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Yu Tang - One of the best experts on this subject based on the ideXlab platform.
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synthesis of amido spiro 2 2 pentanes via simmons smith cyclopropanation of allenamides
Organic and Biomolecular Chemistry, 2009Co-Authors: Ting Lu, Ryuji Hayashi, Kyle A Dekorver, Andrew G Lohse, Zhenlei Song, Richard P Hsung, Yu TangAbstract:A detailed account of Simmons–Smith cyclopropanations of allenamides en route to amido-spiro[2.2]pentanes is described here. While the Diastereoselectivity was low when using unsubstituted allenamides, the reaction is overall efficient and general, representing the most direct synthesis of both chemically and biologically interesting amido-spiro[2.2]pentane systems. With α-substituted allenamides, while the Diastereoselectivity could be improved significantly based on a series of conformational analyses, both mono- and bis-cyclopropanation products were observed. Consequently, several structurally intriguing amido-methylene cyclopropanes could also be prepared.
John F Hartwig - One of the best experts on this subject based on the ideXlab platform.
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cation control of Diastereoselectivity in iridium catalyzed allylic substitutions formation of enantioenriched tertiary alcohols and thioethers by allylation of 5h oxazol 4 ones and 5h thiazol 4 ones
ChemInform, 2014Co-Authors: Wenyong Chen, John F HartwigAbstract:Enantioselective Ir-catalyzed allylation of substituted oxazolones occurs with high Diastereoselectivity by employing the corresponding zinc enolates.
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cation control of Diastereoselectivity in iridium catalyzed allylic substitutions formation of enantioenriched tertiary alcohols and thioethers by allylation of 5h oxazol 4 ones and 5h thiazol 4 ones
Journal of the American Chemical Society, 2014Co-Authors: Wenyong Chen, John F HartwigAbstract:We report highly diastereo- and enantioselective allylations of substituted 5H-oxazol-4-ones and 5H-thiazol-4-ones catalyzed by a metallacyclic iridium complex. Enantioselective Ir-catalyzed allylation of substituted 5H-oxazol-4-ones occurs with high Diastereoselectivity by employing the corresponding zinc enolates; enantioselective Ir-catalyzed allylation of substituted 5H-thiazol-4-ones occurs with the corresponding magnesium enolates with high Diastereoselectivity. The allylation of substituted 5H-oxazol-4-ones provides rapid access to enantioenriched tertiary α-hydroxy acid derivatives unavailable through Mo-catalyzed allylic substitution. The allylation of substituted 5H-thiazol-4-ones provides a novel method to synthesize enantioenriched tertiary thiols and thioethers. The observed cation effect implies a novel method to control the Diastereoselectivity in Ir-catalyzed allylic substitution.
Wenhao Hu - One of the best experts on this subject based on the ideXlab platform.
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a facile access to polyfunctional oxygen containing heterocycles via intramolecularly formed protic oxonium ylide trapping processes
ChemInform, 2014Co-Authors: Wenhao HuAbstract:Intramolecular trapping of oxonium ylides, generated by Cu-catalyzed decomposition of diazoesters (I), with electron-deficient aldehydes and isatins yields 3-substituted 1,4-dioxan-2-ones with high Diastereoselectivity.
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Diastereoselectivity switch in cooperatively catalyzed three component reactions of an aryldiazoacetate an alcohol and a β γ unsaturated α keto ester
ChemInform, 2011Co-Authors: Jingjing Ji, Liping Yang, Xia Zhang, Yu Qian, Jing Zhou, Wenhao HuAbstract:In the presence of Rh2(OAc)4/AgBF4 the title reaction provides the erythro products with high Diastereoselectivity.
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Diastereoselectivity switch in cooperatively catalyzed three component reactions of an aryldiazoacetate an alcohol and a β γ unsaturated α keto ester
Journal of Organic Chemistry, 2011Co-Authors: Jingjing Ji, Liping Yang, Xia Zhang, Yu Qian, Jing Zhou, Wenhao HuAbstract:A highly switchable,Diastereoselectivity-controlled, three-component reaction of aryldiazoacetate, alcohol,and β,γ-unsaturated α-keto esters has been achieved through a dual-metal cooperative catalysis strategy.
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Copper(II)-Catalyzed Highly Diastereoselective Three-Component Reactions of Aryl Diazoacetates with Alcohols and Chalcones: An Easy Access to Furan Derivatives.
ChemInform, 2010Co-Authors: Changwei Zhai, Liping Yang, Wenhao HuAbstract:The title reaction affords γ-hydroxy ketone derivatives (IV) in high yield with excellent Diastereoselectivity.
Ting Lu - One of the best experts on this subject based on the ideXlab platform.
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synthesis of amido spiro 2 2 pentanes via simmons smith cyclopropanation of allenamides
Organic and Biomolecular Chemistry, 2009Co-Authors: Ting Lu, Ryuji Hayashi, Kyle A Dekorver, Andrew G Lohse, Zhenlei Song, Richard P Hsung, Yu TangAbstract:A detailed account of Simmons–Smith cyclopropanations of allenamides en route to amido-spiro[2.2]pentanes is described here. While the Diastereoselectivity was low when using unsubstituted allenamides, the reaction is overall efficient and general, representing the most direct synthesis of both chemically and biologically interesting amido-spiro[2.2]pentane systems. With α-substituted allenamides, while the Diastereoselectivity could be improved significantly based on a series of conformational analyses, both mono- and bis-cyclopropanation products were observed. Consequently, several structurally intriguing amido-methylene cyclopropanes could also be prepared.
Wenyong Chen - One of the best experts on this subject based on the ideXlab platform.
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cation control of Diastereoselectivity in iridium catalyzed allylic substitutions formation of enantioenriched tertiary alcohols and thioethers by allylation of 5h oxazol 4 ones and 5h thiazol 4 ones
ChemInform, 2014Co-Authors: Wenyong Chen, John F HartwigAbstract:Enantioselective Ir-catalyzed allylation of substituted oxazolones occurs with high Diastereoselectivity by employing the corresponding zinc enolates.
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cation control of Diastereoselectivity in iridium catalyzed allylic substitutions formation of enantioenriched tertiary alcohols and thioethers by allylation of 5h oxazol 4 ones and 5h thiazol 4 ones
Journal of the American Chemical Society, 2014Co-Authors: Wenyong Chen, John F HartwigAbstract:We report highly diastereo- and enantioselective allylations of substituted 5H-oxazol-4-ones and 5H-thiazol-4-ones catalyzed by a metallacyclic iridium complex. Enantioselective Ir-catalyzed allylation of substituted 5H-oxazol-4-ones occurs with high Diastereoselectivity by employing the corresponding zinc enolates; enantioselective Ir-catalyzed allylation of substituted 5H-thiazol-4-ones occurs with the corresponding magnesium enolates with high Diastereoselectivity. The allylation of substituted 5H-oxazol-4-ones provides rapid access to enantioenriched tertiary α-hydroxy acid derivatives unavailable through Mo-catalyzed allylic substitution. The allylation of substituted 5H-thiazol-4-ones provides a novel method to synthesize enantioenriched tertiary thiols and thioethers. The observed cation effect implies a novel method to control the Diastereoselectivity in Ir-catalyzed allylic substitution.