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Updated: Jul 8, 2026
06:46
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Zirconium-promoted epoxide rearrangement-alkynylation sequence
Brian J Albert1, Kazunori Koide
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
The Journal of Organic Chemistry
|January 9, 2008
Summary
This study introduces a novel method for synthesizing propargylic alcohols using epoxides and terminal alkynes. The new reaction proceeds via 1,2-shifts, offering a versatile approach for various functional groups.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
- Catalysis
Background:
- Terminal alkynes typically react with epoxides via S(N)2 mechanisms to yield homopropargylic alcohols.
- Existing methods often require harsh conditions or are limited in substrate scope.
Purpose of the Study:
- To develop a new synthetic route for propargylic alcohols from epoxides and terminal alkynes.
- To utilize cationic zirconium acetylides as key reactive intermediates.
Main Methods:
- Employing cationic zirconium acetylides generated under mild conditions.
- Utilizing silver nitrate for alkyne pre-activation.
- Investigating the reaction mechanism involving 1,2-shifts.
Main Results:
- Successful synthesis of propargylic alcohols from epoxides and diverse terminal alkynes.
- Demonstration of the method's tolerance to acid- and base-sensitive functional groups.
- The reaction proceeds efficiently with both electron-rich and electron-deficient alkynes.
Conclusions:
- A novel and mild synthetic strategy for propargylic alcohol synthesis has been established.
- The developed method offers broad applicability and functional group compatibility.
- Cationic zirconium acetylides are effective activators and nucleophiles in this transformation.
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