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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
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Merging Ketyl Radical Chemistry and Allylboration via Strain Release: One-Pot Multicomponent Access to Sterically
Aiswarya Mini1, Het Vyas1, Ashvin J Gangani1
1Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey 07030, United States.
Organic Letters
|March 18, 2025
Summary
We developed a novel one-pot reaction for synthesizing functionalized cyclopentenes using diboryl-activated cyclopropyl ketones. This method efficiently creates complex molecules with multiple stereocenters and useful functional groups.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Ketyl radical-mediated reactions of cyclopropyl ketones (CPKs) typically yield cyclopentenes with limited stereochemical complexity.
- Existing methods require specific activating groups and result in non-adjacent stereocenters.
Purpose of the Study:
- To develop a new synthetic strategy for accessing densely functionalized cyclopentenes.
- To merge ketyl radical chemistry with allylboration for enhanced molecular complexity.
Main Methods:
- A one-pot multicomponent reaction involving diboryl-activated CPKs, alkynes, and aldehydes.
- Utilized ketyl radical generation and subsequent allylboration.
Main Results:
- Achieved highly diastereoselective synthesis of functionalized cyclopentenes.
- Introduced homoallylic alcohol, ketone, and alkenyl boronate motifs on adjacent stereogenic centers.
- Synthesized rare ketone-functionalized γ,γ-disubstituted allylic diborons.
Conclusions:
- The developed method provides efficient access to complex cyclopentene structures.
- Demonstrated the utility of diboryl-activated CPKs in multicomponent reactions.
- Expanded the scope of ketyl radical chemistry and allylboration.
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