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Terminal C(sp3)-H borylation through intermolecular radical sampling
Miao Wang1, Yahao Huang1, Peng Hu1
1Institute of Green Chemistry and Molecular Engineering, Lehn Institute of Functional Materials, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China.
Science (New York, N.Y.)
|February 1, 2024
Summary
This study introduces a new photocatalytic method for selectively functionalizing terminal C(sp3)-H bonds in alkanes. The iron-catalyzed borylation process overcomes challenges in site-selective alkane transformations.
Area of Science:
- Organic Chemistry
- Catalysis
- Photochemistry
Background:
- Hydrogen atom transfer (HAT) is crucial for activating strong C(sp3)-H bonds in alkanes.
- Site-selective functionalization of unbranched alkanes remains challenging due to similar C(sp3)-H bond strengths.
Purpose of the Study:
- To develop a photocatalytic method for selective borylation of terminal C(sp3)-H bonds.
- To address the challenge of site-selectivity in alkane functionalization.
Main Methods:
- Iron-catalyzed intermolecular radical sampling.
- Photocatalysis.
- Mechanistic investigations.
Main Results:
- Achieved selective borylation of terminal C(sp3)-H bonds in unbranched alkanes.
- Demonstrated a reversible HAT process followed by selective carbon radical borylation.
- Identified a potential role for a boron-sulfoxide complex in achieving high regioselectivity.
Conclusions:
- The developed photocatalytic method offers a new route for selective alkane functionalization.
- The findings advance the field of C-H bond activation and functionalization.
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