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Jun-ichi Nishimura - One of the best experts on this subject based on the ideXlab platform.
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Ytterbium Triflate‐Catalyzed Asymmetric Hetero Diels‐Alder Cycloaddition of a 1‐Thiabuta‐1,3‐diene with a Chiral N‐ Acryloyloxazolidinone Dienophile. Diastereoface Control by Solvents or Achiral Additives.
ChemInform, 2010Co-Authors: Takao Saito, Mikako Kawamura, Jun-ichi NishimuraAbstract:Abstract Ytterbium triflate [Yb(OTf) 3 ]-catalyzed asymmetric Hetero Diels-Alder Cycloaddition reaction of 2,4-diphenyl-1-thiabuta-1,3-diene with ( S )- N -acryloyl-4-benzyl-1,3-oxazolidin-2-one is described in which the sense of the π-facial selectivity can be controlled by solvents or additives employed without altering the auxiliary chirality for the asymmetric induction.
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Lewis acid-catalyzed asymmetric Hetero Diels-Alder Cycloaddition of a 1-Thiabuta-1,3-diene with Chiral N-Acryloyl- and N-Crotonoyl-oxazolidinone dienophiles
Tetrahedron Letters, 1997Co-Authors: Takao Saito, Hirofumi Suda, Mikako Kawamura, Jun-ichi Nishimura, Akemi YamayaAbstract:Abstract Me 2 AlCl- and TiCl 4 -catalyzed asymmetric Hetero Diels-Alder Cycloaddition reactions of 2,4-diphenyl-1-thiabuta-1,3-diene with ( S )- N -acryloyl- and ( S )- N -crotonoyl-4-benzyl-1,3-oxazolidin-2-one dienophiles are described in which not only the sense of the π-facial selectivity but also the degree dramatically varied as a function of stoichiometry of the added Lewis acids.
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Ytterbium triflate-catalyzed asymmetric Hetero Diels-Alder Cycloaddition of a 1-thiabuta-1,3-diene with a chiral N-acryloyloxazolidinone dienophile. Diastereoface control by solvents or achiral additives
Tetrahedron Letters, 1997Co-Authors: Takao Saito, Mikako Kawamura, Jun-ichi NishimuraAbstract:Abstract Ytterbium triflate [Yb(OTf) 3 ]-catalyzed asymmetric Hetero Diels-Alder Cycloaddition reaction of 2,4-diphenyl-1-thiabuta-1,3-diene with ( S )- N -acryloyl-4-benzyl-1,3-oxazolidin-2-one is described in which the sense of the π-facial selectivity can be controlled by solvents or additives employed without altering the auxiliary chirality for the asymmetric induction.
Zhixiang Xie - One of the best experts on this subject based on the ideXlab platform.
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Biomimetic Total Synthesis of Paeoveitol
Organic letters, 2016Co-Authors: Yuhan Zhang, Yonghong Guo, Zhixiang XieAbstract:A highly stereocontrolled synthesis of paeoveitol has been developed in 26% yield, in 7 steps from commercially available materials. The synthetic strategy was inspired primarily by the biogenetic hypothesis and was enabled by Hetero-Diels–Alder Cycloaddition to construct the target molecular framework.
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Total syntheses of (-)-spirooliganones A and B.
Organic letters, 2014Co-Authors: Lin Wei, Mingxing Xiao, Zhixiang XieAbstract:The enantioselective syntheses of (-)-spirooliganones A and B have been accomplished in eight steps from commercially available starting materials. Noteworthy transformations include a three-component Hetero-Diels-Alder Cycloaddition to construct the tetracyclic core of spirooliganones, a Sharpless asymmetric dihydroxylation, and a tandem oxidative dearomatization/cyclization to build the oxa-spiro cyclohexadienone skeleton. The straightforward syntheses were performed without protecting groups.
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Total Syntheses of (−)-Spirooliganones A and B
2014Co-Authors: Lin Wei, Mingxing Xiao, Zhixiang XieAbstract:The enantioselective syntheses of (−)-spirooliganones A and B have been accomplished in eight steps from commercially available starting materials. Noteworthy transformations include a three-component Hetero-Diels–Alder Cycloaddition to construct the tetracyclic core of spirooliganones, a Sharpless asymmetric dihydroxylation, and a tandem oxidative dearomatization/cyclization to build the oxa-spiro cyclohexadienone skeleton. The straightforward syntheses were performed without protecting groups
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Expeditious Synthesis of the Aromatic Spiroketal Skeleton Using Hetero‐Diels—Alder Cycloaddition.
ChemInform, 2006Co-Authors: Guanglian Zhou, Deping Zheng, Zhixiang XieAbstract:Abstract The Hetero-Diels–Alder reactions of enolic ethers generated from methylenation of various esters are described, which allow for the rapid synthesis of various substituted [6,6] aromatic spiroketal skeletons.
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expeditious synthesis of the aromatic spiroketal skeleton using Hetero diels alder Cycloaddition
Tetrahedron Letters, 2006Co-Authors: Guanglian Zhou, Deping Zheng, Zhixiang XieAbstract:Abstract The Hetero-Diels–Alder reactions of enolic ethers generated from methylenation of various esters are described, which allow for the rapid synthesis of various substituted [6,6] aromatic spiroketal skeletons.
Takao Saito - One of the best experts on this subject based on the ideXlab platform.
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Ytterbium Triflate‐Catalyzed Asymmetric Hetero Diels‐Alder Cycloaddition of a 1‐Thiabuta‐1,3‐diene with a Chiral N‐ Acryloyloxazolidinone Dienophile. Diastereoface Control by Solvents or Achiral Additives.
ChemInform, 2010Co-Authors: Takao Saito, Mikako Kawamura, Jun-ichi NishimuraAbstract:Abstract Ytterbium triflate [Yb(OTf) 3 ]-catalyzed asymmetric Hetero Diels-Alder Cycloaddition reaction of 2,4-diphenyl-1-thiabuta-1,3-diene with ( S )- N -acryloyl-4-benzyl-1,3-oxazolidin-2-one is described in which the sense of the π-facial selectivity can be controlled by solvents or additives employed without altering the auxiliary chirality for the asymmetric induction.
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Lewis acid-catalyzed asymmetric Hetero Diels-Alder Cycloaddition of a 1-Thiabuta-1,3-diene with Chiral N-Acryloyl- and N-Crotonoyl-oxazolidinone dienophiles
Tetrahedron Letters, 1997Co-Authors: Takao Saito, Hirofumi Suda, Mikako Kawamura, Jun-ichi Nishimura, Akemi YamayaAbstract:Abstract Me 2 AlCl- and TiCl 4 -catalyzed asymmetric Hetero Diels-Alder Cycloaddition reactions of 2,4-diphenyl-1-thiabuta-1,3-diene with ( S )- N -acryloyl- and ( S )- N -crotonoyl-4-benzyl-1,3-oxazolidin-2-one dienophiles are described in which not only the sense of the π-facial selectivity but also the degree dramatically varied as a function of stoichiometry of the added Lewis acids.
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Ytterbium triflate-catalyzed asymmetric Hetero Diels-Alder Cycloaddition of a 1-thiabuta-1,3-diene with a chiral N-acryloyloxazolidinone dienophile. Diastereoface control by solvents or achiral additives
Tetrahedron Letters, 1997Co-Authors: Takao Saito, Mikako Kawamura, Jun-ichi NishimuraAbstract:Abstract Ytterbium triflate [Yb(OTf) 3 ]-catalyzed asymmetric Hetero Diels-Alder Cycloaddition reaction of 2,4-diphenyl-1-thiabuta-1,3-diene with ( S )- N -acryloyl-4-benzyl-1,3-oxazolidin-2-one is described in which the sense of the π-facial selectivity can be controlled by solvents or additives employed without altering the auxiliary chirality for the asymmetric induction.
Niru B. Soni - One of the best experts on this subject based on the ideXlab platform.
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An Unusual Intramolecular Hetero-Diels−Alder Cycloaddition
Journal of Organic Chemistry, 2005Co-Authors: Eric J. Stoner, Alan C. Christesen, Rodger F. Henry, L. Steven Hollis, Robert F. Keyes, Ian Marsden, Tamara C. Rehm, Sandeep G. Shiroor, Michael S. Allen, Niru B. SoniAbstract:A new reaction of erythronolides, an intramolecular Hetero-Diels−Alder, has been discovered. Heated aqueous alcoholic solutions of ABT-773 (1) and its cis isomer (3) convert slowly to cycloadducts 2 and 4, respectively. Optimal reaction conditions, mechanistic studies supported by molecular modeling, and biological activity data are reported. Single-crystal X-ray structures for both adducts 2 and 4 have been obtained.
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An unusual intramolecular Hetero-Diels-Alder Cycloaddition.
The Journal of organic chemistry, 2005Co-Authors: Eric J. Stoner, Alan C. Christesen, Rodger F. Henry, L. Steven Hollis, Robert F. Keyes, Ian Marsden, Tamara C. Rehm, Sandeep G. Shiroor, Michael S. Allen, Niru B. SoniAbstract:A new reaction of erythronolides, an intramolecular Hetero-Diels-Alder, has been discovered. Heated aqueous alcoholic solutions of ABT-773 (1) and its cis isomer (3) convert slowly to cycloadducts 2 and 4, respectively. Optimal reaction conditions, mechanistic studies supported by molecular modeling, and biological activity data are reported. Single-crystal X-ray structures for both adducts 2 and 4 have been obtained.
Andrew J. P. White - One of the best experts on this subject based on the ideXlab platform.
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Stereoselective Synthesis of cis‐ and trans‐2,3‐Disubstituted Tetrahydrofurans via Oxonium—Prins Cyclization: Access to the Cordigol Ring System.
ChemInform, 2010Co-Authors: Alston C Spivey, Luca Laraia, Andrew R Bayly, Henry S. Rzepa, Andrew J. P. WhiteAbstract:SnBr4-promoted oxonium−Prins cyclizations to form 2,3-disubstituted tetrahydrofurans (THFs) are reported. In the absence of an internal nucleophile, the carbocation intermediates are trapped by bromide to give 2,3-cis- and 2,3-trans-configured products; two variations with intramolecular trapping are also reported. One of these allows a single-step stereocontrolled synthesis of the core 2,3-cis-THF ring system of cordigol, a fungicidal polyphenol from the stem bark of Cordia goetzei. For this latter transformation, a stepwise oxonium−Prins/cation trapping pathway rather than orthoquinonemethide formation/Hetero-Diels−Alder Cycloaddition is supported computationally.
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stereoselective synthesis of cis and trans 2 3 disubstituted tetrahydrofurans via oxonium prins cyclization access to the cordigol ring system
Organic Letters, 2010Co-Authors: Alston C Spivey, Luca Laraia, Andrew R Bayly, Henry S. Rzepa, Andrew J. P. WhiteAbstract:SnBr4-promoted oxonium−Prins cyclizations to form 2,3-disubstituted tetrahydrofurans (THFs) are reported. In the absence of an internal nucleophile, the carbocation intermediates are trapped by bromide to give 2,3-cis- and 2,3-trans-configured products; two variations with intramolecular trapping are also reported. One of these allows a single-step stereocontrolled synthesis of the core 2,3-cis-THF ring system of cordigol, a fungicidal polyphenol from the stem bark of Cordia goetzei. For this latter transformation, a stepwise oxonium−Prins/cation trapping pathway rather than orthoquinonemethide formation/Hetero-Diels−Alder Cycloaddition is supported computationally.
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Stereoselective Synthesis of cis- and trans-2,3-Disubstituted Tetrahydrofurans via Oxonium−Prins Cyclization: Access to the Cordigol Ring System
Organic letters, 2010Co-Authors: Alston C Spivey, Luca Laraia, Andrew R Bayly, Henry S. Rzepa, Andrew J. P. WhiteAbstract:SnBr4-promoted oxonium−Prins cyclizations to form 2,3-disubstituted tetrahydrofurans (THFs) are reported. In the absence of an internal nucleophile, the carbocation intermediates are trapped by bromide to give 2,3-cis- and 2,3-trans-configured products; two variations with intramolecular trapping are also reported. One of these allows a single-step stereocontrolled synthesis of the core 2,3-cis-THF ring system of cordigol, a fungicidal polyphenol from the stem bark of Cordia goetzei. For this latter transformation, a stepwise oxonium−Prins/cation trapping pathway rather than orthoquinonemethide formation/Hetero-Diels−Alder Cycloaddition is supported computationally.