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Carbonylative C-C Bond Activation of Aminocyclopropanes Using a Temporary Directing Group Strategy
Gang-Wei Wang1, Olga O Sokolova1, Tom A Young2
1School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|October 30, 2020
Summary
This study introduces a novel method for activating cyclopropane carbon-carbon bonds using temporary directing groups (TDGs). The approach utilizes an isocyanate-derived TDG and a unique ring contraction process for controlled bond activation.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Temporary directing groups (TDGs) are crucial for C-C bond activation strategies.
- Regiocontrolled activation of cyclopropane C-C bonds using TDGs remains an underdeveloped area in synthetic chemistry.
Purpose of the Study:
- To develop a novel TDG-based methodology for the regiocontrolled carbonylative C-C bond activation of cyclopropanes.
- To explore an unusual ring contraction process for facilitating this activation.
Main Methods:
- Transient installation of an isocyanate-derived temporary directing group (TDG).
- Utilizing a unique ring contraction process to enable C-C bond activation.
- Application in carbonylative coupling reactions of cyclopropanes.
Main Results:
- Demonstrated successful regiocontrolled C-C bond activation of cyclopropanes.
- The novel isocyanate-derived TDG approach bypasses the need for traditional carbonyl condensation events.
- The ring contraction process is key to the observed reactivity.
Conclusions:
- A new TDG-based strategy for carbonylative C-C bond activation of cyclopropanes has been established.
- This method offers an alternative to existing TDG-enabled C-C bond activation techniques.
- The findings expand the scope of TDG applications in organic synthesis.
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