6626-84-2Relevant articles and documents
Condensation of β-diester titanium enolates with carbonyl substrates: A combined DFT and experimental investigation
Marrone, Alessandro,Renzetti, Andrea,De Maria, Paolo,Gerard, Stephane,Sapi, Janos,Fontana, Antonella,Re, Nazzareno
, p. 11537 - 11550 (2009)
The condensation of dialkyl β-diesters with various aldehydes promoted by TiCl4 has been studied by DFT approaches and experimental methods, including NMR, IR and UV/ Vis spectroscopy. Various possible reaction pathways have been investigated a
Gadolinium triflate catalyzed alkylation of pyrroles: efficient synthesis of 3-oxo-2,3-dihydro-1H-pyrrolizine derivatives
Unaleroglu, Canan,Yazici, Arife
, p. 5608 - 5613 (2007)
Novel 2-alkylated pyrrole derivatives were synthesized regioselectively by Gd(OTf)3 catalyzed addition reactions of pyrrole to?substituted dimethyl 2-benzylidenemalonate derivatives under mild reaction conditions. 2-Alkylated pyrrole derivative
NbCl5-Promoted Synthesis of 4-Aryl-3,4-dihydrocoumarins by Multicomponent Reaction
Dos Santos, Willian Henrique,Da Silva-Filho, Luiz Carlos
, p. 3361 - 3365,5 (2012)
Substituted 4-aryl-3,4-dihydrocoumarins are synthesized from multicomponent reactions between phenols, dimethyl malonate, and aryl aldehydes catalyzed by niobium pentachloride. This new method is simple, cost-effective, and high-yielding, and can be condu
A novel sublimable organic salt: Synthesis, characterization, thermal behavior, and catalytic activity for the synthesis of arylidene, heteroarylidene, and alkylidene malonates
Johari, Suzaimi,Zaharani, Lia,Gorjian, Hayedeh,Johan, Mohd R.,Khaligh, Nader G.
, p. 361 - 377 (2021/09/18)
A novel sublimable organic salt was synthesized, and its chemical structure was characterized by FTIR, 1D NMR, 2D NMR, and elemental analysis. In addition, the thermal phase transitions and thermal stability of new organic salt were investigated. The DSC and TGA results showed that the organic salt could convert into constituent molecules at dec. ~ 200?°C) under atmospheric pressure without forming the liquid phase. Then, it was recondensed to regenerate the initial organic salt in the cool part of the vial. Therefore, it can be a promising organic salt towards the regeneration of spent catalyst from synthesis processes when the reaction mixture contains poorly volatile components and includes its use in gas-phase procedures. Also, the catalytic efficiency of new organic salt was investigated in the Knoevenagel condensation reaction. A variety of substituted arylidene and alkylidene malonates were isolated in 78–95% yield within six hours.? Under the optimized reaction conditions, the current catalytic procedure exhibited superiority compared to the mixed piperazine/acetic acid, piperidine/acetic acid, and piperidinium acetate. There were no significant changes in the new organic salt chemical structure and catalytic activity even after the 5th run. This work revealed the importance of the existence of simultaneous hydrogen bond acceptor/donor groups in our environmentally friendly catalyst to promote the Knoevenagel condensation reaction without the use of metal-containing catalysts.
Solid-phase synthesis of arylidene and alkylidene malonates, as versatile intermediates, catalyzed using mesoporous poly-melamine–formaldehyde as a nitrogen-rich porous organic polymer (POP)
Khaligh, Nader Ghaffari,Gorjian, Hayedeh,Fahim, Hoda,Titinchi, Salam J. J.
, p. 3529 - 3536 (2021/05/11)
An efficient solid/slurry-state synthesis of arylidene and alkylidene malonates as versatile intermediates is developed in the presence of mesoporous poly-melamine–formaldehyde. The condensation reaction was conducted through a ball milling process as a non-conventional procedure and a greener methodology at room temperature under solvent-free conditions. The mesoporous heterogeneous catalyst could be recovered and reused ten times, and the results showed a negligible loss of catalytic activity. Various aryl- and heteroarylidene malonates, as well as dimethyl (cyclohexylidene)malonate, were isolated in good to high yields under optimal conditions. The use of hazardous reagents and solvents were minimized in the current method, and separation of catalyst and products, as well as the recovery and reusing of catalyst, were performed by cost-effective procedures. This work revealed that the synergistic effect of numerous Lewis base sites together with acceptor-donner hydrogen bonding functional groups in porous organic polymer (POP), and its high porosity plays a vital role to promote the carbon–carbon coupling reaction in the solid phase synthesis.
Chemo- And regioselective ring-opening of donor-acceptor oxiranes with: N -heteroaromatics
Sang, Ji-Wei,Xie, Ming-Sheng,Wang, Man-Man,Qu, Gui-Rong,Guo, Hai-Ming
supporting information, p. 4552 - 4555 (2021/05/17)
The first ring-opening of D-A oxiranes with N-heteroaromatics in a chemoselective C-C bond cleavage manner was achieved. In the presence of 5 mol% of Y(OTf)3 as the catalyst, diverse N-heteroaromatics, including benzotriazoles, purines, substituted benzim
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.
Acetal Addition to Electron-Deficient Alkenes with Hydrogen Atom Transfer as a Radical Chain Propagation Step
Chan, Wei Chuen,Vinod, Jincy K.,Koide, Kazunori
, p. 3674 - 3682 (2021/02/16)
We describe a visible-light-promoted addition of a hydrogen atom and an acetal carbon toward various electron-deficient alkenes. 1,3-Dioxolane is converted to its radical species in the presence of persulfate and an iridium catalyst upon visible light irradiation, which then reacts with electron-deficient alkenes. The reaction operates via a radical chain mechanism, a less commonly observed pathway for this class of transformation. Hydrogen atom transfer from 1,3-dioxolane to α-malonyl radicals is corroborated by experimental and density functional theory studies.
Synthesis of Substituted β-Styrylmalonates by Sequential Isomerization of 2-Arylcyclopropane-1,1-dicarboxylates and (2-Arylethylidene)malonates
Borisov, Denis D.,Chermashentsev, Grigorii R.,Novikov, Roman A.,Tomilov, Yury V.
supporting information, p. 2253 - 2259 (2021/03/04)
A method has been developed for the synthesis of substituted β-styrylmalonates by conversion of 2-arylcyclopropane-1,1-dicarboxylates (ACDCs) in the presence of gallium trichloride into the corresponding- 1,2-zwitterionic intermediates or (2-arylethyl-idene)malonates, followed by treatment with pyridine at room temperature leading to an isomerization of the emerging double bond. This method allows one to expand these reactions to include ACDCs with acceptor substituents at the aromatic ring.
Mild Darzens Annulations for the Assembly of Trifluoromethylthiolated (SCF3) Aziridine and Cyclopropane Structures
Delost, Michael D.,Njardarson, Jon T.
supporting information, p. 6121 - 6125 (2021/08/16)
We report mild new annulation approaches to trisubstituted trifluoromethylthiolated (SCF3) aziridines and cyclopropanes via Darzens inspired protocols. The products of these anionic annulations, rarely studied previously, possess attractive features rendering them valuable building blocks for synthesis platforms. In this study, trisubstituted acetophenone nucleophiles bearing SCF3 and bromine substituents in their α position were shown to undergo [2 + 1] annulations with vinyl ketones and tosyl-protected imines under mild reaction conditions.
