Generating Fischer-Type Rh-Carbenes with Rh-Carbynoids
Eric Palomo1,2, Akhilesh K Sharma1, Zhaofeng Wang1
1Institute of Chemical Research of Catalonia (ICIQ-CERCA), The Barcelona Institute of Science and Technology, Països Catalans 16, 43007 Tarragona, Spain.
This study introduces the first catalytic method to generate rhodium(II)-carbenes from carboxylic acids. This breakthrough enables efficient synthesis of complex cyclopropyl-fused lactones with high stereocontrol.
Area of Science:
- Organometallic Chemistry
- Organic Synthesis
- Catalysis
Background:
- Rhodium(II)-carbenes are versatile intermediates in organic synthesis.
- Previous methods for generating these species have limitations.
Purpose of the Study:
- To develop a novel catalytic method for generating Fischer-type acyloxy Rh(II)-carbenes.
- To explore the synthetic utility of these intermediates in constructing complex molecules.
Main Methods:
- Catalytic generation of Rh(II)-carbenes from carboxylic acids and Rh(II)-carbynoids.
- Cyclopropanation reactions.
- Density Functional Theory (DFT) calculations.
Main Results:
- Successful catalytic generation of a novel class of transient donor/acceptor Rh(II)-carbenes.
- Access to densely functionalized cyclopropyl-fused lactones via cyclopropanation.
- Excellent diastereoselectivity achieved in the cyclopropanation process.
Conclusions:
- The developed method provides a new route to valuable lactone structures.
- DFT calculations elucidated the properties of key intermediates and the reaction mechanism.
- This work expands the toolkit for catalytic carbene transformations.
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