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Isolable diboryl radicals acting as highly efficient reaction intermediates under mild conditions
Rui Feng1, Wenbang Yang1, Wenqing Wang2
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China. gengwentan@nju.edu.cn xpwang@nju.edu.cn 544601409@qq.com.
Chemical Communications (Cambridge, England)
|October 1, 2019
Summary
Stable diboryl radicals were synthesized from diborane and dimesitylpyridylboranes. These radicals react with substrates to form boron reagents and improve catalytic reaction efficiency.
Area of Science:
- Organoboron Chemistry
- Radical Chemistry
- Catalysis
Background:
- Diborane compounds (B2(OR)4) are versatile precursors in synthetic chemistry.
- Dimesitylpyridylboranes serve as effective activators for B-B bond cleavage.
Purpose of the Study:
- To synthesize and characterize novel stable diboryl radicals.
- To explore the reactivity of these radicals with various substrates.
- To evaluate their utility in catalytic applications.
Main Methods:
- Synthesis of diboryl radicals 3 and 4.
- Characterization using single crystal X-ray crystallography, EPR, and UV/Vis spectroscopy.
- Theoretical calculations to understand radical properties.
- Reactivity studies with p-benzoquinone, TEMPO, and its derivatives.
Main Results:
- Stable diboryl radicals 3 and 4 were obtained in moderate yields.
- Characterization confirmed the structure and stability of the radicals.
- Diboryl radicals reacted with substrates to yield valuable boron-containing reagents.
- Catalytic reactions using diboryl radicals showed significantly higher yields compared to traditional catalysts.
Conclusions:
- The synthesized diboryl radicals are stable and synthetically useful.
- Their stability is crucial for enhancing efficiency in catalytic processes.
- This work introduces new boron-containing reagents and catalytic systems.
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