- Effective Heterogeneous MoOx-Modified CeO2 Catalyst for Michael Addition of Dimethyl Malonate to 2-Cyclohexen-1-one
-
Molybdenum oxide-modified cerium oxide (MoOx?CeO2) with 1 wt % Mo acted as an effective and reusable heterogeneous catalyst for Michael addition of dimethyl malonate to 2-cyclohexen-1-one, providing high yield of the target product (
- Tamura, Masazumi,Doi, Yamato,Li, Yingai,Nakagawa, Yoshinao,Tomishige, Keiichi
-
-
Read Online
- Mapping the Surface Groups of Amine-Rich Carbon Dots Enables Covalent Catalysis in Aqueous Media
-
Carbon nanodots stand as the missing link between the molecular and the nanoscale world, owing to the unique molecular-like behavior emerging from their synthetic precursors. A converging set of analytical and spectroscopic data yields a precise inventory
- Amato, Francesco,Bonchio, Marcella,Companyó, Xavier,Dell'Amico, Luca,Filippini, Giacomo,Prato, Maurizio,Ragazzon, Giulio,Rosso, Cristian,Vega-Pe?aloza, Alberto
-
supporting information
p. 3022 - 3037
(2020/11/03)
-
- CpTiCl2-Catalyzed Cross-Coupling between Internal Alkynes and Ketones: A Novel Concept in the Synthesis of Halogenated, Conjugated Dienes
-
A novel concept for the synthesis of halogenated, conjugated dienes is disclosed: the CpTiCl2-catalyzed coupling of keto-alkynes, in the presence of Me3SiBr/Et3N?HBr. This reaction provided five-, six-, and seven-membered
- Roldan-Molina, Esther,Nievas, Maria M.,Navarro, Jorge A. R.,Oltra, J. Enrique
-
supporting information
p. 8296 - 8301
(2020/06/17)
-
- Rhodium-Catalyzed Annelation of Benzoic Acids with α,β-Unsaturated Ketones with Cleavage of C?H, CO?OH, and C?C Bonds
-
In the presence of a [Cp*RhCl2]2 catalyst, the Lewis acid In(OTf)3, and the mild base Na2CO3, aromatic carboxylates and α,β-unsaturated ketones undergo a unique hydroarylation/Claisen/retro-Claisen pr
- Zhang, Guodong,Hu, Zhiyong,Belitz, Florian,Ou, Yang,Pirkl, Nico,Goo?en, Lukas J.
-
supporting information
p. 6435 - 6439
(2019/04/10)
-
- A kind of T-leucine derivative of the chiral amine compound and its preparation method and application
-
The invention discloses a tertiary leucine derived chiral amine compound as well as a preparation method and application thereof. The chiral amine compound contains a tert-butyl group, a primary amine, a secondary amine or a tertiary amine functional group and has the structural formula as shown in the specification; and chiral amine and salts thereof are prepared through simple preparation steps by taking common tert-leucine as the raw material to form the chiral amine compound. The chiral amine and the salts thereof can be used for the asymmetrical Michael additive reaction between alpha, beta-unsaturated ketone and a nucleophilic reagent such as nitrocarbol, malonic ester, substituted oxazolone and the like and the asymmetrical cascade reaction between the alpha, beta-unsaturated ketone and fifth-position unsaturated rhodanine, between fifth-position unsaturated hydantoin and the alpha, beta-unsaturated ketone; and the tertiary leucine derived chiral amine compound has very high catalytic activity and stereoselectivity as well as the highest diastereoselectivity of 30/1 and the highest enantioselectivity of 99%, and is wide in oligomer range.
- -
-
Paragraph 0086; 0087; 0096; 0097
(2017/01/26)
-
- Ti-catalyzed straightforward synthesis of exocyclic allenes
-
Exocyclic allenes constitute useful building blocks in organic synthesis and have recently been identified as key intermediates in the synthesis of natural products. Here the first general method for the most straightforward synthesis of exocyclic allenes
- Munoz-Bascon, Juan,Hernandez-Cervantes, Carmen,Padial, Natalia M.,Alvarez-Corral, Miriam,Rosales, Antonio,Rodriguez-Garcia, Ignacio,Oltra, J. Enrique
-
supporting information
p. 801 - 810
(2014/01/23)
-
- E-factor minimized protocols for the polystyryl-BEMP catalyzed conjugate additions of various nucleophiles to α,β-unsaturated carbonyl compounds
-
Efficient protocols for the addition of carbon-, sulphur- and nitrogen-nucleophiles to α,β-unsaturated carbonyl compounds catalyzed by PS-BEMP have been reported. The adoption of solvent-free conditions (SolFC) was crucial for improving the efficiency of all the processes, while by using an organic reaction medium poor results were obtained. Addition reactions were performed by using equimolar amounts of reagents, and the products were isolated by simple filtration with the minimal amount of organic solvent. This approach allowed the E-factor, a measure of the waste of a reaction, to be minimized. Further waste minimization (95.7% compared to batch protocol) has been accomplished by defining a larger scale continuous-flow protocol operating under SolFC.
- Bonollo, Simona,Lanari, Daniela,Longo, Julie M.,Vaccaro, Luigi
-
supporting information; experimental part
p. 164 - 169
(2012/04/04)
-
- An efficient organocatalytic method for highly enantioselective michael addition of malonates to enones catalyzed by readily accessible primary amine-thiourea
-
A practical and highly enantioselective Michael addition of malonates to enones catalyzed by simple and readily available bifunctional primary amine-thiourea derived from 1,2-diaminocyclohexane is reported. The addition of weak acids and elevated temperature (ca. 50 °C) improved the efficiency of the Michael reaction. This approach enables the efficient synthesis of 1,5-ketoesters with good yields, excellent enantioselectivities (up to 99% ee), and low loading (0.5-5 mol %) of simple chiral primary amine-thiourea catalysts, and is applicable in multigram scale synthesis.
- Dudzinski, Krzysztof,Pakulska, Anna M.,Kwiatkowski, Piotr
-
supporting information; experimental part
p. 4222 - 4225
(2012/09/22)
-
- Benign coupling of reactions and separations with reversible ionic liquids
-
Reversible ionic liquids are a novel class of solvents that combine an effective medium where reactions occur with a 'built-in' separation ability for facile recovery of the products and catalysts, making the solvent available for recycle. We report the utility of these solvents in a number of reactions (Claisen-Schmidt condensation, Heck C-C coupling, and CO2 capture) and discuss the effectiveness of the separation. We also provide insight into the challenges and limitations of using these unique solvent systems to couple reactions and separations.
- Hart, Ryan,Pollet, Pamela,Hahne, Dominique J.,John, Ejae,Llopis-Mestre, Veronica,Blasucci, Vittoria,Huttenhower, Hillary,Leitner, Walter,Eckert, Charles A.,Liotta, Charles L.
-
experimental part
p. 1082 - 1090
(2010/03/30)
-
- Ionic liquids made with dimethyl carbonate: Solvents as well as boosted basic catalysts for the michael reaction
-
This article describes 1) a methodology for the green synthesis of a class of methylammonium and methylphosphonium ionic liquids (ILs), 2) how to tune their acid-base properties by anion exchange, 3) complete neat-phase NMR spectroscopic characterisation
- Fabris, Massimo,Lucchini, Vittorio,Noe, Marco,Perosa, Alvise,Selva, Maurizio
-
experimental part
p. 12273 - 12282
(2010/06/11)
-
- Novel guanidinyl pyrrolidine salt-based bifunctional organocatalysts: application in asymmetric conjugate addition of malonates to enones
-
Novel guanidinyl pyrrolidine salts are useful bifunctional organocatalysts for the asymmetric addition of malonates to enones. These organocatalysts are effective under a wide range of reaction conditions and afford products in high yield and enantioselec
- Riguet, Emmanuel
-
scheme or table
p. 4283 - 4285
(2009/10/26)
-
- An Approach to the Synthesis of Stenine
-
A type 2 N-acylnitroso intramolecular Diels-Alder reaction followed by reductive N - O bond cleavage formed the B and C rings of the Stemona alkaloid stenine. Further elaboration provided the functionalized tricyclic core.
- Zhu, Liang,Lauchli, Ryan,Loo, Mandy,Shea, Kenneth J.
-
p. 2269 - 2271
(2008/02/05)
-
- Electrochemically induced addition reactions in the absence of solvent and supporting electrolyte
-
Solvent- and supporting electrolyte-free electrolysis in a two-compartment cell proved to be effective for the direct electroactivation of C-H acid-containing compounds vs. catalytic addition processes. Michael adducts (including quaternary carbon centres
- Caruso, Tonino,Feroci, Marta,Inesi, Achille,Orsini, Monica,Scettri, Arrigo,Palombi, Laura
-
p. 1942 - 1947
(2007/10/03)
-
- Lewis acid catalyzed conjugate addition and the formation of heterocycles using Michael acceptors under solvent-free conditions
-
Conjugate addition and conjugate-addition-initiated ring closure (CAIRC) reactions of β-dicarbonyl compounds with Michael acceptors have been studied using several Lewis acid catalysts under solvent-free conditions. Excellent chemoselectivity was obtained when various Michael acceptors were treated with several β-dicarbonyl compounds. On the other hand, 2-bromo-2-cyclopentenone and 3-bromo-3-vinyl methyl ketone furnished 2,3-dihydrofurans instead of the 1,4-adducts when treated with the same reagents. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Mekonnen, Alemayehu,Carlson, Rolf
-
p. 2005 - 2013
(2007/10/03)
-
- The synthesis of bicyclo[2.2.2]octan-2,6-dione revisited
-
The cyclisation conditions for the formation of bicyclo[2.2.2]octan-2,6- dione (1) from 3-substituted cyclohexanones 2 and 3 have been re-investigated. Use of a medium consisting of isobutyric anhydride and trifluoroacetic acid resulted in a simplified an
- Widegren, Magnus,Dietz, Melanie,Friberg, Annika,Frejd, Torbjoern,Hahn-Haegerdal, Baerbel,Gorwa-Grauslund, Marie F.,Katz, Mikael
-
p. 3527 - 3530
(2008/02/10)
-
- Fluorine-substituted cyclofenil derivatives as estrogen receptor ligands: Synthesis and structure-affinity relationship study of potential positron emission tomography agents for imaging estrogen receptors in breast cancer
-
In a search for estrogen receptor (ER) ligands to be radiolabeled with fluorine-18 for imaging of ER-positive breast tumors with positron emission tomography (PET), we investigated cyclofenil analogues substituted at the C3 or C4 position of the cyclohexyl group. McMurry coupling of 4,4′- dihydroxybenzophenone with various ketones produced key cyclofenil intermediates, from which C3 and C4 substituents containing alkyl and various oxygen or fluorine-substituted alkyl groups were elaborated. Binding assays to both ERα and ERβ revealed that the C3 site is more tolerant of steric bulk and polar groups than the C4 site, consistent with a computational model of the ERα ligand binding pocket. Fluorine substitution is tolerated very well at some sites, giving some compounds having affinities comparable to or higher than that of estradiol. These fluoro and fluoroalkyl cyclofenils merit further consideration as fluorine-18 labeled ER ligands for PET imaging of ERs in breast tumors.
- Seo, Jai Woong,Comninos, John S.,Chi, Dae Yoon,Kim, Dong Wook,Carlson, Kathryn E.,Katzenellenbogen, John A.
-
p. 2496 - 2511
(2007/10/03)
-
- Magnesium-lanthanum mixed metal oxide: A strong solid base for the michael addition reaction
-
Michael additions were achieved quantitatively at room temperature with a broad spectrum of acceptors and donors, using a magnesium-lanthanum mixed oxide, a strong solid base. The best solvent for the reaction is dimethylformamide, but good yields were al
- Veldurthy, Bhaskar,Clacens, Jean Marc,Figueras, Francois
-
p. 767 - 771
(2007/10/03)
-
- High surface area MgO as a highly effective heterogeneous base catalyst for michael addition and knoevenagel condensation reactions
-
Magnesium oxide (MgO), obtained using a novel but simple procedure, was systematically investigated as a heterogeneous base catalyst for reactions taking place in the liquid phase, specifically the Michael addition and the Knoevenagel condensation. The ac
- Xu, Chunli,Bartley, Jonathan K.,Enache, Dan I.,Knight, David W.,Hutchings, Graham J.
-
p. 3468 - 3476
(2007/10/03)
-
- 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) catalyzed Michael reactions
-
1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD), a bicyclic guanidine base, has been found to be an excellent catalyst for Michael and Michael-type reactions. A wide variety of Michael donors and acceptors can participate in these reactions using 10-20 mol % of
- Ye, Weiping,Xu, Junye,Tan, Chin-Tong,Tan, Choon-Hong
-
p. 6875 - 6878
(2007/10/03)
-
- An innovative strategy for electrochemically-promoted addition reactions
-
A new strategy based on the catalytic release of the supporting electrolyte agent in the electrolysis medium proved to be effective for the direct electroactivation of suitable C-H acid-containing compounds vs. catalytic addition processes, under solvent-
- Palombi, Laura,Feroci, Marta,Orsini, Monica,Inesi, Achille
-
p. 1846 - 1847
(2007/10/03)
-
- A versatile synthesis of bicyclo[2.2.2]octan-2-one derivatives
-
A novel sequence for the synthesis of substituted bicyclo[2.2.2]oct-5-en-2-one derivatives starting from substituted cyclohex-2-en-1-ones is presented. The Michael addition of malonic esters to an α,β-unsaturated ketone and an intramolecular aldol reactio
- Schmoldt, Philip,Mattay, Jochen
-
p. 1071 - 1078
(2007/10/03)
-
- Catalytic C-C bond formation promoted by Mg-Al-O-t-Bu hydrotalcite
-
Mg-Al-O-t-Bu-hydrotalcite catalyst was found to be an efficient, environmentally attractive and selective solid base catalyst for 1,4 Michael addition. Mg-Al-O-t-Bu hydrotalcite is also effective for simple synthesis of α,β-unsaturated esters and nitriles by condensation of the corresponding activated carboxylic esters or nitriles with various aldehydes by Knoevenagel condensation. These reactions proceeded at room temperature at a greater rate in the presence of Mg-Al-O-t-Bu hydrotalcite than in the presence of any of the other catalysts examined. (C) 2000 Elsevier Science Ltd.
- Choudary,Lakshmi Kantam,Kavita,Venkat Reddy,Figueras
-
p. 9357 - 9364
(2007/10/03)
-
- Incorporation of La3+ in an organic network. A polyphenol-derived solid bronsted-base catalyst
-
Treatment of anthracenebisresorcinol 1 (a tetraphenol) with La(OiPr)3 in THF affords an amorphous 1:2 (14- to La3+) coordination polymer (La host). It catalyzes typical base-promoted reactions such as Michael, n
- Saiki, Toshiyuki,Aoyama, Yasuhiro
-
p. 797 - 798
(2007/10/03)
-
- Asymmetric Michael addition of malonate anions to prochiral acceptors catalyzed by L-proline rubidium salt
-
L-Proline rubidium salt catalyzes the asymmetric Michael addition of malonate anions to prochiral enones and enals. This method can be applied to a wide range of substrates to give adducts with a predictable absolute configuration: (S)-adducts from (E)-enones/enals and (R)-adducts from cyclic (Z)-enones. Both the secondary amine moiety and the carboxylate moiety are critical for the catalytic activity and asymmetric induction. Varying the countercation also affects the reaction course. High enantiomeric excesses were attained when di(tert-butyl) malonate was added to (E)-enones in the presence of CsF. The stereochemistry of the Michael reaction indicates that asymmetric induction takes place via enantioface discrimination involving the acceptor α-carbon atom rather than the β-carbon atom.
- Yamaguchi, Masahiko,Shiraishi, Tai,Hirama, Masahiro
-
p. 3520 - 3530
(2007/10/03)
-
- Michael reaction of stabilized carbon nucleophiles catalyzed by [RuH2(PPh3)4]
-
The Michael reaction of active methylene compounds lacking cyano groups such as malonates, β-ketoesters, 1,3-diketones, 1,1-disulfones, nitrocompounds, Meldrum acid, and anthrone with common acceptors proceeds in acetonitrile solution in the presence of [RuH2(PPh3)4] as the catalyst. Cyano acetates, more acidic than malonates in organic solvents, are also excellent substrates for this reaction. In a number of cases, intramolecular aldol reactions catalyzed by [RuH2(PPh3)4] were also observed as side reactions. Catalysis by other ruthenium and rhodium complexes has been examined. Selectivity studies performed with malonate and disulfone donors indicate that the catalyst selectively activates Michael donors that can coordinate with ruthenium(II). Additionally, it has been shown that the reaction requires the presence of free phosphine. Therefore, the Michael reaction of stabilized enolates appears to be a ruthenium- and phosphine-catalyzed reaction. From a practical point of view, the use of readily prepared [RuH2(PPh3)4] as the catalyst in acetonitrile provided the best solution for the Michael reaction of active methylene compounds.
- Gómez-Bengoa, Enrique,Cuerva, Juan M.,Mateo, Cristina,Echavarren, Antonio M.
-
p. 8553 - 8565
(2007/10/03)
-