Palladium-catalyzed solid-state borylation of aryl halides using mechanochemistry.
Koji Kubota1,2, Emiru Baba1, Tamae Seo1
1Division of Applied Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
Beilstein Journal of Organic Chemistry
|August 12, 2022
Summary
This study introduces a fast, solvent-free palladium-catalyzed cross-coupling reaction using ball milling. The method efficiently produces arylboronates in air, offering a greener alternative for organic synthesis.
Area of Science:
- Organic Chemistry
- Green Chemistry
- Materials Science
Background:
- Palladium-catalyzed cross-coupling reactions are vital in organic synthesis.
- Traditional methods often require harsh conditions, excess solvents, and inert atmospheres.
- Developing sustainable and efficient synthetic methodologies is a key challenge.
Purpose of the Study:
- To develop a solvent-free, solid-state palladium-catalyzed borylation reaction.
- To utilize mechanochemistry (ball milling) for efficient cross-coupling.
- To provide a greener and faster route to synthetically useful arylboronates.
Main Methods:
- Solid-state palladium-catalyzed cross-coupling using ball milling.
- Reaction of aryl halides with bis(pinacolato)diboron.
- Optimization of reaction time and conditions for mechanochemical synthesis.
Main Results:
- High yields of various arylboronates achieved within 10 minutes for most substrates.
- Successful execution of reactions under ambient air conditions.
- Demonstration of gram-scale synthesis under solvent-free, mechanochemical conditions.
Conclusions:
- Ball milling provides an efficient platform for solid-state palladium-catalyzed borylation.
- The developed method offers a sustainable, rapid, and solvent-minimized approach to arylboronates.
- This technique is suitable for large-scale synthesis and reduces reliance on traditional organic solvents.
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