Organocatalytic Enantioselective Vinylcyclopropane-Cyclopentene (VCP-CP) Rearrangement
Gorka Garay1, Josebe Hurtado1, Manuel Pedrón2
1Department of Organic and Inorganic Chemistry, University of the Basque Country (UPV/EHU), P.O. Box 644, 48080, Bilbao, Spain.
Angewandte Chemie (International Ed. in English)
|April 12, 2023
Summary
This study shows a new catalytic method for vinylcyclopropane rearrangement using enamine intermediates. The process effectively transfers chirality from the catalyst to create stereocontrolled cyclopentene products from racemic starting materials.
Area of Science:
- Organic Chemistry
- Catalysis
- Stereoselective Synthesis
Background:
- Vinylcyclopropane rearrangements are valuable synthetic transformations.
- Enantioselective catalysis is crucial for producing chiral molecules.
- Previous methods may have limitations in substrate scope or stereocontrol.
Purpose of the Study:
- To develop a catalytic and enantioselective vinylcyclopropane-cyclopentene rearrangement.
- To utilize enamine intermediates for activating (vinylcyclopropyl)acetaldehydes.
- To achieve high stereocontrol in the formation of cyclopentene products.
Main Methods:
- Employing a catalytic system for vinylcyclopropane rearrangement.
- Activation of racemic (vinylcyclopropyl)acetaldehydes via enamine intermediates.
- Utilizing donor-acceptor cyclopropane intermediates for ring opening.
Main Results:
- Successful catalytic and enantioselective vinylcyclopropane-cyclopentene rearrangement.
- Generation of an acyclic iminium ion/dienolate intermediate from racemic starting materials.
- High effectiveness of chirality transfer from the catalyst to the final product.
Conclusions:
- The developed method enables stereocontrolled synthesis of diverse cyclopentenes.
- Enamine activation provides an efficient route for this rearrangement.
- This approach offers a powerful tool for asymmetric synthesis.
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