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A general method for Suzuki-Miyaura coupling reactions using lithium triisopropyl borates
Matthias A Oberli1, Stephen L Buchwald
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Organic Letters
|August 17, 2012
Summary
Lithium triisopropyl borates offer a stable alternative for Suzuki-Miyaura coupling reactions. A new one-pot procedure enables efficient coupling of heterocycles with aryl halides.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Suzuki-Miyaura coupling is a vital carbon-carbon bond-forming reaction.
- Boronic acids, commonly used in this coupling, are susceptible to protodeboronation.
- Development of more stable boron reagents is crucial for synthetic efficiency.
Purpose of the Study:
- To report conditions for Suzuki-Miyaura coupling using lithium triisopropyl borates.
- To develop a one-pot procedure for lithiation, borylation, and Suzuki-Miyaura coupling.
- To demonstrate the stability and utility of these borate species.
Main Methods:
- Investigated Suzuki-Miyaura coupling conditions with lithium triisopropyl borates.
- Developed a sequential one-pot reaction involving lithiation and borylation.
- Coupled various heterocycles with aryl halides using the developed methodology.
Main Results:
- Established effective conditions for Suzuki-Miyaura coupling of lithium triisopropyl borates.
- Demonstrated a convenient one-pot procedure for synthesizing coupled products.
- Showcased the enhanced stability of borate species against protodeboronation compared to boronic acids.
Conclusions:
- Lithium triisopropyl borates are stable and effective reagents for Suzuki-Miyaura coupling.
- The one-pot procedure offers a streamlined approach for synthesizing diverse coupled products.
- These findings provide a practical advancement in cross-coupling methodologies.
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