unsaturated aldehydes. The reactions have been found to be clean and free from the formation of the Michael adduct.
The Modified Clay as a New and Eco-Friendly Catalyst for the Knoevenagel Reaction
Bentahar, S.,Dbik, A.,Khomri, M. El,Lacherai, A.,Messaoudi, N. El,Sabour, A.,Taleb, M. Ait
, p. 1438 - 1444 (2020/10/29)
Abstract: This work aims the synthesis of substituted alkenes via Knoevenagel condensation using the clay collected from the Agadir region and modified by KF as a heterogeneous catalyst (KF-modified clay). In this context, the influence of various paramet
Selenotungstates incorporating organophosphonate ligands and metal ions: synthesis, characterization, magnetism and catalytic efficiency in the Knoevenagel condensation reaction
Ban, Ran,He, Peipei,Kong, Hui,Ma, Pengtao,Niu, Jingyang,Wang, Jiawei,Wang, Jingping,Xu, Qiaofei,Yang, Zongfei
supporting information, p. 7420 - 7425 (2020/06/21)
Three sandwich-type TM-containing (TM = transition metal) organophosphonate-based polyoxotungstate clusters, [TM(H2O)4(SeW6O21)2{Co(OOCCH2NCH2PO3)2}3]12?(TM = Co, Ni), have been successfully synthesized, which are the first reported TM-containing organophosphonate-based selenotungstates. They were structurally characterized by PXRD analyses, IR spectroscopy, TGA analyses,etc. Magnetic measurements show that all three compounds exhibit antiferromagnetic interactions. Besides,Co1can be used as an efficient heterogeneous catalyst in the Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate under mild conditions (60 °C), and exhibits satisfactory conversion (93%) and high selectivity (99%).
Magnetic core-shell dendritic mesoporous silica nanospheres anchored with diamine as an efficient and recyclable base catalyst
Surabhi,Shabir, Javaid,Gupta, Padmini,Sah, Digvijay,Mozumdar, Subho
, p. 21152 - 21166 (2020/12/31)
In the present study, diamine-functionalized magnetic core-shell dendritic mesoporous silica nanospheres have been successfully synthesized by an oil-water biphasic stratification-coating strategy. The shape, size and morphology of the synthesized magnetic nanocatalyst could be characterized by various physicochemical techniques such as, field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The characteristic information about the successful immobilization of various functionalities on the nanospheres could be obtained with the help of X-ray powder diffraction (XRD) patterns, Fourier transform-infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDX) and thermo-gravimetric analysis (TGA). The details about the magnetic behaviour and surface area of the nanocatalyst could be acquired by vibrating sample magnetometry (VSM) and BET surface analysis, respectively. The synthesized diamine-functionalized magnetic nanoparticles were then explored as a highly efficient catalyst for the Knoevenagel condensation and one-pot synthesis of polyhydroquinolines using aromatic/heteroaromatic aldehydes and aliphatic aldehydes with active methylene compounds under very mild conditions. The synthesized magnetic core-shell dendritic mesoporous silica nanospheres had large surface areas. This large surface area and pore volume could facilitate a proper interaction and penetration of the reactant molecules with the basic amine groups present on the dendritic mesoporous silica nanospheres. The supported nanocatalyst revealed no sign of leaching of the amine groups present inside the dendrimers and therefore, could be reused up to nine times without any noteworthy loss in catalytic activity.
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.
Molybdenum oxide nanoparticles as recyclable heterogeneous catalyst for synthesis of arylidene ethyl cyanoacetates
Pourshojaei, Yaghoub,Eskandari, Khalil,Elhami, Elaheh,Asadipour, Ali
, p. 5965 - 5973 (2019/06/14)
This work reports an adapted route to the highly efficient synthesis of arylidene ethyl cyanoacetate derivatives in the presence of catalytic amounts of molybdenum oxide nanoparticles (MoO3 NPs) under green conditions at ambient temperature. From the reaction, a wide range of novel arylidene ethyl cyanoacetates was successfully synthesized with high yields from the Knoevenagel condensation reaction between various aryl aldehydes and ethyl cyanoacetate in the presence of MoO3 nanoparticles. The capability of catalyst to separate from the reaction mixture and then reuse is another advantage of this reaction. Furthermore, obtained products belong to analogous of organic compounds that have shown biological activity, and can be used pharmaceutics.
Amino Acid Amide based Ionic Liquid as an Efficient Organo-Catalyst for Solvent-free Knoevenagel Condensation at Room Temperature
Burate, Pralhad A.,Javle, Balasaheb R.,Desale, Pranjal H.,Kinage, Anil K.
, p. 2368 - 2375 (2019/06/17)
Abstract: Ionic liquids of amino acid amide were synthesized and used as an efficient catalyst for solvent-free Knoevenagel condensation. Synthesized ionic liquids are an environmentally benign, inexpensive, metal free and plays the dual role of solvent as well as an efficient catalyst for Knoevenagel condensation. A wide range of aliphatic, aromatic and heteroaromatic aldehydes easily undergo condensation with malononitrile and ethyl cyanoacetate. The reaction proceeds at room temperature without using any organic solvent and is very fast with good to excellent yield. Additionally, the catalyst is easily separable and recyclable without loss of activity. Graphic Abstract: [Figure not available: see fulltext.].
The Knoevenagel condensation using quinine as an organocatalyst under solvent-free conditions
Jain, Kavita,Chaudhuri, Saikat,Pal, Kuntal,Das, Kalpataru
supporting information, p. 1299 - 1304 (2019/01/21)
The Knoevenagel condensation between active methylene compounds and aromatic carobonyl compounds has been developed using quinine as an organocatalyst to afford various electrophilic alkenes in excellent yields (up to 90%). In the presence of a catalytic amount of quinine (15 mol%), the reaction proceeded at room temperature (RT) under solvent-free conditions. In this green approach, the organocatalyst was recovered and recycled for up to four cycles without appreciable loss of activity.
Hypervalent Iodine(III)-Catalyzed Epoxidation of β-Cyanostyrenes
Mangaonkar, Saeesh R.,Singh, Fateh V.
, p. 4473 - 4486 (2019/11/21)
A convenient approach for the synthesis of β-cyanoepoxides is illustrated by iodine(III)-catalyzed epoxidation of electron-deficient β-cyanostyrenes, wherein the active catalytic iodine(III) species was generated in situ. The epoxidation of β-cyanostyrenes was performed using 10 molpercent PhI as precatalyst in the presence of 2.0 equivalents Oxone as an oxidant and 2.4 equivalents of TFA as an additive at room temperature under ultrasonic radiations. The β-cyanoepoxides were isolated in good to excellent yields in a short reaction time.
