- Stereoselective, nitro-Mannich/lactamisation cascades for the direct synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles
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A versatile nitro-Mannich/lactamisation cascade for the direct stereoselective synthesis of heavily decorated 5-nitropiperidin-2-ones and related heterocycles has been developed. A highly enantioenriched substituted 5-nitropiperidin-2-one was synthesised in a four component one-pot reaction combining an enantioselective organocatalytic Michael addition with the diastereoselective nitro- Mannich/lactamisation cascade. Protodenitration and chemoselective reductive manipulation of the heterocycles was used to install contiguous and fully substituted stereocentres in the synthesis of substituted piperidines.
- Jakubec, Pavol,Cockfield, Dane M.,Helliwell, Madeleine,Raftery, James,Dixon, Darren J.
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Read Online
- Enantioselective Michael addition of malonate esters to nitroolefins organocatalyzed by diaryl-2-pyrrolidinemethanols
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Bis-(3,5-dimethylphenyl)((S)-pyrrolidin-2-yl)methanol, easily prepared from l-proline, was found to be an efficient bifunctional organocatalyst, amongst the different 2-pyrrolidinemethanols tested, for the enantioselective Michael addition of malonate est
- Lattanzi, Alessandra
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Read Online
- Asymmetric synthesis of 3-prenyl-substituted pyrrolidin-2-ones
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Pharmacology-relevant compounds bearing structural fragments of racetam nootropics, wound-healing acyclic isoprenoids and neurotropic GABA analogues, were enantioselectively (up to 94% ee) synthesized from available and inexpensive precursors.
- Sukhanova, Anna A.,Nelyubina, Yulia V.,Zlotin, Sergei G.
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Read Online
- Silylation of γ,γ-bis(alkoxycarbonyl)-substituted aliphatic nitro compounds: Synthesis of N,N-bis(trimethylsilyloxy)aminocyclopropanes
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Silylation of γ,γ-bis(alkyloxycarbonyl)-β-aryl- and γ,γ-bis(alkyloxycarbonyl)-β-alkyl-substituted aliphatic nitro compounds proceeds stereoselectively to give the corresponding N,N-bis(trimethylsilyloxy)aminocyclopropanes in high yields. These compounds c
- Smirnov,Tishkov,Lyapkalo,Ioffe,Kachala,Strelenko,Tartakovsky
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Read Online
- Application of pentacoordinated spirophosphorane as a new organocatalyst for the Michael addition reaction
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Pentacoordinated spirophosphorane as a simple, effective and novel organocatalyst for the Michael addition reaction has been investigated. The bisaminoacyl spirophosphorane that possessed a thiourea-like moiety and an amine group was applied to the Michae
- Wang, Peipei,Li, Wanjiao,Han, Kehui,Guo, Yanchun,Zhao, Yufen,Cao, Shuxia
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p. 936 - 947
(2021/07/09)
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- Mimicking Enzymes: Asymmetric Induction inside a Carbamate-Based Steroidal Cleft
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Cholic acid has been elaborated into a carbamate-based tripodal architecture, which is able to promote an asymmetric organic transformation inside its chiral cavity. The nature of this steroidal catalyst has been disclosed by quantum-chemical calculations. It comprises the preorganization and confinement of the reagents within the cavity of the steroid to form a supramolecular complex held together by means of cooperative H-bond contacts. This operational mode resembles that of some enzymes.
- Concellón, Carmen,Martín, Judith,Gallegos, Miguel,Fanjul-Mosteirín, Noé,Costales, Aurora,Pendás, ángel Martín,Del Amo, Vicente
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supporting information
p. 3994 - 3997
(2019/06/17)
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- A thiourea-functionalized metal-organic macrocycle for the catalysis of Michael additions and prominent size-selective effect
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A discrete tetranuclear thiourea-based metal-organic macrocycle (MOM) with a large size was constructed by a well-designed organic ligand and nickel(ii) ions via self-assembly. Incorporating thiourea groups as hydrogen-bond donors into a metal-organic com
- Yang, Lu,Zhao, Liang,Zhou, Zhen,He, Cheng,Sun, Hui,Duan, Chunying
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supporting information
p. 4086 - 4092
(2017/03/30)
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- Helical Oligourea Foldamers as Powerful Hydrogen Bonding Catalysts for Enantioselective C-C Bond-Forming Reactions
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Substantial progress has been made toward the development of metal-free catalysts of enantioselective transformations, yet the discovery of organic catalysts effective at low catalyst loadings remains a major challenge. Here we report a novel synergistic
- Bécart, Diane,Diemer, Vincent,Salaün, Arnaud,Oiarbide, Mikel,Nelli, Yella Reddy,Kauffmann, Brice,Fischer, Lucile,Palomo, Claudio,Guichard, Gilles
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supporting information
p. 12524 - 12532
(2017/09/23)
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- Na+ Ions Induce the Pirouetting Motion and Catalytic Activity of [2]Rotaxanes
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We have prepared [2]rotaxanes, the behavior of which as switchable catalysts depends on their pirouetting motion, which can be controlled through the addition and removal of Na+ ions. At least three sequential on/off cycles of a Michael reactio
- Lee, Yong-Jay,Liu, Kuang-Shun,Lai, Chien-Chen,Liu, Yi-Hung,Peng, Shie-Ming,Cheng, Richard P.,Chiu, Sheng-Hsien
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supporting information
p. 9756 - 9760
(2017/07/25)
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- Selective One-Pot Two-Step C?C Bond Formation using Metal–Organic Frameworks with Mild Basicity as Heterogeneous Catalysts
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Copper-ion-exchanged nickel pyrazolate frameworks behave as selective heterogeneous catalysts for the one-pot, two-step (Henry reaction/Michael type addition) synthesis of neuroactive pharmaceutical intermediates starting from nitromethane and benzaldehyde. Tuning the basicity of multifunctional metal–organic framework catalysts through ion exchange with copper(II) cations allows the tandem C?C bond-forming process to be selectively directed towards the desired pharmaceutical intermediate.
- Cirujano, Francisco G.,López-Maya, Elena,Rodríguez-Albelo, Marleny,Barea, Elisa,Navarro, Jorge A. R.,De Vos, Dirk E.
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p. 4019 - 4023
(2017/11/15)
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- Excited-state hydroxide ion release from a series of acridinol photobases
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The excited-state heterolysis of acridinol-based derivatives leads to the release of the OH-ion and the formation of the corresponding acridinium cations. To evaluate the parameters that control the reaction barriers, the kinetics of excited-state OH-release from a series of acridinol photobases were studied using transient absorption spectroscopy. The rate constants were obtained in three solvents (methanol, butanol, and isobutanol), and the data were modeled using Marcus theory. The intrinsic reorganization energies obtained from these fits were found to correlate well with the solvent reorganization energies calculated using dielectric continuum model, suggesting that the excited-state OH-release occurs along the solvent reaction coordinate. Furthermore, the ability of acridinol photobases to photoinitiate chemical reactions was demonstrated using the Michael reaction between dimethylmalonate and nitrostyrene.
- Xie, Yun,Ilic, Stefan,Skaro, Sanja,Maslak, Veselin,Glusac, Ksenija D.
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p. 448 - 457
(2017/12/08)
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- Supported bifunctional thioureas as recoverable and reusable catalysts for enantioselective nitro-Michael reactions
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The catalytic activity of different supported bifunctional thioureas on sulfonylpolystyrene resins has been studied in the nitro-Michael addition of different nucleophiles to trans-β-nitrostyrene derivatives. The activity of the catalysts depends on the l
- Andrés, José M.,Ceballos, Miriam,Maestro, Alicia,Sanz, Isabel,Pedrosa, Rafael
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p. 628 - 635
(2016/07/06)
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- Squaramide-Catalyzed Michael Addition as a Key Step for the Direct Synthesis of GABAergic Drugs
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Enantioselective organocatalytic Michael additions serve as the key step in syntheses of chiral drugs based on γ-aminobutyric acid. The applicability of various squaramide catalysts for these Michael-type reactions has been assessed. Very good results in
- Veverková, Eva,Bilka, Stanislav,Baran, Rastislav,?ebesta, Radovan
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p. 1474 - 1482
(2016/05/24)
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- Divergent Reactivity of Nitrocyclopropanes with Huisgen Zwitterions and Facile Syntheses of 3-Alkoxy Pyrazolines and Pyrazoles
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A novel annulation reaction of trans-2-substituted-3-nitrocyclopropane-1,1-carboxylates with in situ generated Huisgen zwitterions is reported, providing facile synthesis of 3-alkoxy pyrazolines in good yields and high diastereoselectivities. This reactio
- Yang, Changjiang,Liu, Wei,He, Zijian,He, Zhengjie
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supporting information
p. 4936 - 4939
(2016/10/18)
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- CATALYST FOR ORGANIC REACTION AND METHOD OF USE THEREOF
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A catalyst for an organic reaction and a method of using a catalyst in an organic reaction are provided. The catalyst for an addition or condensation reaction includes a graphene oxide including an oxygen functional group, and the catalyst is configured t
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Paragraph 0094; 0116-0117
(2015/05/05)
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- Efficient synthesis of β-aryl-γ-lactams and their resolution with (S)-Naproxen: Preparation of (R)- and (S)-Baclofen
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An efficient synthesis of enantiomerically-pure β-aryl-γ-lactams is described. The principal feature of this synthesis is the practical resolution of β-aryl-γ-lactams with (S)-Naproxen. The procedure is based on the Michael addition of nitromethane to benzylidenemalonates, which was easily obtained, followed by the reduction of the γ-nitroester in the presence of Raney nickel and the subsequent saponification/decarboxylation reaction. The utility of this methodology was highlighted by the preparation of enantiomerically-pure (R)- and (S)-Baclofen hydrochloride.
- Montoya-Balbás, Iris J.,Valentín-Guevara, Berenice,López-Mendoza, Estefanía,Linzaga-Elizalde, Irma,Ordo?ez, Mario,Román-Bravo, Perla
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p. 22028 - 22043
(2016/01/25)
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- Chiral squaramide-functionalized imidazolium-based organic-inorganic hybrid silica promotes asymmetric michael addition of 1,3-dicarbonyls to nitroalkenes in brine
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Chiral cinchona-based squaramide-functionalized organic-inorganic hybrid silica is developed through postgrafting 3-mercaptopropyltrimethoxylsilane onto imidazolium-based organic-inorganic hybrid silica, followed by the anchor of a squaramide organocataly
- Xu, Xiangming,Cheng, Tanyu,Liu, Xiaochen,Xu, Jianyou,Jin, Ronghua,Liu, Guohua
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p. 2137 - 2142
(2014/07/21)
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- Higher enantioselectivities in thiourea-catalyzed Michael additions under solvent-free conditions
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Enantioselective Michael additions catalyzed by hydrogen-bonding catalysts produce many important compounds. Solvent-free reaction conditions in a ball mill can provide an improved enantioselectivity over the reaction in solution, due to lack of disruptiv
- Hestericová, Martina,?ebesta, Radovan
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p. 901 - 905
(2014/01/23)
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- Multisite organic-inorganic hybrid catalysts for the direct sustainable synthesis of GABAergic drugs
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Multisite organic-inorganic hybrid catalysts have been prepared and applied in a new general, practical, and sustainable synthetic procedure toward industrially relevant GABA derivatives. The domino sequence is composed of seven chemical transformations which are performed in two one-pot reactions. The method produces both enantiomeric forms of the product in high enantiopurity as well as the racemate in good yields after a single column purification step. This protocol highlights major process intensification, catalyst recyclability, and low waste generation.
- Leyva-Perez, Antonio,Garcia-Garcia, Pilar,Corma, Avelino
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supporting information
p. 8687 - 8690
(2014/08/18)
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- Mechanosynthesis of γ-nitro dicarbonyl compounds via CaCl 2-catalyzed Michael addition
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An efficient strategy for the mechanosynthesis of γ-nitro dicarbonyl esters has been developed. A CaCl2-catalyzed Michael reaction, conducted at room temperature, afforded nitroalkenes from malonates in a short reaction time and in high yields.
- Jia, Chunman,Chen, Da,Zhang, Chunyan,Zhang, Qi,Cao, Bennan,Zhao, Zhendong
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p. 7320 - 7324
(2013/08/23)
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- An expedient and green protocol for the Michael addition of malonates, diketones and p-keto esters to the nitrostyrenes
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A novel methodology has been developed for the rapid synthesis of functionalized nitroalkanes by the addition of less reactive carbon nucleophiles such as malonate esters, acetylacetone and ethyl acetoacetate to various r/ms-p-nitrostyrenes under solvent-
- Agarwal, Jyoti,Naganaboina, Ram Tilak,Peddinli, Rama Krishna
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p. 511 - 518
(2013/06/05)
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- Graphene oxide as a recyclable phase transfer catalyst
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We demonstrated a simple and green chemical method to obtain Michael adducts and their derivatives by using GO as a phase transfer catalyst with different kinds of bases in water and dichloromethane, and we also used GO multiple cycles almost without redu
- Kim, Youngmin,Some, Surajit,Lee, Hyoyoung
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supporting information
p. 5702 - 5704
(2013/07/11)
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- Iodine-promoted synthesis of 3-arylindolizine-1-carboxylates from 2-(2-nitro-1-arylethyl)malonates and pyridine
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An efficient and straightforward one-pot synthetic protocol has been developed for the synthesis of 3-arylindolizine- 1-carboxylates via 1,3-dipolar annulation of 2-(2-nitro-1-arylethyl)malonates with pyridine and subsequent aromatisation in the presence of molecular iodine. The structure of methyl 3-(4-methoxyphenyl)indolizine-1-carboxylate (2a) and methyl 3-iodo-2-(4- nitrophenyl)indolizine-1-carboxylate (2f) was further confirmed by X-ray single crystal analysis. Website
- Li, Yun,Zhou, Zhengquan,Ye, Weijian,Liu, Juanjuan,Yao, Juan,Wang, Cunde
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p. 526 - 530
(2013/10/22)
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- Polymer-supported enantioselective bifunctional catalysts for nitro-Michael addition of ketones and aldehydes
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Introduction of an L-amino acid as a spacer and a urea-forming moiety in a polymer-supported bifunctional urea-primary amine catalyst, based on (1R, 2R)-(+)-1,2-diphenylethylenediamine, significantly improves the catalyst's activity and stereoselectivity in the asymmetric addition of ketones and aldehydes to nitroolefins. Yields and enantioselectivities, unprecedented for immobilized catalysts, were obtained with such challenging donors as acetone, cyclopentanone, and α,α-disubstituted aldehydes, which usually perform inadequately in this reaction (particularly when a secondary-amine-based catalyst is used). Remarkably, though in the examined catalysts the D-amino acids as spacers were significantly inferior to the L isomers, for the chosen configuration of the diamine (match-mismatch pairs) the size of the side chain of the amino acid hardly influenced the enantioselectivity of the catalyst. These results, combined with the reactivity profile of the catalysts with substrates bearing two electron-withdrawing groups and the behavior of the catalysts' analogues based on tertiary (rather than primary) amine, suggest an enamine-involving addition mechanism and a particular ordered C-C bond-forming transition state as being responsible for the catalytic reactions with high enantioselectivity. Copyright
- Tuchman-Shukron, Lital,Miller, Scott J.,Portnoy, Moshe
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supporting information; experimental part
p. 2290 - 2296
(2012/03/27)
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- Immobilization of 1,5,7-triazabicyclo [4.4.0] dec-5-ene over mesoporous materials: An efficient catalyst for Michael-addition reactions under solvent-free condition
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Immobilization of 1,5,7-triazabicyclo [4.4.0] dec-5-ene (TBD, a bicylic guanidine base) over mesoporous material like SBA-15 has been found to be an excellent catalyst for Michael-addition of β-nitro styrene with malonate. The reactions were performed und
- Kalita, Pranjal,Kumar, Rajiv
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experimental part
p. 250 - 258
(2012/01/05)
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- The immobilisation of chiral organocatalysts on magnetic nanoparticles: The support particle cannot always be considered inert
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A systematic study concerning the immobilisation onto magnetic nanoparticles of three useful classes of chiral organocatalyst which rely on a confluence of weak, easily perturbed van der Waals and hydrogen bonding interactions to promote enantioselective
- Gleeson, Oliver,Davies, Gemma-Louise,Peschiulli, Aldo,Tekoriute, Renata,Gun'Ko, Yurii K.,Connon, Stephen J.
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scheme or table
p. 7929 - 7940
(2011/12/04)
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- Asymmetric organocatalytic Michael addition of Meldrum's acid to nitroalkenes: Probing the mechanism of bifunctional thiourea organocatalysts
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The asymmetric Michael addition of Meldrum's acid to nitroalkenes was studied using a novel type of Cinchona alkaloid-based bifunctional thiourea organocatalyst. The functionality of the thiourea catalysts was also probed by preparing and testing thiourea-N-methylated analogues of the well-known bis-(3,5-trifluoromethyl)phenyl-substituted catalyst. ARKAT USA, Inc.
- Kataja, Antti O.,Koskinen, Ari M. P.
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scheme or table
p. 205 - 223
(2010/08/22)
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- Mechanism and application of a microcapsule enabled multicatalyst reaction
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In this paper, we describe the development and application of a multistep one-pot reaction that is made possible by the site isolation of two otherwise incompatible catalysts. We prepared a microencapsulated amine catalyst by interfacial polymerization and used it in conjunction with a nickel-based catalyst for the transformation of an aldehyde to a Michael adduct via a nitroalkene intermediate. The amine-catalyzed conversion of an aldehyde to a nitroalkene was found to proceed through an imine rather than a nitroalcohol. Kinetic studies indicated that the reaction is first order in both the nickel catalyst and the shell of the encapsulated amine catalyst. Furthermore, we provide evidence against interaction between amine and nickel catalysts and present kinetic data that demonstrates that there is a rate enhancement of the Michael addition due to the urea groups on the surface of the microencapsulated catalyst. We applied our one-pot reaction to the development of a new synthetic route for pregabalin that proceeds with an overall yield of 74%.
- Poe, Sarah L.,Kobaslija, Muris,McQuade, D. Tyler
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p. 9216 - 9221
(2008/02/11)
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- An enantioselective Michael addition of malonate to nitroalkenes catalyzed by low loading demethylquinine salts in water
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An enantioselective Michael addition of malonate to nitroalkenes is efficiently catalyzed by low loading demethylquinine salts in water; the yield range from 49% to 93% and the ee up to 90%.
- Chen, Fu-Xin,Shao, Cheng,Wang, Quan,Gong, Pin,Zhang, Dong-Yan,Zhang, Bang-Zhi,Wang, Rui
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p. 8456 - 8459
(2008/03/13)
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- Microcapsule enabled multicatalyst system
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We present a new microencapsulated catalyst and report its use in a tandem multicatalyst reaction. Using an encapsulation technique, we developed an active, site-isolated amine catalyst that is capable of catalyzing the addition of nitromethane to an aldehyde. When a second Lewis acid catalyst is added, the nitroalkene intermediate is trapped and converted to the corresponding Michael adduct. We show that if the amine catalyst is not encapsulated, the two catalysts cannot function together. Moreover, if the two reactions are performed in sequence rather than in tandem, the first reaction results in an undesired dinitro product and the desired Michael adduct is not formed. Copyright
- Poe, Sarah L.,Kobaslija, Muris,McQuade, D. Tyler
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p. 15586 - 15587
(2007/10/03)
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- The study of reaction mechanism for the transformation of nitronate into nitrile by phosphorus trichloride
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Nitronate was generated using β-nitrostyrene and the anion of dimethyl malonate in THF at 0°C. Subsequent treatment with PCl3 in the presence/absence of DMAP either in THF or pyridine afforded nitroalkane, chloroxime, and nitrile. Pyridine, THF, and THF-pyridine co-solvent as solvents were investigated under different conditions. With different anions of malonates containing dipolarphiles, cyclic compounds were obtained as major products indicating nitrile oxides were generated during the reaction. Based on the results, compared to that of the one reported in literature, a plausible mechanism involving nitrile oxide intermediate was proposed.
- Tu, Zhijay,Jang, Yaochung,Lin, Chunchi,Liu, Ju-Tsung,Hsu, Jianming,Sastry,Yao, Ching-Fa
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p. 10541 - 10551
(2007/10/03)
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- 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) catalyzed Michael reactions
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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
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p. 6875 - 6878
(2007/10/03)
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- Pinene-fused chiral N-ethylpyridinum room temperature molten salts
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New chiral room temperature molten salts (ionic liquids) based on the pinene-pyridinium unit associated with triflate or trifluoroacetate anions were prepared. The thermal behavior of these salts was observed by DSC and solventless 1H NMR spect
- Drahonovsky, Dusan,Labat, Gael Charles,Sevcik, Juraj,von Zelewsky, Alex
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p. 2169 - 2179
(2007/10/03)
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- ASYMMETRIC MICHAEL AND ALDOL ADDITION USING BIFUNCTIONAL CINCHONA-ALKALOID-BASED CATALYSTS
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One aspect of the present invention relates to quinine-based and quinidine-based catalysts. Another aspect of the invention relates to a method of preparing a derivatized quinine-based or quinidine-based catalyst comprising 1) reacting quinine or quinidine with 5 base and a compound that has a suitable leaving group, and 2) converting the ring methoxy group to a hydroxy group. Another aspect of the present invention relates to a method of preparing a chiral, non-racemic compound from a prochiral electron-deficient alkene or azo compound or prochiral aldehyde or prochiral ketone, comprising the step of: reacting a prochiral electron-deficient alkene or azo compound or prochiral aldehyde or prochiral 10 ketone with a nucleophile in the presence of a catalyst; thereby producing a chiral, non racemic compound; wherein said catalyst is a derivatized quinine or quinidine. Another aspect of the present invention relates to a method of kinetic resolution, comprising the step of reacting racemic chiral alkene with a nucleophile in the presence of a derivatized quinine or quinidine.
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Page/Page column 65-66
(2008/06/13)
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- Highly enantioselective conjugate addition of malonate and β-ketoester to nitroalkenes: Asymmetric C-C bond formation with new bifunctional organic catalysts based on cinchona alkaloids
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The development of readily accessible bifunctional chiral catalysts is a desirable yet challenging goal in catalytic asymmetric synthesis. In this communication, we describe the development of a new class of readily accessible chiral bifunctional organic catalysts that could be derived in one or two steps in high yield from either quinidine or quinine. These catalysts have been shown to catalyze a highly enantioselective conjugate addition of methyl and ethyl malonates and β-ketoesters to a broad range of β-substituted nitroalkenes, an synthetically important C-C bond-forming reaction utilizing readily available starting materials. This new catalytic asymmetric reaction proceeds in 91-98% ee and 71-99% yield. Copyright
- Li, Hongming,Wang, Yi,Tang, Liang,Deng, Li
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p. 9906 - 9907
(2007/10/03)
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