- Microfluidic origami: A new device format for in-line reaction monitoring by nanoelectrospray ionization mass spectrometry
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Microfluidics is an attractive platform for chemical synthesis because it offers fast reaction times, reduced reagent usage, and the ability to integrate multiple functions on a single device. Digital Microfluidics (DMF) is particularly well-suited for microscale chemical synthesis, as it permits discretized sample handling, allowing for total process control. However, a limitation of DMF-based synthesis is analysis, which is often performed offline. To this end, we have developed "microfluidic origami", a new device format that integrates DMF with in-line analysis by mass spectrometry (MS). This format comprises a DMF platform and a folded nanoelectrospray ionization (nanoESI) emitter formed on a single flexible polyimide film substrate. Additionally, the device contains a two-plate-to-one-plate DMF interface, which allows for straightforward coupling of micro-reaction operations and product delivery to the emitter for analysis. The integrated platform was used to perform the Morita-Baylis-Hillman (MBH) reaction using DMF followed by inline MS analysis for monitoring the reaction progress in real-time. We propose that this platform has potential as a new tool for real-time monitoring of reaction rates and reaction pathways and could be a useful addition to the synthetic organic chemistry laboratory.
- Kirby, Andrea E.,Wheeler, Aaron R.
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Read Online
- Catalytic Asymmetric Conjugate Addition of Indolizines to α,β-Unsaturated Ketones
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A catalytic enantioselective conjugate addition of indolizines to enones is described. The chiral phosphoric acid (S)-TRIP activates α,β-unsaturated ketones, thereby promoting an enantioface-differentiating attack by indolizines. Using this reaction, several alkylated indolizines were synthesized in good yields and with enantiomeric ratios of up to 98:2.
- Correia, José Tiago Menezes,List, Benjamin,Coelho, Fernando
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Read Online
- Propylphosphonic acid anhydride–mediated amidation of Morita–Baylis–Hillman–derived indolizine-2-carboxylic acids
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Propylphosphonic acid anhydride has been successfully used as a coupling agent in the synthesis of a series of indolizine-2-carboxamido derivatives from indolizine-2-carboxylic acid and its 3-acetylated analogue. The acid substrates were obtained by sapon
- Sekgota, Khethobole C,Isaacs, Michelle,Hoppe, Heinrich C,Seldon, Ronnett,Warner, Digby F,Khanye, Setshaba D,Kaye, Perry T
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Read Online
- A kinetic and mechanistic study of the Baylis-Hillman reaction
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Reactions of acrylate esters with pyridinecarboxaldehydes, in the presence of 3-hydroxy-quinuclidine or 1,4-diazabicyclo[2.2.2] octane, have been followed by 1H NMR spectroscopy, and a mechanism which accommodates the kinetic data hase been presented.
- Bode, Moira L.,Kaye, Perry T.
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Read Online
- Microwave-assisted convenient syntheses of 2-indolizine derivatives from Morita-Baylis-Hillman adducts: New in silico potential ion channel modulators
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In this work, a microwave-assisted synthesis study by microwave irradiation to produce indolizine-2-carbonitrile and indolizine-2-carboxylate in good to high yields (70 and 81percent, respectively) in one step from Morita-Baylis-Hillman adducts (MBHA) is presented. These compounds were subsequently transformed to high yields (94 to 100percent, respectively) in three 2-indolizine derivatives. The five synthesized compounds were designed in silico aiming to present potential selective activities as ion channel modulators. These activities were suggested by the score values using Molinspiration Cheminformatics program.
- Cunha, Saraghina M.D.,De Oliveira, Ramon G.,Vasconcellos, Ma?rio L.A.A.
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Read Online
- Selective hydrogenation of indolizines: An expeditious approach to derive tetrahydroindolizines and indolizidines from Morita-Baylis-Hillman adducts
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In this study, we describe the hydrogenation of indolizines derived from Morita-Baylis-Hillman adducts. We demonstrate that functionalized tetrahydroindolizines and indolizidines can be prepared selectively, at low pressure, by simply adjusting the acidity of the medium. Using this simple and straightforward strategy, substituted tetrahydroindolizines and indolizidines were obtained diastereoselectively in high yield.
- Teodoro, Bruno V. M.,Correia, José Tiago M.,Coelho, Fernando
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Read Online
- An Improved Protocol for the Morita-Baylis-Hillman Reaction Allows Unprecedented Broad Synthetic Scope
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The Morita-Baylis-Hillman (MBH) reaction has been stablished as an important C?C bond-forming transformation between carbonyl-containing compounds and activated olefins. However, the slow reaction rate usually observed with electron-rich electrophilic par
- Camilo, Nilton S.,Santos, Hugo,Zeoly, Lucas A.,Fernandes, Fábio S.,Rodrigues, Manoel T.,Silva, Thiago S.,Lima, Samia R.,Serafim, José Cláudio,de Oliveira, Aline S. B.,Carpanez, Arthur G.,Amarante, Giovanni W.,Coelho, Fernando
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supporting information
(2022/01/22)
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- 6,5-Fused Ring, C2-Salvinorin Ester, Dual Kappa and Mu Opioid Receptor Agonists as Analgesics Devoid of Anxiogenic Effects**
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Current common analgesics are mediated through the mu or kappa opioid receptor agonism. Unfortunately, selective mu or kappa receptor agonists often cause harmful side effects. However, ligands exhibiting dual agonism to the opioid receptors, such as to mu and kappa, or to mu and delta, have been suggested to temper undesirable adverse effects while retaining analgesic activity. Herein we report an introduction of various 6,5-fused rings to C2 of the salvinorin scaffold via an ester linker. In vitro studies showed that many of these compounds have dual agonism on kappa and mu opioid receptors. In vivo studies on the lead dual kappa and mu opioid receptor agonist demonstrated supraspinal thermal analgesic activity while avoiding anxiogenic effects in male mice, thus providing further strong evidence in support of the therapeutic advantages of dual opioid receptor agonists over selective opioid receptor agonists.
- Akins, Nicholas S.,Mishra, Nisha,Harris, Hannah M.,Dudhipala, Narendar,Kim, Seong Jong,Keasling, Adam W.,Majumdar, Soumyajit,Zjawiony, Jordan K.,Paris, Jason J.,Ashpole, Nicole M.,Le, Hoang V.
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- Chiral Phosphoric Acid Catalyzed Desymmetrization of Cyclopentendiones via Friedel–Crafts Conjugate Addition of Indolizines
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An organocatalytic highly diastero- and enantioselective Friedel–Crafts conjugate addition of indolizines to prochiral cyclopentenediones has been successfully developed. This desymmetric transformation provides a direct access to the desired indolizine-substituted cyclopentanediones in yields of 62–91% and excellent stereoselectivities. The utility of the approach was demonstrated by diverse late-stage functionalizations through reduction or oxidation. Importantly, the direct sp2 C–H functionalization with nitromethane in one-pot process resulted in the indolizine-linked axially chiral styrene bearing a remote chiral center.
- Ni, Qijian,Zhu, Zhiming,Fan, Yanjun,Chen, Xiaoyun,Song, Xiaoxiao
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supporting information
p. 9548 - 9553
(2021/12/14)
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- NOVEL OXALYL PIPERAZINES ACTIVE AGAINST THE HEPATITIS B VIRUS (HBV)
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The present invention relates generally to novel antiviral agents. Specifically, the present invention relates to compounds which can inhibit the protein(s) encoded by hepatitis B virus (HBV) or interfere with the function of the HBV replication cycle, compositions comprising such compounds, methods for inhibiting HBV viral replication, methods for treating or preventing HBV infection, and processes and intermediates for making the compounds.
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Page/Page column 121
(2020/11/12)
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- NOVEL INDOLIZINE-2-CARBOXAMIDES ACTIVE AGAINST THE HEPATITIS B VIRUS (HBV)
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The present invention relates generally to novel antiviral agents. Specifically, the present invention relates to compounds which can inhibit the protein(s) encoded by hepatitis B virus (HBV) or interfere with the function of the HBV replication cycle, compositions comprising such compounds, methods for inhibiting HBV viral replication, methods for treating or preventing HBV infection, and processes and intermediates for making the compounds.
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Page/Page column 125
(2020/11/12)
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- Discovery of fused heterocyclic carboxamide derivatives as novel α7-nAChR agonists: Synthesis, preliminary SAR and biological evaluation
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The α7 nicotinic acetylcholine receptor (α7 nAChR) has emerged as a promising therapeutic target for schizophrenia. In our previous work, a novel series of α7-nAChR agonists bearing scaffold of indolizine were discovered. To explore the effect of aromaticity on the activity and find more active agents, herein, fused heterocyclic carboxamide derivatives were designed and synthesized in this study. Based on the evaluation by two-electrode voltage clamp in Xenopus oocytes, 27 of the synthesized compounds showed obvious agonism of α7 nAChR. Particularly, compounds 10a and 10e showed significantly higher Emax than EVP-6124. The result illustrated the importance of aromaticity to the activity of agonism. Compound 10a, which showed EC50 of 1.88 μM and Emax of 72.4%, was further characterized comprehensively, including co-application with type II positive allosteric modulator PNU-120596, selectivity with other closely related ligand-gated ion channel, etc. The results showed that 10a showed moderate selectivity over other subtypes such as α4β2 and α3β4 nAChR. 10a evoked α7-like currents that were inhibited by MLA and enhanced in the presence of the α7 PAM PNU-120596. The analysis of binding mode and understanding of structure-activity relationship provided insights to develop more potent novel α7-nAChR agonists.
- Xue, Yu,He, Xiaomeng,Yang, Taoyi,Wang, Yuxi,Liu, Zhenming,Zhang, Guisen,Wang, Yanxing,Wang, Kewei,Zhang, Liangren,Zhang, Lihe
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- Organocatalyzed Decarboxylative Trichloromethylation of Morita–Baylis–Hillman Adducts in Batch and Continuous Flow
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Two protocols for the organocatalyzed decarboxylative trichloromethylation of Morita–Baylis–Hillman (MBH) substrates have been developed. Applying sodium trichloroacetate, as the trichloromethyl anion precursor, in combination with an organocatalyst and a
- Enevoldsen, Martin V.,Overgaard, Jacob,Pedersen, Maja S.,Lindhardt, Anders T.
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supporting information
p. 1204 - 1208
(2018/02/06)
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- Stereoselective and regioselective synthesis of N-substituted methyl 2-((azolyl)methyl)-3-arylacrylates from Baylis–Hillman acetates
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N -Substituted methyl 2-((azolyl)methyl)-3-arylacrylates were synthesized stereo- and regioselectively with one-pot reaction between Baylis–Hillman acetates and a suitable acylazole in the presence of K2 CO3 as a base catalyst. The t
- K?seceli ?zen?, Ay?en,?elik, Ilhami,K?kten, ?ule
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p. 323 - 334
(2017/07/04)
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- 2-indolizine Carbamoyl amine compound and its preparation and use
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The invention discloses a novel 2-indolizine formylamine derivative. The general formula of the novel 2-indolizine formylamine derivative is as shown in a formula (I), wherein the definition of R is specified in the specification. In addition, the inventi
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Paragraph 0112; 0152-0155
(2020/02/07)
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- Synthesis and biological activities of indolizine derivatives as alpha-7 nAChR agonists
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Human α7 nicotinic acetylcholine receptor (nAChR) is a promising therapeutic target for the treatment of schizophrenia accompanied with cognitive impairment. Herein, we report the synthesis and agonistic activities of a series of indolizine derivatives targeting to α7 nAChR. The results show that all synthesized compounds have affinity to α7 nAChR and some give strong agonistic activity, particularly most active agonists show higher potency than control EVP-6124. The docking and structure-activity relationship studies provide insights to develop more potent novel α7 nAChR agonists.
- Xue, Yu,Tang, Jingshu,Ma, Xiaozhuo,Li, Qing,Xie, Bingxue,Hao, Yuchen,Jin, Hongwei,Wang, Kewei,Zhang, Guisen,Zhang, Liangren,Zhang, Lihe
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- HETEROARYL PYRIDONE AND AZA-PYRIDONE COMPOUNDS AS INHIBITORS OF BTK ACTIVITY
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Heteroaryl pyridone and aza-pyridone compounds of Formula I are provided, where one or two of X, X, and Xare N, and including stereoisomers, tautomers, and pharmaceutically acceptable salts thereof, useful for inhibiting Btk kinase, and for treating immune disorders such as inflammation mediated by Btk kinase. Methods of using compounds of Formula I foranddiagnosis, and treatment of such disorders in mammalian cells, or associated pathological conditions, are disclosed.
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Paragraph 0723; 0724
(2015/11/16)
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- ALKYLATED PIPERAZINE COMPOUNDS
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Alkylated piperazine compounds of Formula I are provided, including stereoisomers, tautomers, and pharmaceutically acceptable salts thereof, useful for inhibiting Btk kinase, and for treating immune disorders such as inflammation mediated by Btk kinase. Methods of using compounds of Formula I for in vitro, in situ, and in vivo diagnosis, and treatment of such disorders in mammalian cells, or associated pathological conditions, are disclosed.
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Paragraph 0438; 0439
(2013/05/21)
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- Microwave irradiation or low temperature improved synthesis of antiparasitic morita-baylis-hillman adducts
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It is reported the synthesis of 24 Morita-Baylis-Hillman adducts (3a-3l/6a-6l) using microwave irradiation at 80 °C or conventional protocol at 0 °C to promote the reactions between aromatic aldehydes and methyl acrylate or acrylonitrile (81-99%). It is shown that the reaction of 2-hydroxy(4-bromophenyl)methyl acrylate formation is reversible at 120 °C.
- Claudio Jr.,Silva, Fabio P.L.,De Oliveira, Ramon G.,Subrinho, Fernanda L.,De Andrade, Natalia G.,Vasconcellos, Mario L.A.A.
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scheme or table
p. 2220 - 2224
(2012/02/03)
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- Baylis-Hillman reaction under solvent-free conditions - Remarkable rate acceleration and yield enhancement
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A simple and efficient method has been developed for remarkable rate acceleration and yield enhancement of the Baylis-Hillman reaction under solvent-free "neat conditions" and solvent-less isolation of products. Reaction of equimolar quantities of aldehyd
- Saikia, Monmi,Sarma, Jadab C.
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experimental part
p. 1271 - 1276
(2011/02/24)
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- Efficient synthesis of 16 aromatic Morita-Baylis-Hillman adducts: Biological evaluation on Leishmania amazonensis and Leishmania chagasi
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Sixteen aromatic Morita-Baylis-Hillman adducts (MBHA) 1-16 were efficiently synthesized in a one step Morita-Baylis-Hillman reaction (MBHR) involving commercial aldehydes with methyl acrylate or acrylonitrile (81-100% yields) without the formation of side
- Junior, Claudio G.L.,De Assis, Priscila A.C.,Silva, Fabio P.L.,Sousa, Suervy C.O.,De Andrade, Natalia G.,Barbosa, Ticiano P.,Neris, Patricia L.N.,Segundo, Luiz V.G.,Anjos, Italo C.,Carvalho, Gabriel A.U.,Rocha, Gerd B.,Oliveira, Marcia R.,Vasconcellos, Mario L.A.A.
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experimental part
p. 279 - 284
(2011/02/22)
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- Indolizine studies, part 5: Indolizine-2-carboxamides as potential HIV-1 protease inhibitors[1]
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1,1-Carbonyldiimidazole-promoted coupling of Baylis-Hillman-derived indolizine-2-carboxylic acids with a range of amine and amino acid derivatives has provided access to the corresponding carboxamides in moderate to excellent yield. Copyright
- Tukulula, Matshawandile,Klein, Rosalyn,Kaye, Perry T.
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scheme or table
p. 2018 - 2028
(2010/09/05)
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- Analysis of the concerted metalation-deprotonation mechanism in palladium-catalyzed direct arylation across a broad range of aromatic substrates
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The concerted metalation-deprotonation mechanism predicts relative reactivity and regioselectivity for a diverse set of arenes spanning the entire spectrum of known palladium-catalyzed direct arylation coupling partners. An analysis following an active st
- Gorelsky, Serge I.,Lapointe, David,Fagnou, Keith
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supporting information; experimental part
p. 10848 - 10849
(2009/02/05)
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- Synthesis of chiral 2-hydroxy-1-methylpropanoates by rhodium-catalyzed stereoselective hydrogenation of α-(hydroxymethyl)-acrylate derivatives
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The synthesis of chiral 3-hydroxy-2-methylpropanoic acid esters (e.g., "Roche ester" 3a) based on the rhodium-catalyzed stereoselective hydrogenation of Baylis-Hillman reaction products was investigated. Full conversions and enantioselectivities of up to 99% at a substrate/catalyst ratio of up to 500/1 were achieved by application of bisphospholanes of the catASium M series as ancillary ligands. An interesting kinetic resolution was observed by the diastereoselective hydroxy-directed hydrogenation of related racemic β-branched precursors affording mainly anti-isomers with up to 96%ee.
- Holz, Jens,Schaeffner, Benjamin,Zayas, Odalys,Spannenberg, Anke,Boerner, Armin
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experimental part
p. 2533 - 2543
(2009/09/25)
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- Asymmetric organocatalysed [1,3]-sigmatropic rearrangements
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The first organocatalysed enantioselective [1,3]-sigmatropic O- to N-rearrangement reactions are presented. The reactions take place under regio- and enantioselective control, and are catalysed by cinchona alkaloids. Two reactions have been developed the first one is the rearrangement of imidates to amides, while the other rear rangement occurs from carbamates to amines via a decarboxylation. Both transformations give nitrogen protected β-amino acid derivatives as the product. These novel asymmetric organocatalysed [1,3]-sigmatropic O- to N-rearrangement reactions provide a reliable and efficient synthetic method for obtaining enantioenriched β-amino acid derivates in good yield from racemic starting materials.
- Kobbelgaard, Sara,Brandes, Sebastian,Jorgensen, Karl Anker
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scheme or table
p. 1464 - 1471
(2009/04/04)
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- Magnetic nanoparticle-supported Morita-Baylis-Hillman catalysts
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A magnetic nanoparticle-supported quinuclidine was prepared and evaluated as a recoverable Morita-Baylis-Hillman catalyst. The supported catalyst 2 demonstrated comparable activity with that of DABCO and could be simply recycled with the assistance of an
- Luo, Sanzhong,Zheng, Xiaoxi,Xu, Hui,Mi, Xueling,Zhang, Long,Cheng, Jin-Pei
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p. 2431 - 2434
(2008/09/19)
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- Hydroxyl ionic liquid (HIL)-immobilized quinuclidine for Baylis-Hillman catalysis: Synergistic effect of ionic liquids as organocatalyst supports
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Hydroxyl ionic liquid (HIL) has been explored as a novel support for Baylis-Hillman catalyst. The HIL-supported catalyst showed a better catalytic activity compared to other IL-immobilized catalyst that has no hydroxyl group attached to the IL scaffold. T
- Mi, Xueling,Luo, Sanzhong,Xu, Hui,Zhang, Long,Cheng, Jin-Pei
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p. 2537 - 2544
(2007/10/03)
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- A highly active ionic liquid catalyst for Morita-Baylis-Hillman reaction
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The Morita-Baylis-Hillman reaction is an efficient carbon-carbon bond forming reaction for the preparation of α-methylene-β-hydroxycarbonyl compounds. A new and highly active di-naphthalene imidazolium salt has been synthesized. We have found that 1,3-bis
- Lin, Yu-Sheng,Lin, Chiao-Yang,Liu, Chih-Wei,Tsai, Thomas Y.R.
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p. 872 - 877
(2007/10/03)
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- Study of the Baylis-Hillman reaction in a microreactor environment: First continuous production of Baylis-Hillman Adducts
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The Baylis-Hillman reaction has been optimized for use under microreactor conditions. After optimization, the reaction could be performed continuously and approximately 30% faster compared to batch conditions, however at a quite low flow rate.
- Acke, Davy R. J.,Stevens, Christian V.
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p. 417 - 422
(2012/12/22)
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- Ionic liquid-immobilized quinuclidine-catalyzed Morita-Baylis-Hillman reactions
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(Chemical Equation Presented) The ionic liquid-bound quinuclidine catalyzed Baylis-Hillman reactions were investigated. The IL-supported catalyst showed equally good catalytic activity as compared with its nonimmobilized counterpart. The corresponding Bay
- Mi, Xueling,Luo, Sanzhong,Cheng, Jin-Pei
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p. 2338 - 2341
(2007/10/03)
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- The N,N,N′,N′-tetramethylethylenediamine mediated Baylis-Hillman reaction
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The Baylis-Hillman reaction of aromatic aldehydes with various activated alkenes catalyzed by N,N,N′,N′-Tetramethylethylenediamine (TMEDA) in aqueous medium were reported. The efficiency of this catalyst was examined in comparison with DABCO. It was demon
- Zhao, Sanhu,Chen, Zhaobin
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p. 121 - 127
(2007/10/03)
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- 1-Methylimidazole 3-N-oxide as a new promoter for the Morita-Baylis-Hillman reaction
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The Morita-Baylis-Hillman reaction of aldehydes with α,β- unsaturated ketones can be affected by the Lewis bases. We have found that 1-methylimidazole 3-N-oxide promoted the Morita-Baylis-Hillman reaction of various activated aldehyde compounds in non-sol
- Lin, Yu-Sheng,Liu, Chih-Wei,Tsai, Thomas Y. R.
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p. 1859 - 1861
(2007/10/03)
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- Hexamethylenetetramine as a cheap and convenient alternative catalyst in the Baylis-Hillman reaction: Synthesis of aromatic compounds with anti-malarial activity
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Hexamethylenetetramine (7, HMT) is a cheap alternative catalyst in the Baylis-Hillman reaction between aromatic aldehydes and methyl acrylate or acrylonitrile. The use of 0.1 equiv or 1.0 equiv of HMT proved to be an efficient catalyst for the preparation
- De Souza,Meireles, Bruno A.,Aguiar, Lucia C. S.,Vasconcellos
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p. 1595 - 1600
(2007/10/03)
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- One-pot sequential Baylis-Hillman and Michael reactions
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A new one-pot procedure for the sequential Baylis-Hillman and Michael reactions has been developed to construct two carbon-carbon bonds with three components. This procedure has been applied to combine a variety of aromatic aldehydes, β-unsubstituted acry
- Wang, Wengui,Yu, Marvin
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p. 7141 - 7143
(2007/10/03)
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- Correlation between pKa and reactivity of quinuclidine-based catalysts in the Baylis-Hillman reaction: Discovery of quinuclidine as optimum catalyst leading to substantial enhancement of scope
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The reactivity of a variety of quinuclidine-based catalysts in the Baylis-Hillman reaction has been examined, and a straightforward correlation between the basicity of the base and reactivity has been established, without exception. The following order of
- Aggarwal, Varinder K.,Emme, Ingo,Fulford, Sarah Y.
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p. 692 - 700
(2007/10/03)
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- Titanium isopropoxide as efficient catalyst for the aza-Baylis-Hillman reaction. Selective formation of α-methylene-β-amino acid derivatives
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The direct formation of α-methylene-β-amino acid derivatives is achieved using the aza version of the Baylis-Hillman protocol. The products are readily formed in a three-component one-pot reaction between arylaldehydes, sulfonamides, and α,β-unsaturated c
- Balan, Daniela,Adolfsson, Hans
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p. 2329 - 2334
(2007/10/03)
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- Ultrasound in Baylis-Hillman reactions with aliphatic and aromatic aldehydes: Scope and limitations
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The utilization of ultrasound radiation in the Baylis-Hillman reaction with several aldehydes (aromatics and aliphatics) and different α,β-unsaturated reactants is described. For all aldehydes tested, the utilization of ultrasound sources augmented the reaction rate and the chemical yields. The use of ultrasound with two different catalysts (tri-n-butylphosphine and 1,4-diazabicyclo[2.2.2]octane [DABCO]) was also investigated. It was clearly demonstrated that DABCO is much more effective for catalyzing a Baylis-Hillman reaction under the influence of ultrasound than is tri-n-butylphosphine. No effect on reaction rate was observed when the concentration of DABCO was increased.
- Coelho, Fernando,Almeida, Wanda P.,Veronese, Demetrius,Mateus, Cristiano R.,Silva Lopes, Elizandra C.,Rossi, Rodrigo C.,Silveira, Gabriel P.C.,Pavam, César H.
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p. 7437 - 7447
(2007/10/03)
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- Efficient Baylis-Hillman reaction using stoichiometric base catalyst and an aqueous medium
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A practical and efficient set of conditions were developed using stoichiometric base catalyst, 1,4-diazabicyclo[2,2,2]octane (DABCO), and an aqueous medium to overcome problems commonly associated with the Baylis-Hillman reaction, such as low reaction yields and long reaction time. These simple modifications to the classical conditions, using more base catalyst and an aqueous medium, proved to be successful in converting a variety of aliphatic and aromatic aldehydes to their corresponding Baylis-Hillman products. The inclusion of environmentally friendly water in the reaction solvent was critical for achieving the high yield of Baylis-Hillman adducts. Our deuterium-exchange experiments suggest that the Michael addition adduct formed between DABCO and methyl acrylate is the active intermediate for the Baylis-Hillman reaction in aqueous conditions, and its hydrolysis, a nonproductive side reaction facilitated by the quaternary ammonium ion, leading to the formation of a stable betaine product, consumes both the catalyst and methyl acrylate, making it necessary to add more base catalyst and methyl acrylate.
- Yu,Liu,Hu
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p. 5413 - 5418
(2007/10/03)
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- The aqueous trimethylamine mediated Baylis-Hillman reaction
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Aqueous trimethylamine mediated Baylis-Hillman coupling of alkyl acrylates with aldehydes is described.
- Basavaiah, Deevi,Krishnamacharyulu, Marimganti,Rao, Anumolu Jaganmohan
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p. 2061 - 2069
(2007/10/03)
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- Indolizine Studies. Part 2. Synthesis and NMR Spectroscopic Analysis of 2-Substituted Indolizines
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Thermal cyclisation of 3-acetoxy-3-(2-pyridyl)-2-methylenepropionate esters and related compounds provides convenient access to 2-substituted indolizines.Detailed one- and two-dimensional NMR spectroscopic analysis of the title compounds has facilitated interpretation of their 1H and 13C NMR spectra.
- Bode, Moira L.,Kaye, Perry T.
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p. 1809 - 1814
(2007/10/02)
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- Preparation d'amines allyliques a partir d'acyloxy-3 methylene-2 propionates de methyle substitues en 3 par un groupement aromatique ou heteroaromatique
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The reaction of substituted methyl 3-acetoxy 2-methylene propionates 2 with aliphatic amines gives allylic amines.The E configuration is predominant.The reaction of esters 2 with aniline does not give allylic amines.These amines are prepared by rearrangement of the carbamates which are obtained by the reaction of phenyl isocyanate with methyl 3-hydroxy 2-methylene propionates 1.The primary allylic amines are prepared through the reduction of azides 11.
- Foucaud, Andre,Guemmout, Farid El
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p. 403 - 408
(2007/10/02)
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- RATE ENHANCEMENT EFFECTS IN THE DABCO CATALYSED SYNTHESIS OF HYDROXYALKENOATE ESTERS
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Marked acceleration of the catalytic coupling of aldehydes with methyl acrylate is achieved by varying either the aldehyde or the catalytic system.Rapid and efficient formation of heterocyclic derivatives with significant synthetic potential is described.
- Ameer, Farouk,Drewes, Siegfried E.,Freese, Susan,Kaye, Perry T.
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p. 495 - 500
(2007/10/02)
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