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1,n-Bisborylalkanes via Radical Boron Migration
Dinghai Wang1, Christian Mück-Lichtenfeld1, Armido Studer1
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstraße 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|May 5, 2020
Summary
This study details radical boron migration in diboronate complexes, efficiently forming valuable 1,n-bisborylalkanes. These reactions enable new synthetic pathways for organoboron compounds.
Area of Science:
- Organometallic Chemistry
- Radical Chemistry
- Synthetic Organic Chemistry
Background:
- Diboronate complexes are key intermediates in organoboron chemistry.
- Developing efficient methods for synthesizing functionalized bisborylalkanes is crucial for organic synthesis.
Purpose of the Study:
- To systematically investigate radical boron migration in diboronate complexes.
- To establish synthetic routes to synthetically valuable 1,n-bisborylalkanes.
Main Methods:
- Generation of diboronate complexes from bis(pinacolato)diboron and alkyl Grignard reagents.
- Radical generation via intermolecular H-abstraction with trifluoromethyl radicals or alkene perfluoroalkyl radical addition.
- Analysis of boron migration products using experimental techniques and DFT calculations.
Main Results:
- Efficient radical 1,2- and 1,4-boron migrations were achieved, yielding geminal and 1,3-bisborylalkanes.
- 1,5-boron migration to form 1,4-bisborylalkanes was observed with lower efficiency.
- DFT calculations supported experimental findings and indicated feasibility of 1,3-boron migration.
Conclusions:
- Radical boron migration offers a versatile strategy for constructing 1,n-bisborylalkanes.
- The study expands the synthetic utility of diboronate complexes in radical chemistry.
- This work provides fundamental insights into boron migration mechanisms.
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