620-80-4Relevant articles and documents
Cs-Beta with an Al-rich composition as a highly active base catalyst for Knoevenagel condensation
Otomo, Ryoichi,Osuga, Ryota,Kondo, Junko N.,Kamiya, Yuichi,Yokoi, Toshiyuki
, p. 20 - 24 (2019)
Ion-exchange of an Al-rich zeolite beta, synthesized by organic structure-directing agent-free method (Beta-OF), was studied for application as a base catalyst. While the as-synthesized Beta-OF in Na-form itself had base sites and showed moderate catalyti
IR-Spectroscopic Study of Adsorption of Aminoazoles on Oxide Catalysts of Biginelli Reaction
Koryakova,Titova, Yu. A.,Murashkevich,Fedorova
, (2018)
Adsorption of 5-aminotetrazole and 3-aminotriazole on the surface of nanosized oxides of Al and Si–Ti, which are catalysts of the Biginelli reaction with the participation of aminoazoles, have been studied using the method of IR spectroscopy. It has been
Knoevenagel condensation reactions catalysed by metal-organic frameworks
Burgoyne, Andrew R.,Meijboom, Reinout
, p. 563 - 571 (2013)
Functionalised metal-organic frameworks (MOFs) which contain amino groups on their secondary building units (SBUs) are basic catalysts in the Knoevenagel condensation. University of Michigan Crystalline Material-1-amine (UMCM-1-NH2), Isoreticul
A benchtop NMR spectrometer as a tool for monitoring mesoscale continuous-flow organic synthesis: Equipment interface and assessment in four organic transformations
Archambault, Cynthia M.,Leadbeater, Nicholas E.
, p. 101171 - 101177 (2016)
An approach is reported for monitoring continuous-flow reactions by means of a low-field benchtop NMR spectrometer. The spectrometer is interfaced with a mesofluidic reactor and used as a tool for optimising four organic transformations, namely an acid-catalysed esterification, a Knoevenagel condensation, a Diels-Alder reaction, and an alkylation. Reactions need to be performed either solvent-free or at relatively high concentration in order to monitor them effectively using the NMR spectrometer, but this allows for the leveraging of one of the key advantages of flow processing, namely process intensification.
Reductive Knoevenagel Condensation with the Zn-AcOH System
Ivanov, Konstantin L.,Melnikov, Mikhail Ya.,Budynina, Ekaterina M.
, p. 1285 - 1291 (2020/11/13)
An efficient gram-scale one-pot approach to 2-substituted malonates and related structures is developed, starting from commercially available aldehydes and active methylene compounds. The technique combines Knoevenagel condensation with the reduction of the C=C bond in the resulting activated alkenes with the Zn-AcOH system. The relative ease with which the C=C bond reduction occurs can be traced to the accepting abilities of the substituents in the intermediate arylidene malonates.
On the enantioselective phosphoric-acid-catalyzed hantzsch synthesis of polyhydroquinolines
Bonne, Damien,Bressy, Cyril,Bugaut, Xavier,Constantieux, Thierry,Jean, Marion,Lemaitre, Clément,Quinonero, Ophélie,Rodriguez, Jean,Roussel, Christian,Vanthuyne, Nicolas
supporting information, p. 3394 - 3398 (2021/05/29)
A reinvestigation of a chiral phosphoric-acid-catalyzed four-component Hantzsch enantioselective synthesis of polyhydroquinolines reported in 2009 is presented. In our hands, when the reaction was performed with fidelity to the original report using a chiral enantiopure phosphoric acid catalyst, no enantioselectivity was observed. Unlike in the original report, enantioselectivity results are backed by baseline separation of the enantiomers by HPLC analyses on chiral stationary phase with UV and chiroptical detection.
Asymmetric Synthesis of Pentasubstituted Cyclohexanes through Diphenylprolinol Silyl Ether Mediated Domino Michael/Michael Reaction
Hayashi, Yujiro,Matoba, Hiroaki,Mori, Naoki,Odoh, Amaechi Shedrack,Umekubo, Nariyoshi,Aidanp??, Louise
supporting information, p. 6670 - 6673 (2021/12/31)
An asymmetric domino Michael/Michael reaction of α,β-unsaturated aldehydes 1 and α-acetyl-β-substituted-α,β-unsaturated esters 2 catalyzed by diphenylprolinol silyl ether was developed. This is a formal carbo [4+2] cycloaddition reaction affording penta-s
Highly active hybrid mesoporous silica-supported base organocatalysts for C–C bond formation
Erigoni,Hernández-Soto,Rey,Segarra,Díaz
, p. 227 - 236 (2019/10/28)
New base hybrid catalysts, based on silyl-derivatives of molecules carrying amino, diamino, pyrrolidine, pyrazolium and imidazolium functionalities have been successfully achieved through post synthetic grafting onto M41S-type support. Different character
Highly efficient FeNP-embedded hybrid bifunctional reduced graphene oxide for Knoevenagel condensation with active methylene compounds
Patel, Dikin,Vithalani, Ravi,Modi, Chetan K.
, p. 2868 - 2881 (2020/03/03)
We have synthesized atypical highly active bifunctional FeNPs implanted on amino-modified reduced graphene oxide (FeNPs/Am@rGO) [where FeNPs = Fe nanoparticles; Am = Primary aromatic amine derivatives such as p-phenylenediamine (PPD) and/or aniline (AN)]
Preparation and characterization of magnetic graphene nanocomposite containing Cu(proline)2 as catalyst for asymmetric aldol reactions
Kooti,Kooshki,Nasiri
, p. 2641 - 2656 (2019/02/14)
A new catalyst has been prepared via immobilization of Cu(proline)2 complex onto the surface of magnetic graphene. The fabricated nanocatalyst was characterized by Fourier-transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (PXRD) analysis, vibrating-sample magnetometry (VSM), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), inductively coupled plasma (ICP) techniques, and elemental analysis. Its catalytic performance was investigated in the aldol reaction using a mild and ecofriendly procedure. The synthesized nanocomposite, which contains Cu(II) center as Lewis acid, was found to be an efficient catalyst for asymmetric aldol reactions, affording corresponding aldol products in high yield and excellent enantiomeric excess (> 90?%). The examined catalyst was prepared from low-cost, easily available starting materials and can be readily isolated by magnetic decantation for recycling and reuse in consecutive reactions without significant loss of activity.