2-Isopropylbenzimidazole and 2-methylbenzimidazole as bulky proton sources

Stereoselective protonation and application to the synthesis of γ- and δ-lactones

Aakash Sengupta, Seijiro Hosokawa

    研究成果: Article

    1 引用 (Scopus)

    抄録

    2-Isopropylbenzimidazole and 2-methylbenzimidazole have been found to be effective bulky proton sources for stereoselective protonation of chiral enolate anions. 2-Isopropylbenzimidazole worked in the stereoselective protonation of the Birch reduction of chiral α,β-unsaturated imides. On the other hand, 2-methylbenzimidazole was found to be the best protonation reagent in the isomerization reaction of α,β-unsaturated imide into β,γ-unsaturated imide. The Birch reduction using 2-isopropylbenzimidazole realized a concise and stereoselective synthesis of δ-lactone 14, a sex pheromone of Macrocentrus grandii, while the isomerization reaction using 2-methylbenzimidazole was employed in the highly stereoselective synthesis of the γ-lactone intermediate in the synthesis of depsipeptide antibiotics. These bulky proton sources would be powerful tools to achieve a concise synthesis of natural products.

    元の言語English
    ページ(範囲)411-414
    ページ数4
    ジャーナルTetrahedron Letters
    60
    発行部数5
    DOI
    出版物ステータスPublished - 2019 1 31

    Fingerprint

    Imides
    Protonation
    Lactones
    Protons
    Betula
    Isomerization
    Depsipeptides
    Sex Attractants
    Biological Products
    Anions
    Anti-Bacterial Agents
    2-methylbenzimidazole

    ASJC Scopus subject areas

    • Biochemistry
    • Drug Discovery
    • Organic Chemistry

    これを引用

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    abstract = "2-Isopropylbenzimidazole and 2-methylbenzimidazole have been found to be effective bulky proton sources for stereoselective protonation of chiral enolate anions. 2-Isopropylbenzimidazole worked in the stereoselective protonation of the Birch reduction of chiral α,β-unsaturated imides. On the other hand, 2-methylbenzimidazole was found to be the best protonation reagent in the isomerization reaction of α,β-unsaturated imide into β,γ-unsaturated imide. The Birch reduction using 2-isopropylbenzimidazole realized a concise and stereoselective synthesis of δ-lactone 14, a sex pheromone of Macrocentrus grandii, while the isomerization reaction using 2-methylbenzimidazole was employed in the highly stereoselective synthesis of the γ-lactone intermediate in the synthesis of depsipeptide antibiotics. These bulky proton sources would be powerful tools to achieve a concise synthesis of natural products.",
    keywords = "Benzimidazole, Proton source, Stereoselective protonation, γ-Lactone, δ-Lactone",
    author = "Aakash Sengupta and Seijiro Hosokawa",
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    TY - JOUR

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    T2 - Stereoselective protonation and application to the synthesis of γ- and δ-lactones

    AU - Sengupta, Aakash

    AU - Hosokawa, Seijiro

    PY - 2019/1/31

    Y1 - 2019/1/31

    N2 - 2-Isopropylbenzimidazole and 2-methylbenzimidazole have been found to be effective bulky proton sources for stereoselective protonation of chiral enolate anions. 2-Isopropylbenzimidazole worked in the stereoselective protonation of the Birch reduction of chiral α,β-unsaturated imides. On the other hand, 2-methylbenzimidazole was found to be the best protonation reagent in the isomerization reaction of α,β-unsaturated imide into β,γ-unsaturated imide. The Birch reduction using 2-isopropylbenzimidazole realized a concise and stereoselective synthesis of δ-lactone 14, a sex pheromone of Macrocentrus grandii, while the isomerization reaction using 2-methylbenzimidazole was employed in the highly stereoselective synthesis of the γ-lactone intermediate in the synthesis of depsipeptide antibiotics. These bulky proton sources would be powerful tools to achieve a concise synthesis of natural products.

    AB - 2-Isopropylbenzimidazole and 2-methylbenzimidazole have been found to be effective bulky proton sources for stereoselective protonation of chiral enolate anions. 2-Isopropylbenzimidazole worked in the stereoselective protonation of the Birch reduction of chiral α,β-unsaturated imides. On the other hand, 2-methylbenzimidazole was found to be the best protonation reagent in the isomerization reaction of α,β-unsaturated imide into β,γ-unsaturated imide. The Birch reduction using 2-isopropylbenzimidazole realized a concise and stereoselective synthesis of δ-lactone 14, a sex pheromone of Macrocentrus grandii, while the isomerization reaction using 2-methylbenzimidazole was employed in the highly stereoselective synthesis of the γ-lactone intermediate in the synthesis of depsipeptide antibiotics. These bulky proton sources would be powerful tools to achieve a concise synthesis of natural products.

    KW - Benzimidazole

    KW - Proton source

    KW - Stereoselective protonation

    KW - γ-Lactone

    KW - δ-Lactone

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