Polycyclic Scaffolds through the Intermediacy of Boron-Stabilized Nonclassical Carbocations
Ling Cheng1, Mingkai Zhang1, James P Morken1
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States.
Journal of the American Chemical Society
|November 7, 2025
Summary
Boron-containing norbornenes rearrange into nortricyclanes with Brønsted acid catalysis. This study explores the boron substituent
Area of Science:
- Organic Chemistry
- Organoboron Chemistry
Background:
- Norbornene derivatives are versatile synthetic platforms.
- Boron substituents can influence carbocation stability and reactivity.
Purpose of the Study:
- Investigate the regioselective rearrangement of boron-containing norbornenes.
- Elucidate the role of boron in stabilizing carbocation intermediates.
- Develop synthetic routes to multisubstituted tricyclic compounds.
Main Methods:
- Catalysis with Brønsted acids.
- Experimental studies.
- Computational chemistry (e.g., DFT).
Main Results:
- Regioselective rearrangement of boron-containing norbornenes to nortricyclanes.
- Evidence for unique stabilization of the 2-norbornyl cation by boron.
- Demonstration of selective functionalization of the boronic ester product.
Conclusions:
- Boron substituents significantly impact norbornene rearrangement pathways.
- The developed methodology provides access to diverse tricyclic structures.
- Potential for broad applications in synthetic chemistry.
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