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David Gueyrard - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Substituted Indolizidines and Quinolizidines by Regioselective Intramolecular Modified Julia Olefination of Imides.
The Journal of Organic Chemistry, 2019Co-Authors: Bastien Raison, Peter G. Goekjian, Nicolas Dussart, Laura Levy, David GueyrardAbstract:We report the synthesis of substituted indolizidines and quinolizidines using the modified Julia Olefination previously developed on imides. The study focuses on the regioselectivity of this reaction on unsymmetrically substituted imides. The scope and regioselectivity of the reaction are presented here, and its utility as a tool for synthesizing natural products is demonstrated through the total synthesis of Pandalizine A.
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Extension of the Modified Julia Olefination on Carboxylic Acid Derivatives: Scope and Applications
Synlett, 2017Co-Authors: David GueyrardAbstract:This account relates our work in the field of modified Julia Olefination to extend this very useful Olefination method to carboxylic acid derivatives. Since our preliminary results on lactones in 2005, the reaction has been extended to a large range of derivatives (lactams, imides and anhydrides) through an intra- or intermolecular process leading to a great variety of structures (enol ethers, enamides and exo enol esters). This article will also focus on the application of this methodology for the preparation of biologically interesting compounds and/or total syntheses of natural products such as C-disaccharide, bistramide A, jaspine B and maculalactone B.1 Introduction2 Modified Julia Olefination on Lactones2.1 Methylene Enol Ether Synthesis2.2 Substituted Enol Ether Synthesis2.3 Monofluorinated Enol Ether Synthesis2.4 Difluorinated Enol Ether Synthesis3 Applications3.1 Spiroketal Synthesis3.2 Spirocompound Synthesis3.3 Pseudodisaccharide Synthesis3.4 Total Synthesis of Jaspine B4 Modified Julia Olefination on Other Carboxylic Acid Derivatives4.1 Lactam Olefination and Spiroaminal Synthesis4.2 Bicyclic Enamide Synthesis by Intramolecular Modified Julia Olefination on Imides4.3 Modified Julia Olefination on Anhydrides5 Conclusion
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Modified Julia Olefination on Anhydrides: Extension and Limitations. Application to the Synthesis of Maculalactone B
Organic Letters, 2016Co-Authors: Nicolas Dussart, Huu Vinh Trinh, David GueyrardAbstract:The preparation of exo-enol esters from cyclic anhydrides is reported using a modified Julia Olefination. The reaction is highly stereoselective. The Smiles rearrangement can be performed in a one-pot process, giving a straightforward access to exo-enol lactones. Furthermore, the reaction was extended to semistabilized sulfones, and this methodology was applied to the synthesis of maculalactone B.
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Development of a Modified Julia Olefination of Imides for the Synthesis of Alkaloids
European Journal of Organic Chemistry, 2016Co-Authors: Huu Vinh Trinh, Peter G. Goekjian, Lionel Perrin, David GueyrardAbstract:We report the development of the intramolecular Julia Olefination of imides. This original reaction produces N-fused bicyclic enamide compounds, which are interesting precursors in the synthesis of alkaloids. We show that this transformation enables access to [5,6], [6,5], and [6,6] fused bicyclic lactam enamides. The scope and the limitations of the reaction are presented as well as computational studies concerning novel mechanistic aspects of the title reaction.
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Modified Julia Olefination on Anhydrides: Extension and Limitations. Application to the Synthesis of Maculalactone B
2016Co-Authors: Nicolas Dussart, Huu Vinh Trinh, David GueyrardAbstract:The preparation of exo-enol esters from cyclic anhydrides is reported using a modified Julia Olefination. The reaction is highly stereoselective. The Smiles rearrangement can be performed in a one-pot process, giving a straightforward access to exo-enol lactones. Furthermore, the reaction was extended to semistabilized sulfones, and this methodology was applied to the synthesis of maculalactone B
Peter G. Goekjian - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of Substituted Indolizidines and Quinolizidines by Regioselective Intramolecular Modified Julia Olefination of Imides.
The Journal of Organic Chemistry, 2019Co-Authors: Bastien Raison, Peter G. Goekjian, Nicolas Dussart, Laura Levy, David GueyrardAbstract:We report the synthesis of substituted indolizidines and quinolizidines using the modified Julia Olefination previously developed on imides. The study focuses on the regioselectivity of this reaction on unsymmetrically substituted imides. The scope and regioselectivity of the reaction are presented here, and its utility as a tool for synthesizing natural products is demonstrated through the total synthesis of Pandalizine A.
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Development of a Modified Julia Olefination of Imides for the Synthesis of Alkaloids
European Journal of Organic Chemistry, 2016Co-Authors: Huu Vinh Trinh, Peter G. Goekjian, Lionel Perrin, David GueyrardAbstract:We report the development of the intramolecular Julia Olefination of imides. This original reaction produces N-fused bicyclic enamide compounds, which are interesting precursors in the synthesis of alkaloids. We show that this transformation enables access to [5,6], [6,5], and [6,6] fused bicyclic lactam enamides. The scope and the limitations of the reaction are presented as well as computational studies concerning novel mechanistic aspects of the title reaction.
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Synthesis of exo-enamides from protected lactams using a modified Julia Olefination reaction : application to the synthesiss of spiroaminal fragments.
European Journal of Organic Chemistry, 2014Co-Authors: Nicolas Gigant, David Gueyrard, Peter G. Goekjian, Samuel Habib, Marie Medoc, Isabelle GillaizeauAbstract:A modified Julia Olefination (Julia–Kocienski) reaction involving lactams has been developed, which gives the corresponding substituted exo-enamides in moderate to good yields. An application of this versatile transformation in the synthesis of spiroaminal fragments is also demonstrated.
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Synthesis of exo‐Enamides from Protected Lactams Using a Modified Julia Olefination Reaction: Application to the Synthesis of Spiroaminal Fragments
European Journal of Organic Chemistry, 2014Co-Authors: Nicolas Gigant, David Gueyrard, Peter G. Goekjian, Samuel Habib, Marie Medoc, Isabelle GillaizeauAbstract:A modified Julia Olefination (Julia–Kocienski) reaction involving lactams has been developed, which gives the corresponding substituted exo-enamides in moderate to good yields. An application of this versatile transformation in the synthesis of spiroaminal fragments is also demonstrated.
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synthesis of substituted exo glucals via a modified Julia Olefination and identification as selective β glucosidase inhibitors
ChemInform, 2014Co-Authors: Samuel Habib, Peter G. Goekjian, Emmanuel Pfund, Thierry Lequeux, Florent Larnaud, Teresa Mena Barragán, Carmen Ortiz Mellet, David GueyrardAbstract:A series of fluorine and non-fluorine-substituted C-glucosylidenes (III)/(IV) is synthesized as mixtures of (E)/(Z)-isomers via a modified Julia Olefination.
Istvan E Marko - One of the best experts on this subject based on the ideXlab platform.
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metathesis based synthesis of 3 methoxy α β unsaturated lactones total synthesis of r kavain and of the c1 c6 fragment of jerangolid d
Tetrahedron Letters, 2008Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:The total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D has been achieved in nine and seven steps, respectively, from commercially available dimethyl D-Malate. A metathesis reaction of vinyl ethers and a sulfoxide-modified Julia Olefination have been employed as the key steps. (c) 2007 Elsevier Ltd. All rights reserved.
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Metathesis-based synthesis of 3-methoxy α,β-unsaturated lactones: total synthesis of (R)-kavain and of the C1–C6 fragment of jerangolid D
Tetrahedron Letters, 2008Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:The total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D has been achieved in nine and seven steps, respectively, from commercially available dimethyl D-Malate. A metathesis reaction of vinyl ethers and a sulfoxide-modified Julia Olefination have been employed as the key steps. (c) 2007 Elsevier Ltd. All rights reserved.
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Total synthesis of jerangolid D
Journal of the American Chemical Society, 2007Co-Authors: Jiri Pospisil, Istvan E MarkoAbstract:A short and convergent synthesis of jerangolid D is described. As key steps, a Blaise reaction is employed to construct the lactone ring, a diastereoselective multicomponent Sakurai condensation leads to the dihydropyran ring, and the skipped diene is assembled using a modified Julia Olefination.
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total synthesis of r goniothalamin and r goniothalamin oxide first application of the sulfoxide modified Julia Olefination in total synthesis
Tetrahedron Letters, 2006Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:A short and efficient synthesis of (R)-(+)-goniothalamin 1 and (R)-(+)-goniothalamin oxide 2 is described. During this approach, the sulfoxide-modified Julia Olefination was used as a key step to connect aldehyde 5 to sulfoxide 6. The desired styryl-containing adduct is obtained in good yield and with excellent E/Z selectivity. (c) 2006 Elsevier Ltd. All rights reserved.
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Total synthesis of (R)-(+)-goniothalamin and (R)-(+)-goniothalamin oxide: first application of the sulfoxide-modified Julia Olefination in total synthesis
Tetrahedron Letters, 2006Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:A short and efficient synthesis of (R)-(+)-goniothalamin 1 and (R)-(+)-goniothalamin oxide 2 is described. During this approach, the sulfoxide-modified Julia Olefination was used as a key step to connect aldehyde 5 to sulfoxide 6. The desired styryl-containing adduct is obtained in good yield and with excellent E/Z selectivity. (c) 2006 Elsevier Ltd. All rights reserved.
Jiři Pospisil - One of the best experts on this subject based on the ideXlab platform.
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on the origin of e z selectivity in the modified Julia Olefination importance of the elimination step
European Journal of Organic Chemistry, 2013Co-Authors: Raphaël Robiette, Jiři PospisilAbstract:The mechanism and origin of high E selectivity in the modified Julia Olefination of aromatic aldehydes have been explored by computational and experimental means. Reversibility of addition and hence selectivity of the formation of sulfinate 5 is very variable and depends on the nature of the sulfone substrate. However, in all cases, elimination occurs through a concerted antiperiplanar and synperiplanar mechanism for sulfinates anti-5 and syn-5, respectively. Both syn and anti diastereomeric pathways thus lead preferentially to the (E)-alkene. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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On the Origin of E/Z Selectivity in the Modified Julia Olefination – Importance of the Elimination Step
European Journal of Organic Chemistry, 2013Co-Authors: Raphaël Robiette, Jiři PospisilAbstract:The mechanism and origin of high E selectivity in the modified Julia Olefination of aromatic aldehydes have been explored by computational and experimental means. Reversibility of addition and hence selectivity of the formation of sulfinate 5 is very variable and depends on the nature of the sulfone substrate. However, in all cases, elimination occurs through a concerted antiperiplanar and synperiplanar mechanism for sulfinates anti-5 and syn-5, respectively. Both syn and anti diastereomeric pathways thus lead preferentially to the (E)-alkene. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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metathesis based synthesis of 3 methoxy α β unsaturated lactones total synthesis of r kavain and of the c1 c6 fragment of jerangolid d
Tetrahedron Letters, 2008Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:The total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D has been achieved in nine and seven steps, respectively, from commercially available dimethyl D-Malate. A metathesis reaction of vinyl ethers and a sulfoxide-modified Julia Olefination have been employed as the key steps. (c) 2007 Elsevier Ltd. All rights reserved.
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Metathesis-based synthesis of 3-methoxy α,β-unsaturated lactones: total synthesis of (R)-kavain and of the C1–C6 fragment of jerangolid D
Tetrahedron Letters, 2008Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:The total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D has been achieved in nine and seven steps, respectively, from commercially available dimethyl D-Malate. A metathesis reaction of vinyl ethers and a sulfoxide-modified Julia Olefination have been employed as the key steps. (c) 2007 Elsevier Ltd. All rights reserved.
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total synthesis of r goniothalamin and r goniothalamin oxide first application of the sulfoxide modified Julia Olefination in total synthesis
Tetrahedron Letters, 2006Co-Authors: Jiři Pospisil, Istvan E MarkoAbstract:A short and efficient synthesis of (R)-(+)-goniothalamin 1 and (R)-(+)-goniothalamin oxide 2 is described. During this approach, the sulfoxide-modified Julia Olefination was used as a key step to connect aldehyde 5 to sulfoxide 6. The desired styryl-containing adduct is obtained in good yield and with excellent E/Z selectivity. (c) 2006 Elsevier Ltd. All rights reserved.
Samuel Habib - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of exo-enamides from protected lactams using a modified Julia Olefination reaction : application to the synthesiss of spiroaminal fragments.
European Journal of Organic Chemistry, 2014Co-Authors: Nicolas Gigant, David Gueyrard, Peter G. Goekjian, Samuel Habib, Marie Medoc, Isabelle GillaizeauAbstract:A modified Julia Olefination (Julia–Kocienski) reaction involving lactams has been developed, which gives the corresponding substituted exo-enamides in moderate to good yields. An application of this versatile transformation in the synthesis of spiroaminal fragments is also demonstrated.
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Synthesis of exo‐Enamides from Protected Lactams Using a Modified Julia Olefination Reaction: Application to the Synthesis of Spiroaminal Fragments
European Journal of Organic Chemistry, 2014Co-Authors: Nicolas Gigant, David Gueyrard, Peter G. Goekjian, Samuel Habib, Marie Medoc, Isabelle GillaizeauAbstract:A modified Julia Olefination (Julia–Kocienski) reaction involving lactams has been developed, which gives the corresponding substituted exo-enamides in moderate to good yields. An application of this versatile transformation in the synthesis of spiroaminal fragments is also demonstrated.
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synthesis of substituted exo glucals via a modified Julia Olefination and identification as selective β glucosidase inhibitors
ChemInform, 2014Co-Authors: Samuel Habib, Peter G. Goekjian, Emmanuel Pfund, Thierry Lequeux, Florent Larnaud, Teresa Mena Barragán, Carmen Ortiz Mellet, David GueyrardAbstract:A series of fluorine and non-fluorine-substituted C-glucosylidenes (III)/(IV) is synthesized as mixtures of (E)/(Z)-isomers via a modified Julia Olefination.
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Synthesis of Substituted Exo‐Glucals via a Modified Julia Olefination and Identification as Selective β‐Glucosidase Inhibitors.
ChemInform, 2014Co-Authors: Samuel Habib, Peter G. Goekjian, Emmanuel Pfund, Thierry Lequeux, Florent Larnaud, Teresa Mena Barragán, Carmen Ortiz Mellet, David GueyrardAbstract:A series of fluorine and non-fluorine-substituted C-glucosylidenes (III)/(IV) is synthesized as mixtures of (E)/(Z)-isomers via a modified Julia Olefination.
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Synthesis of substituted exo-glucal via a modified Julia Olefination and identification as selective b-glucosidase inhibitors
Organic and Biomolecular Chemistry, 2014Co-Authors: Samuel Habib, Peter G. Goekjian, Florent Larnaud, E Pfund, T Mena Barragán, T Lequeux, C Ortiz Mellet, D. GueyrardAbstract:A series of fluorine and non-fluorine-substituted C-glucosylidenes (exo-glucals) has been synthesized via a modified Julia Olefination. The deprotected exo-glucals were prepared in five steps from commercially available d-gluconolactone. The evaluation of this original family of compounds against a panel of glycosidases showed a highly specific in vitro activity towards mammalian β-glucosidase depending on the double bond substituents.
