- Interaction of hydroxylamine with esters of 2-oxobutenoic acids. Synthesis of 1-hydroxy-3-hydroximino-2-pyrrolidinones
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New 3-hydroximino-1-hydroxy-2-pyrrolidinones have been synthesized by the interaction of NH2OH and NH2OBn with the methyl esters of 2-oxo-3-butenoic acid derivatives. Some intermediate compounds have been isolated and identified and
- Katkevics,Korchagova,Ivanova,Slavinska,Lukevics
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- Stereo- and Regioselective [3+3] Annulation Reaction Catalyzed by Ytterbium: Synthesis of Bicyclic 1,4-Dihydropyridines
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An ytterbium catalyzed formal [3+3] cycloaddition of cyclic enamines and α,β-unsaturated ketones catalyzed is reported. The reaction proceeds with a ‘head to tail’ regioselectivity through a conjugate addition of the enamine moiety followed by an amine-carbonyl condensation. In addition the use of chiral enamines provided a high degree of stereoselectivity, driven by a possible balance between steric and π-stacking effects. The resulting bicyclic 1,4-dihydropyridines were evaluated as antiproliferative agents against A549 (carcinomic human alveolar basal epithelial cell) and SKOV3 (human ovarian carcinoma) human tumor cell lines. Good toxicities were found for some of the compounds against A549 and SKOV3 cell lines, with best IC50 values of 0.89 μM for A549 and 6.69 μM for SKOV3, and a very good selectivity was observed towards MRC5 (non-malignant) cell lines. (Figure presented.).
- del Corte, Xabier,López-Francés, Adrián,de Marigorta, Edorta Martínez,Palacios, Francisco,Vicario, Javier
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supporting information
p. 4761 - 4769
(2021/08/23)
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- Asymmetric Construction of α-Substituted β-Hydroxy Lactones via Ni Catalyzed Decarboxylative Addition Reaction
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We described a Ni-bidentate oxazoline catalyzed highly enantio- and diastereoselective decarboxylative aldol reaction of 2-oxotetrahydrofuran-3-carboxylic acid/2-oxochromane-3-carboxylic acid derivatives with different kinds of carbonyls. Under optimal reaction conditions, α-substituted β-hydroxy butyrolactones and dihydrocoumarins with an all-carbon quaternary stereocenter have been generated with high levels of functional-group compatibility. Furthermore, proficient transformations of products were also described, in which an aliphatic tertiary alcohol and a multi-substituted 1,4-diol were smoothly constructed through hydrogenation and ring-opening reaction, respectively.
- He, Lingchen,Ahmed, Ebrahim-Alkhalil M. A.,Liu, Hongxin,Hu, Xingen,Xiao, Hong-Ping,Li, Juan,Jiang, Jun
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p. 4825 - 4834
(2021/04/02)
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- A Heck reaction/photochemical alkene isomerization sequence to prepare functionalized quinolines
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A route to prepare functionalized quinolines based on a Heck reaction/UV-induced alkene isomerization sequence is described. The method allows for the preparation of quinolines under mild and neutral conditions and has broad functional group tolerance. Acid-sensitive functional groups that would not be tolerated under previous approaches can be included and a one-pot quinoline forming procedure is also reported.
- Donohoe, Timothy J.,Hoff, Oskar,Hoffman, Jack B.,Kelly, Alex,Walker, Johannes C. L.,Werrel, Simon
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- Asymmetric Catalytic Formal 1,4-Allylation of β,γ-Unsaturated α-Ketoesters: Allylboration/Oxy-Cope Rearrangement
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A highly enantioselective formal conjugate allyl addition of allylboronic acids to β,γ-unsaturated α-ketoesters has been realized by employing a chiral NiII/N,N′-dioxide complex as the catalyst. This transformation proceeds by an allylboration/oxy-Cope rearrangement sequence, providing a facile and rapid route to γ-allyl-α-ketoesters with moderate to good yields (65–92 %) and excellent ee values (90–99 % ee). The isolation of 1,2-allylboration products provided insight into the mechanism of the subsequent oxy-Cope rearrangement reaction: substrate-induced chiral transfer and a chiral Lewis acid accelerated process. Based on the experimental investigations and DFT calculations, a rare boatlike transition-state model is proposed as the origin of high chirality transfer during the oxy-Cope rearrangement.
- Tang, Qiong,Fu, Kai,Ruan, Peiran,Dong, Shunxi,Su, Zhishan,Liu, Xiaohua,Feng, Xiaoming
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supporting information
p. 11846 - 11851
(2019/07/19)
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- Direct Synthesis of β,γ-Unsaturated α-Keto Esters from Aldehydes and Pyruvates
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Herein, we describe two practical methods to synthesize β,γ-unsaturated α-keto esters directly from aldehydes and pyruvates promoted by BF 3 ?Et 2 O in the presence of Ac 2 O or by Ti(OEt) 4 under mild condition
- Mansaray, John Kamanda,Sun, Jiarui,Huang, Shisheng,Yao, Weijun
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supporting information
p. 809 - 813
(2019/04/25)
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- A Catalytic Cross-Olefination of Diazo Compounds with Sulfoxonium Ylides
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A ruthenium-catalysed cross-olefination of diazo compounds and sulfoxonium ylides is presented. Our reaction design exploits the intrinsic difference in reactivity of diazo compounds and sulfoxonium ylides as both carbene precursors and nucleophiles, which results in a highly selective reaction.
- Neuhaus, James D.,Bauer, Adriano,Pinto, Alexandre,Maulide, Nuno
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p. 16215 - 16218
(2018/11/23)
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- Facile synthesis of substituted diaryl sulfones: Via a [3 + 3] benzannulation strategy
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A base-mediated [3 + 3] benzannulation strategy for the conversion of 1,3-bis(sulfonyl)propenes and β,γ-unsaturated α-ketoesters to diaryl sulfones has been developed. This method provides facile, metal-free and efficient access to highly substituted diaryl sulfones in good to excellent yields. In addition, the sulfonyl group could be easily removed or converted to other functional groups via an organostannane intermediate.
- Tang, Xiang-Zheng,Tong, Lang,Liang, Hua-Ju,Liang, Jie,Zou, Yong,Zhang, Xue-Jing,Yan, Ming,Chan, Albert S. C.
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supporting information
p. 3560 - 3563
(2018/05/26)
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- Enantioselective NHC-catalysed redox [4+2]-hetero-Diels-Alder reactions using α-aroyloxyaldehydes and unsaturated ketoesters
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N-Heterocyclic carbene (NHC)-catalysed redox [4+2]-hetero-Diels-Alder reactions of α-aroyloxyaldehydes with either β,γ-unsaturated α-ketoesters or α,β-unsaturated γ-ketoesters generates substituted syn-dihydropyranones in good yield with excellent enantioselectivity (up to >99:1 er). The product diastereoselectivity is markedly dependent upon the nature of the unsaturated enone substituent. The presence of either electron-neutral or electron-rich aryl substituents gives excellent diastereoselectivity (up to >99:5 dr), while electron-deficient aryl substituents give reduced diastereoselectivity. In these cases, the syn-dihydropyranone products are more susceptible to base-promoted epimerisation at the C(4)-position under the reaction conditions, accounting for the lower diastereoselectivity obtained.
- Taylor, James E.,Davies, Alyn T.,Douglas, James J.,Churchill, Gwydion,Smith, Andrew D.
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p. 355 - 366
(2017/02/15)
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- Boosting Chemical Stability, Catalytic Activity, and Enantioselectivity of Metal-Organic Frameworks for Batch and Flow Reactions
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A key challenge in heterogeneous catalysis is the design and synthesis of heterogeneous catalysts featuring high catalytic activity, selectivity, and recyclability. Here we demonstrate that high-performance heterogeneous asymmetric catalysts can be engineered from a metal-organic framework (MOF) platform by using a ligand design strategy. Three porous chiral MOFs with the framework formula [Mn2L(H2O)2] are prepared from enantiopure phosphono-carboxylate ligands of 1,1′-biphenol that are functionalized with 3,5-bis(trifluoromethyl)-, bismethyl-, and bisfluoro-phenyl substituents at the 3,3′-position. For the first time, we show that not only chemical stability but also catalytic activity and stereoselectivity of the MOFs can be tuned by modifying the ligand structures. Particularly, the MOF incorporated with -CF3 groups on the pore walls exhibits enhanced tolerance to water, weak acid, and base compared with the MOFs with -F and -Me groups. Under both batch and flow reaction systems, the CF3-containing MOF demonstrated excellent reactivity, selectivity, and recyclability, affording high yields and enantioselectivities for alkylations of indoles and pyrrole with a range of ketoesters or nitroalkenes. In contrast, the corresponding homogeneous catalysts gave low enantioselectivity in catalyzing the tested reactions.
- Chen, Xu,Jiang, Hong,Hou, Bang,Gong, Wei,Liu, Yan,Cui, Yong
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supporting information
p. 13476 - 13482
(2017/10/05)
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- Catalytic Generation of Donor-Acceptor Cyclopropanes under N-Heterocyclic Carbene Activation and their Stereoselective Reaction with Alkylideneoxindoles
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Formylcyclopropanes undergo activation in the presence of an N-heterocyclic carbene catalyst generating a donor-acceptor cyclopropane intermediate with the ability to undergo ring-opening followed by formal [4+2] cycloaddition with alkylideneoxindoles. This enables the direct enantio- and diastereoselective synthesis of tetrahydropyrano[2,3-b]indoles through the use of a chiral NHC catalyst. (Figure presented.).
- Prieto, Liher,Sánchez-Díez, Eduardo,Uria, Uxue,Reyes, Efraím,Carrillo, Luisa,Vicario, Jose L.
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supporting information
p. 1678 - 1683
(2017/05/22)
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- A New Strategy for Enantioselective Construction of Multisubstituted Five-Membered Oxygen Heterocycles via a Domino Michael/Hemiketalization Reaction
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A new highly enantioselective domino Michael/hemiketalization reaction of α-hydroxyacetophenone with β,γ-unsaturated α-keto esters for the synthesis of 2,2,4,5-tetrasubstituted chiral tetrahydrofurans is reported. With 2 mol% intramolecular dinuclear zinc
- Hua, Yuan-Zhao,Liu, Meng-Meng,Huang, Pei-Jin,Song, Xixi,Wang, Min-Can,Chang, Jun-Biao
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supporting information
p. 11994 - 11998
(2015/08/18)
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- Catalytic enantioselective inverse electron demand hetero-diels-alder reaction with allylsilanes
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The first diastereo- and enantioselective inverse electron demand hetero-Diels-Alder reaction of β,γ-unsaturated α-ketoesters with allylsilanes is described. Chiral copper(II) catalysts successfully activate the β,γ-unsaturated α-ketoesters and promote the reaction with allylsilanes with excellent enantioselectivities. This process represents a new entry to chiral oxanes.
- Matsumura, Yuki,Suzuki, Takahiro,Sakakura, Akira,Ishihara, Kazuaki
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supporting information
p. 6131 - 6134
(2014/06/23)
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- Organocatalysed synthesis of isoxazolines initiated by a chemoselective oxa-Michael reaction of N-BocNHOH
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An organocatalysed and chemoselective one-pot oxa-Michael-cyclocondensation reaction of N-BocNHOH to unsaturated α-ketoesters is reported which affords an original entry to enantioenriched 3-isoxazoline carboxylate derivatives as biorelevant heterocyclic
- Noel,Gembus,Levacher,Briere
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supporting information
p. 1245 - 1249
(2014/03/21)
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- Enantioselective copper(I/II)-catalyzed conjugate addition of nitro esters to β,γ-unsaturated α-ketoesters
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A highly enantioselective Michael addition of nitroacetates to β,γ-unsaturated α-ketoesters was developed by using chiral copper catalysts. The Michael addition products can be obtained in high yields with up to 99 % ee. With these densely functionalized products, the chiral cyclic nitrones, which are important synthetic intermediates, can be obtained in one step. Copyright
- Zhang, Sheng,Xu, Kun,Guo, Fengfeng,Hu, Yanbin,Zha, Zhenggen,Wang, Zhiyong
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supporting information
p. 979 - 982
(2014/02/14)
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- Efficient enantioselective synthesis of dihydropyrans using a chiral N, N ′-dioxide as organocatalyst
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The bifunctional organocatalyst C3 N,N′-dioxide has been successfully applied to the asymmetric cascade Michael/hemiacetalization reaction of α-substituted cyano ketones and β,γ-unsaturated α-ketoesters for the synthesis of multifunctionalized chiral dihydropyrans. The corresponding products were obtained in excellent yields (up to 99%) with high to excellent enantioselectivities (up to 99% ee).
- Feng, Juhua,Fu, Xuan,Chen, Zhenling,Lin, Lili,Liu, Xiaohua,Feng, Xiaoming
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supporting information
p. 2640 - 2643
(2013/07/19)
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- Metal-free michael-addition-initiated three-component reaction for the regioselective synthesis of highly functionalized pyridines: Scope, mechanistic investigations and applications
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A metal-free and completely regioselective three-component synthesis of highly functionalized pyridines from 1,3-dicarbonyl derivatives and Michael acceptors has been achieved. Activated Michael acceptors, that is, β,γ-unsaturated α-oxo carbonyl derivatives, were utilized, allowing substitution at the 4-position and remarkable functional diversity at the 2-position of the pyridine ring. The scope and limitations of this environmentally friendly domino reaction are disclosed, with full experimental data, and the results of mechanistic investigations are discussed. The three-component synthesis of polysubstituted pyridines starting from 1,3-dicarbonyl compounds, α,β-unsaturated carbonyl derivatives and ammonium acetate has been studied, including the scope and mechanism. This methodology is a rare example of a totally regioselective multicomponent access to highly substituted pyridines that complies with many of the stringent criteria of sustainable chemistry. Copyright
- Allais, Christophe,Lieby-Muller, Frederic,Rodriguez, Jean,Constantieux, Thierry
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supporting information
p. 4131 - 4145
(2013/07/19)
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- Enantioselective copper-catalyzed conjugate addition of trimethylaluminium to β,γ-unsaturated α-ketoesters
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Not a cop out: The copper-catalyzed asymmetric conjugate addition of organometallic reagents to Michael acceptors is an important methodology for forming a C-C bond in an enantioselective manner. Such an addition of Me 3Al to β,γ-unsaturated α-
- Gremaud, Ludovic,Alexakis, Alexandre
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supporting information; experimental part
p. 794 - 797
(2012/03/09)
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- Organocatalytic Functionalization of carboxylic acids: Isothiourea- catalyzed asymmetric intra- and intermolecular Michael addition-lactonizations
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Tetramisole promotes the catalytic asymmetric intramolecular Michael addition-lactonization of a variety of enone acids, giving carbo- and heterocyclic products with high diastereo- and enantiocontrol (up to 99:1 dr, up to 99% ee) that are readily derivatized to afford functionalized indene and dihydrobenzofuran carboxylates. Chiral isothioureas also promote the catalytic asymmetric intermolecular Michael addition-lactonization of arylacetic acids and α-keto-β,γ-unsaturated esters, giving anti-dihydropyranones with high diastereo- and enantiocontrol (up to 98:2 dr, up to 99% ee).
- Belmessieri, Dorine,Morrill, Louis C.,Simal, Carmen,Slawin, Alexandra M. Z.,Smith, Andrew D.
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supporting information; experimental part
p. 2714 - 2720
(2011/04/23)
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- Asymmetric Friedel-Crafts alkylation of activated benzenes with methyl (E)-2-oxo-4-aryl-3-butenoates catalyzed by [Pybox/Sc(OTf)3]
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The asymmetric Friedel-Crafts reaction between methyl (E)-2-oxo-4-aryl-3-butenoates (1a-c) and activated benzenes (2a-d) has been efficiently catalyzed by the ScIII triflate complex of (4′S,5′S)-2,6-bis[4′-(triisopropylsilyl) oxymethyl-5′-pheny
- Faita, Giuseppe,Mella, Mariella,Toscanini, Marco,Desimoni, Giovanni
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body text
p. 3024 - 3029
(2010/06/14)
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- Asymmetric friedel-crafts alkylation of indoles with methyl (E)-2-Oxo-4-aryl-3-butenoates catalyzed by Sc(OTf)3/pybox
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The asymmetric Friedel-Crafts reaction between a series of substituted indoles 2a-1 and methyl (E)-2-oxo-4-aryl-3-butenoates 3a-c has been efficiently catalyzed by the scandium-(III) triflate complex of (4′S,5′S)-2,6- bis[4′-(triisopropylsilyl)oxymethyl-5
- Desimoni, Giovanni,Faita, Giuseppe,Toscanini, Marco,Boiocchi, Massimo
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experimental part
p. 3630 - 3636
(2009/05/07)
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- Asymmetrie aerobic oxidation of α-hydroxy acid derivatives by C 4-symmetric, vanadate-centered, tetrakisvanadyl(V) clusters derived from N-salicylidene-α-aminocarboxylates
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(Chemical Equation Presented) A series of chiral vanadyl(V) methoxides bearing 3-t-butyl-5-substituted N-salicylene-L-valinate and L-t-leucinate as chiral auxiliaries has been prepared. In all cases except the 3,5-di-t-butyl analogue, they exist as monomers both in solution and in the single crystal state. In the case of the 3,5-di-t-butyl analogue, the architectural nature of the vanadyl(V) complex highly depends on the base used during the complex formation event. A pentanuclear C4-symmetric complex was formed when potassium salts were employed instead of the corresponding sodium salts. A central vanadate(V) unit serves to grip four identical chiral monomelic vanadyl(V) units together, by which a potassium ion sits on top of the four flanking units through carbonyl coordinations and serves to hold the whole cluster by cooperation with the central vanadate(V) unit. In comparison with the corresponding monomelic vanadyl(V) methoxide complex, the cluster complex was utilized to facilitate the asymmetric aerobic oxidations of various racemic α-hydroxyesters, -amides, and -thioesters with excellent selectivity factors (krel 40 to >500).
- Chen, Chien-Tien,Bettigeri, Sampada,Weng, Shiue-Shien,Pawar, Vijay D.,Lin, Ya-Hui,Liu, Cheng-Yuan,Lee, Way-Zen
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p. 8175 - 8185
(2008/02/13)
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- Peri- and enantioselectivity of thermal, scandium-, and [Pybox/Scandium]-catalyzed diels-alder and hetero-diels-alder reactions of methyl (E)-2-Oxo-4-aryl-butenoates with cyclopentadiene
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The cycloaddition between methyl (E)-2-oxo-4-aryl-3-butenoates (2a-d) and cyclopentadiene, in addition to the expected normal Diels-Alder (DA) adducts endo-3a-d and exo-4a-d, gives the less expected endo-5a-d products of the [4 + 2] heteroDiels-Alder (HDA
- Desimoni, Giovanni,Faita, Giuseppe,Toscanini, Marco,Boiocchi, Massimo
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p. 9478 - 9485
(2008/12/22)
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- Skraup-Doebner-Von Miller quinoline synthesis revisited: Reversal of the regiochemistry for γ-aryl-β,γ-unsaturated α-ketoesters
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A reversal of the standard regiochemistry of the Skraup-Doebner-Von Miller quinoline synthesis was observed when anilines were condensed with γ-aryl-β,γ-unsaturated α-ketoesters in refluxing TFA. The reaction is proposed to involve 1,2-addition of the ani
- Wu, Yan-Chao,Liu, Li,Li, Hui-Jing,Wang, Dong,Chen, Yong-Jun
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p. 6592 - 6595
(2007/10/03)
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- Deracemisation of aryl substituted α-hydroxy esters using Candida parapsilosis ATCC 7330: Effect of substrate structure and mechanism
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Candida parapsilosis ATCC 7330 was found to be an efficient biocatalyst for the deracemisation of aryl α-hydroxy esters (65-85% yield and 90-99% ee). A variety of aryl and aryl substituted α-hydroxy esters were synthesized to reflect steric and electronic effects on biocatalytic deracemisation. The mechanism of this biocatalytic deracemisation was found to be stereoinversion.
- Baskar,Pandian,Priya,Chadha, Anju
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p. 12296 - 12306
(2007/10/03)
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- BUTENOIC ACID DERIVATIVES, PROCESSES FOR THE PREPARATION THEREOF, PHARMACEUTICAL COMPOSITIONS COMPRISING THEM, AND USE FOR THE TREATMENT OF DYSLIPIDAEMIA, ATHEROSCLEROSIS AND DIABETES
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The present invention relates to butenoic acid derivatives of the formula (I) in which R, R1, R2 and R3 are as defined in the description, and also to processes for the preparation thereof, to pharmaceutical compositions c
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Page/Page column 19-20
(2008/06/13)
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- A straighforward route to E-γ-aryl-α-oxobutenoic esters by one-step acid-catalysed crotonisation of pyruvates
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A new and highly simple method for the synthesis of E-γ-aryl-α-oxobutenoic esters is described. This unprecedented one-step procedure is based on an unexpected nucleophilic reactivity of alkyl pyruvates towards aromatic aldehydes in refluxing dichloromethane, when using catalytic amounts of Cu(OTf)2 and in the presence of stoichiometric amounts of trimethyl orthoformate in the case of electron-rich aldehydes. Under these conditions, yields obtained are uniformly higher than those obtained by previous multistep procedures.
- Dujardin,Leconte,Bénard,Brown
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p. 147 - 149
(2007/10/03)
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- A Novel Catalytic and Highly Enantioselective Approach for the Synthesis of Optically Active Carbohydrate Derivatives
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A catalytic enantioselective inverse-electron demand hetero-Diels-Alder reaction of α,β-unsaturated carbonyl compounds with electron-rich alkenes catalyzed by chiral bisoxazolines in combination with Cu(OTf)2 as the Lewis acid is presented. The reaction of γ-substituted β,γ-unsaturated α-keto esters with vinyl ethers and various types of cis-disubstituted alkenes proceeds in good yield, high diastereoselectivity, and excellent enantioselectivity. The potential of the reaction is demonstrated by the synthesis of optically active carbohydrates such as spiro-carbohydrates, an ethyl β-D-mannoside tetraacetate, and acetal-protected C-2-branched carbohydrates. On the basis of X-ray crystallographic data and the absolute configuration of the products, it is proposed that the alkene approaches the si-face of the reacting α,β-unsaturated carbonyl functionality when coordinated to the catalyst.
- Audrain, Helene,Thorhauge, Jacob,Hazell, Rita G.,Jorgensen, Karl Anker
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p. 4487 - 4497
(2007/10/03)
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The alkyl vinyl ethers 2b-8b (deriving from the alcohols 2a-8a) smoothly reacted with methyl E-benzylidenepyruvate 10 in the presence of catalytic amounts of Eu(fod)3 or Yb(fod)3 in refluxing hexane, thus leading to the dihydropyran
- Dujardin, Gilles,Rossignol, Sandrine,Molato, Samira,Brown, Eric
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p. 9037 - 9050
(2007/10/02)
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- Asymmetric syntheses of substituted dihydropyrans by Diels-Alder heterocycloadditions involving chiral vinyl ethers as dienophiles
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The alkyl vinyl ethers 2b-8b (deriving from the alcohols 2a-8a) smoothly reacted with methyl E-benzylidenepyruvate 1 in the presence of catalytic amounts of Eu(fod)3, thus leading to the endo cycloadducts 9-15 in high yields. The cycloadducts 1
- Dujardin,Molato,Brown
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p. 193 - 196
(2007/10/02)
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- On the Use of 3-Bromopropyne as a Reagent for the Introduction of the Pyruvate Moiety
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In the presence of metallic zinc 3-bromopropyne reacts with aldehydes to give homopropynylic alcohols which are converted to the corresponding bromohomopropynylic acetates by acetylation followed by reaction with N-bromosuccinimide and a catalytic quantity of silver acetate; these derivatives are then oxidized to γ-acetoxy-α-ketoesters with osmium tetroxide and tert-butyl hydroperoxide resulting in a convenient four step sequence for the introduction of the pyruvate moiety.
- Chen, Chen,Crich, David
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p. 1289 - 1290
(2007/10/02)
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- Peracid Oxidation of 4-Isoxazolines as a Method for the Preparation of α, β-Unsaturated Carbonyl Compounds
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A study of the MCPBA peracid oxidation of a series of 4-isoxazolines has been carried out.A variety of isoxazolines were synthesized by treating nitrones with electron-deficient alkynes.An alternate approach involves dipolar cycloaddition of nitrones with activated allenes followed by a subsequent base-catalyzed isomerization of the initially formed cycloadduct.Treatment of the 5-exo-methyleneisoxazolidine derived from the reaction of N-benzylidenemethylamine N-oxide and (phenylsulfonyl)propadiene with LDA followed by γ-alkylation also produced substituted 4-isoxazolines.The peracid oxidation of the isoxazoline ring afforded α,β-unsaturated carbonyl compounds in excellent yield.Reductive cleavage of the sulfonyl group of some of the enones was achieved by initial protection of the carbonyl functionality by cyanosilylation using trimethylsilyl cyanide, and this was followed by aluminum-amalgam reduction.The cycloaddition-oxidation procedure provides an attractive route to synthesize α,β-unsaturated ketones since it avoids acidic or basic conditions.
- Padwa, Albert,Chiacchio, Ugo,Kline, Donald N.,Perumattam, John
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p. 2238 - 2245
(2007/10/02)
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- ISOXAZOLINE OXIDATION. AN EFFICIENT METHOD FOR THE PREPARATION OF α,β-UNSATURATED CARBONYL COMPOUNDS
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MCPBA peracid oxidation of Δ4-isoxazolines derived from the dipolar cycloaddition reaction of nitrones with acetylenes or allenes produces α,β-unsaturated ketones in excellent yield.
- Padwa, Albert,Kline, Donald N.,Perumattam, John
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p. 913 - 916
(2007/10/02)
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