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Janine Cossy - One of the best experts on this subject based on the ideXlab platform.
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stereoselective rearrangement of trifluoromethyl Prolinols to enantioenriched 3 substituted 2 trifluoromethyl piperidines
Organic Letters, 2015Co-Authors: Sarah Rioton, Domingo Gomez Pardo, Aurelie Orliac, Zeina Antoun, Roselyne Bidault, Janine CossyAbstract:3-Substituted 2-(trifluoromethyl)piperidines B were synthesized by ring expansion of (trifluoromethyl)Prolinols A, which were obtained from l-proline via an aziridinium intermediate C. The ring opening of the (trifluoromethyl)aziridinium intermediate by different nucleophiles is regio- and diastereoselective.
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access to optically active 3 substituted piperidines by ring expansion of Prolinols and derivatives
Chemistry: A European Journal, 2014Co-Authors: Domingo Gomez Pardo, Janine CossyAbstract:: The ring expansion of Prolinols via an aziridinium intermediate gives C3-substituted piperidines in good yields and enantiomeric excess, the substituent at the C3 position being derived from the most reactive nucleophile in the reaction mixture. Depending on the nucleophile, the reaction proceeds under thermodynamic or kinetic control. The regioselectivity of attack of nucleophiles on the aziridinium intermediate depends on the nature of the substituents on the nitrogen atom and the C4 position of the starting Prolinols.
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access to optically active 3 aminopiperidines by ring expansion of Prolinols thermodynamic versus kinetic control
European Journal of Organic Chemistry, 2012Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine CossyAbstract:3-Aminopiperidines are of great interest because they can possess a wide range of biological activity depending on the nitrogen substituents. Different approaches their synthesis are presented and the most efficient is a ring expansion of Prolinols induced by XtalFluor-E (diethylaminodifluorosulfinium tetrafluoroborate) in the presence of tetrabutylammonium azide, via an aziridinium intermediate, followed by the reduction of the corresponding azide. Under kinetic conditions, a 2-(azidomethyl)pyrrolidine/3-azidopiperidine ratio of 0:100 can be attained depending on the substituents present on the prolinol.
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access to optically active 3 azido and 3 aminopiperidine derivatives by enantioselective ring expansion of Prolinols
Organic Letters, 2011Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine CossyAbstract:The activation of N-alkyl Prolinols by XtalFluor E allowed the formation of an aziridinium intermediate that can react with tetrabutylammonium azide (nBu4NN3) to produce 3-azidopiperidines and/or 2-(azidomethyl)pyrrolidines, in a ratio up to 100/0. These 3-azidopiperidines can be reduced to the corresponding 3-aminopiperidines.
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enantioselective ring expansionof Prolinols an efficient and short synthesis of 2 phenylpiperidin 3 olderivatives and 3 hydroxypipecolic acids
Synlett, 2009Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine Cossy, Benjamin Burger, Cristina Navarro, Yang Zhao, Theodore CohenAbstract:A very short route to 2-phenylpiperidin-3-ol derivatives and 3-hydroxypipecolic acids is described. The approach uses two key steps: a one-pot reduction/Grignard addition sequence applied to alkyl proline esters and a ring expansion applied to the corresponding Prolinols.
Domingo Gomez Pardo - One of the best experts on this subject based on the ideXlab platform.
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stereoselective rearrangement of trifluoromethyl Prolinols to enantioenriched 3 substituted 2 trifluoromethyl piperidines
Organic Letters, 2015Co-Authors: Sarah Rioton, Domingo Gomez Pardo, Aurelie Orliac, Zeina Antoun, Roselyne Bidault, Janine CossyAbstract:3-Substituted 2-(trifluoromethyl)piperidines B were synthesized by ring expansion of (trifluoromethyl)Prolinols A, which were obtained from l-proline via an aziridinium intermediate C. The ring opening of the (trifluoromethyl)aziridinium intermediate by different nucleophiles is regio- and diastereoselective.
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access to optically active 3 substituted piperidines by ring expansion of Prolinols and derivatives
Chemistry: A European Journal, 2014Co-Authors: Domingo Gomez Pardo, Janine CossyAbstract:: The ring expansion of Prolinols via an aziridinium intermediate gives C3-substituted piperidines in good yields and enantiomeric excess, the substituent at the C3 position being derived from the most reactive nucleophile in the reaction mixture. Depending on the nucleophile, the reaction proceeds under thermodynamic or kinetic control. The regioselectivity of attack of nucleophiles on the aziridinium intermediate depends on the nature of the substituents on the nitrogen atom and the C4 position of the starting Prolinols.
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access to optically active 3 aminopiperidines by ring expansion of Prolinols thermodynamic versus kinetic control
European Journal of Organic Chemistry, 2012Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine CossyAbstract:3-Aminopiperidines are of great interest because they can possess a wide range of biological activity depending on the nitrogen substituents. Different approaches their synthesis are presented and the most efficient is a ring expansion of Prolinols induced by XtalFluor-E (diethylaminodifluorosulfinium tetrafluoroborate) in the presence of tetrabutylammonium azide, via an aziridinium intermediate, followed by the reduction of the corresponding azide. Under kinetic conditions, a 2-(azidomethyl)pyrrolidine/3-azidopiperidine ratio of 0:100 can be attained depending on the substituents present on the prolinol.
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access to optically active 3 azido and 3 aminopiperidine derivatives by enantioselective ring expansion of Prolinols
Organic Letters, 2011Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine CossyAbstract:The activation of N-alkyl Prolinols by XtalFluor E allowed the formation of an aziridinium intermediate that can react with tetrabutylammonium azide (nBu4NN3) to produce 3-azidopiperidines and/or 2-(azidomethyl)pyrrolidines, in a ratio up to 100/0. These 3-azidopiperidines can be reduced to the corresponding 3-aminopiperidines.
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enantioselective ring expansionof Prolinols an efficient and short synthesis of 2 phenylpiperidin 3 olderivatives and 3 hydroxypipecolic acids
Synlett, 2009Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine Cossy, Benjamin Burger, Cristina Navarro, Yang Zhao, Theodore CohenAbstract:A very short route to 2-phenylpiperidin-3-ol derivatives and 3-hydroxypipecolic acids is described. The approach uses two key steps: a one-pot reduction/Grignard addition sequence applied to alkyl proline esters and a ring expansion applied to the corresponding Prolinols.
Ingrid Dechamps - One of the best experts on this subject based on the ideXlab platform.
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Enantioselective ring expansion of prolinol derivatives. Two formal syntheses of (−)-swainsonine
Tetrahedron, 2007Co-Authors: Ingrid Dechamps, Domingo Gomez Pardo, Janine CossyAbstract:Abstract Two enantioselective formal syntheses of (−)-swainsonine have been achieved from l -proline by using an enantioselective ring enlargement of substituted Prolinols as the key step. The more efficient synthesis has been achieved in 14 steps with an overall yield of 14%.
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ring expansion induced by dast synthesis of substituted 3 fluoropiperidines from Prolinols and 3 fluoroazepanes from 2 hydroxymethylpiperidines
European Journal of Organic Chemistry, 2007Co-Authors: Ingrid Dechamps, Domingo Gomez Pardo, Janine CossyAbstract:Optically active Prolinols can be converted into optically active 3-fluoropiperidines by treatment with DAST. The reaction often produces 2-fluoromethylpyrrolidines as byproducts. The ring expansion was also applied to 2-hydroxypiperidines to produce 3-fluoroazepanes. The rearrangement proceeds via an aziridinium intermediate. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
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synthesis of optically active substituted 3 fluoropiperidines from Prolinols by using dast
Synlett, 2007Co-Authors: Ingrid Dechamps, Domingo Gomez Pardo, Janine CossyAbstract:The treatment of optically active Prolinols with DAST produces optically active 3-fluoropiperidines via aziridinium intermediates.
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enantioselective ring expansion of Prolinols and ring closing metathesis formal synthesis of swainsonine
Arkivoc, 2006Co-Authors: Ingrid Dechamps, Domingo Gomez Pardo, Janine CossyAbstract:An efficient enantioselective formal synthesis of (−)-swainsonine has been achieved in 14 steps with 14% global yield using an enantioselective ring enlargement of a substituted prolinol and a ring-closing metathesis as the key steps.
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Enantioselective ring expansion of Prolinols and ring-closing metathesis: formal synthesis of (−)-swainsonine
Arkivoc, 2006Co-Authors: Ingrid Dechamps, Domingo Gomez Pardo, Janine CossyAbstract:An efficient enantioselective formal synthesis of (−)-swainsonine has been achieved in 14 steps with 14% global yield using an enantioselective ring enlargement of a substituted prolinol and a ring-closing metathesis as the key steps.
Anne Cochi - One of the best experts on this subject based on the ideXlab platform.
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access to optically active 3 aminopiperidines by ring expansion of Prolinols thermodynamic versus kinetic control
European Journal of Organic Chemistry, 2012Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine CossyAbstract:3-Aminopiperidines are of great interest because they can possess a wide range of biological activity depending on the nitrogen substituents. Different approaches their synthesis are presented and the most efficient is a ring expansion of Prolinols induced by XtalFluor-E (diethylaminodifluorosulfinium tetrafluoroborate) in the presence of tetrabutylammonium azide, via an aziridinium intermediate, followed by the reduction of the corresponding azide. Under kinetic conditions, a 2-(azidomethyl)pyrrolidine/3-azidopiperidine ratio of 0:100 can be attained depending on the substituents present on the prolinol.
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access to optically active 3 azido and 3 aminopiperidine derivatives by enantioselective ring expansion of Prolinols
Organic Letters, 2011Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine CossyAbstract:The activation of N-alkyl Prolinols by XtalFluor E allowed the formation of an aziridinium intermediate that can react with tetrabutylammonium azide (nBu4NN3) to produce 3-azidopiperidines and/or 2-(azidomethyl)pyrrolidines, in a ratio up to 100/0. These 3-azidopiperidines can be reduced to the corresponding 3-aminopiperidines.
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enantioselective ring expansionof Prolinols an efficient and short synthesis of 2 phenylpiperidin 3 olderivatives and 3 hydroxypipecolic acids
Synlett, 2009Co-Authors: Anne Cochi, Domingo Gomez Pardo, Janine Cossy, Benjamin Burger, Cristina Navarro, Yang Zhao, Theodore CohenAbstract:A very short route to 2-phenylpiperidin-3-ol derivatives and 3-hydroxypipecolic acids is described. The approach uses two key steps: a one-pot reduction/Grignard addition sequence applied to alkyl proline esters and a ring expansion applied to the corresponding Prolinols.
Bei Zhao - One of the best experts on this subject based on the ideXlab platform.
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enantioselective reduction of ketones catalyzed by rare earth metals complexed with phenoxy modified chiral Prolinols
Journal of Organic Chemistry, 2018Co-Authors: Peng Song, Chengrong Lu, Bei ZhaoAbstract:Enantioselective reduction of ketones and α,β-unsaturated ketones by pinacolborane (HBpin) has been well-established by using chiral rare-earth metal catalysts with phenoxy modified Prolinols. A number of highly optically active alcohols were obtained from reduction of simple ketones catalyzed by ytterbium complex 1 [L4Yb(L4H)] (H2L4 = (S)-2- tert-butyl-6-((2-(hydroxydiphenylmethyl)pyrrolidin-1-yl)methyl)phenol). Moreover, α,β-unsaturated ketones were selectively reduced to a wide range of chiral allylic alcohols with excellent yields, high enantioselectivity, and complete chemoselectivity, catalyzed by a single component chiral ytterbium complex 2 [L1Yb(L1H)] (H2L1 = (S)-2,4-di-tert-butyl-6-((2-(hydroxydiphenylmethyl)pyrrolidin-1-yl)methyl)phenol).
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highly enantioselective epoxidation of α β unsaturated ketones catalyzed by rare earth amides me3si 2n 3re μ cl li thf 3 with phenoxy functionalized chiral Prolinols
Organic Letters, 2015Co-Authors: Chao Zeng, Dan Yuan, Bei ZhaoAbstract:A simple and efficient catalytic enantioselective epoxidation of α,β-unsaturated ketones has been successfully developed, which was catalyzed by rare-earth metal amides [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 (RE = Yb (1), La (2), Sm (3), Y (4), Lu (5)) in the presence of phenoxy-functionalized chiral Prolinols at room temperature using tert-butylhydroperoxide (TBHP) as the oxidant. The combination of an Yb-based amide 1 and a chiral proligand (S)-2,4-di-tert-butyl-6-((2-(hydroxydiphenylmethyl)pyrrolidin-1-yl)methyl)phenol) performed very well, and both the yields and the enantiomeric excess of the chiral epoxides reached up to 99% and 99% ee.
