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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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Myoglobin-Catalyzed Olefination of Aldehydes
1Department of Chemistry, University of Rochester, 120 Trustee Road, Rochester, NY, 14627, USA.
Angewandte Chemie (International Ed. in English)
|January 15, 2016
Summary
Engineered myoglobin variants catalyze aldehyde olefination, a key reaction for creating carbon-carbon double bonds. This biocatalytic method offers high efficiency and diastereoselectivity, expanding synthetic possibilities.
Area of Science:
- Organic Chemistry
- Biocatalysis
- Protein Engineering
Background:
- Aldehyde olefination is crucial for synthesizing carbon-carbon double bonds.
- Existing methods lack biocatalytic options for this transformation.
Purpose of the Study:
- To develop the first biocatalyst for aldehyde olefination.
- To engineer myoglobin variants for efficient olefination reactions.
Main Methods:
- Protein engineering of myoglobin variants.
- Catalysis of aldehyde olefination using α-diazoesters.
- Assessing catalytic efficiency and diastereoselectivity.
Main Results:
- Engineered myoglobin variants achieved high catalytic efficiency (up to 4,900 turnovers).
- Excellent E-diastereoselectivity (92-99.9% de) was observed.
- The method demonstrated broad substrate scope with various aldehydes and diazoacetates.
Conclusions:
- This study presents the first biocatalytic approach to aldehyde olefination.
- Metalloprotein-based catalysts are versatile for valuable chemical transformations.
- Engineered myoglobin expands the toolkit for organic synthesis.
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