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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
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Asymmetric Ruthenium-Catalyzed C-H Activation by a Versatile Chiral-Amide-Directing Strategy
Wenkun Chen1, Jijun Jiang1, Jun Wang1
1School of Chemistry, Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, Sun Yat-Sen University, 510006, Guangzhou, P. R. China.
Angewandte Chemie (International Ed. in English)
|December 16, 2023
Summary
A new chiral amide directing group enables ruthenium-catalyzed asymmetric C-H activation. This method efficiently synthesizes diverse chiral molecules, including natural products, with high stereoselectivity.
Area of Science:
- Organic Chemistry
- Catalysis
- Asymmetric Synthesis
Background:
- Chiral molecules are crucial in pharmaceuticals and natural products.
- Asymmetric C-H activation offers a direct route to chiral compounds.
- Developing versatile directing groups is key for efficient asymmetric catalysis.
Purpose of the Study:
- To develop a novel chiral amide directing group for ruthenium(II)-catalyzed asymmetric C-H activation.
- To explore the scope and limitations of this new methodology.
- To demonstrate the utility of the method in synthesizing complex chiral molecules.
Main Methods:
- Ruthenium(II)-catalyzed asymmetric C-H activation using a chiral amide directing group.
- Reactions with various olefins, aldehydes, and propargylic alcohols.
- Stereoselective synthesis of target chiral products.
Main Results:
- High stereoselectivities achieved for multiple chiral products, including 3,4-dihydroisocoumarins (up to 96% ee), isocoumarins (up to 92% ee), and phthalides (up to 99% ee).
- Efficient synthesis of chiral bicyclo[2.2.1]heptanes and allenes with high diastereoselectivity.
- Concise synthesis of biologically active compounds and natural products, such as Montroumarin and Cyclosporone E.
Conclusions:
- A versatile chiral amide directing group has been successfully developed.
- The methodology provides a powerful tool for asymmetric C-H activation.
- This approach enables efficient and stereoselective synthesis of valuable chiral molecules and natural products.
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