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Updated: Jan 18, 2026
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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
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Catalytic Asymmetric (ene-endo)-Carbonyl-Ene Type Cyclizations
Lixia Shi1, Nobuya Tsuji2, Chendan Zhu1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|September 10, 2025
Summary
Researchers developed a new catalytic method for synthesizing homoallylic alcohols. This efficient asymmetric cyclization of alkenyl aldehydes offers a valuable tool for organic synthesis.
Area of Science:
- Organic Chemistry
- Catalysis
- Asymmetric Synthesis
Background:
- Carbonyl-ene reactions are atom-economical routes to homoallylic alcohols.
- Existing catalytic asymmetric intermolecular carbonyl-ene reactions are limited to activated substrates.
- Intramolecular asymmetric (ene-exo)-carbonyl-ene cyclizations are mature, but (ene-endo)-cyclizations are underdeveloped.
Purpose of the Study:
- To develop an efficient and enantioselective catalytic asymmetric (ene-endo)-carbonyl-ene cyclization for unbiased alkenyl aldehydes.
- To address the underdeveloped nature of (ene-endo)-carbonyl-ene cyclizations in chemical synthesis.
Main Methods:
- Utilized a strong and confined diarylprolinol silyl ether (IDPi) Brønsted acid catalyst.
- Investigated the regio- and enantioselective cyclization of various unbiased alkenyl aldehydes.
Main Results:
- Achieved efficient regio- and enantioselective catalytic asymmetric (ene-endo)-carbonyl-ene cyclization.
- Obtained high enantioselectivities, up to 98:2 e.r. (enantiomeric ratio).
- Demonstrated the method's utility for a range of homoallylic alcohol products.
Conclusions:
- The developed IDPi Brønsted acid catalyzed method is effective for (ene-endo)-carbonyl-ene cyclizations.
- This provides a new synthetic pathway to valuable homoallylic alcohols with high stereocontrol.
- The methodology expands the scope of asymmetric carbonyl-ene reactions.
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