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Updated: Mar 23, 2026
Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Catalytic borylation of methane.
Kyle T Smith1, Simon Berritt1, Mariano González-Moreiras1
1Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104, USA.
Researchers achieved the iridium-catalyzed borylation of methane, a significant advancement in hydrocarbon functionalization. This breakthrough enables direct conversion of methane into valuable borylated products using bis(pinacolborane).
Area of Science:
- Organometallic Chemistry
- Catalysis
- Hydrocarbon Functionalization
Background:
- Catalytic borylation of hydrocarbons has advanced, but methane, the simplest alkane, remains unconverted.
- Direct functionalization of methane is a long-standing challenge in chemistry due to its inert C-H bonds.
Purpose of the Study:
- To develop the first catalytic method for the direct borylation of methane.
- To identify efficient iridium-based catalysts and optimize reaction conditions for methane borylation.
Main Methods:
- Iridium-catalyzed reaction using bis(pinacolborane) in cyclohexane.
- High-pressure and high-throughput experimental screening.
- Computational mechanistic studies to understand and improve catalysis.
Main Results:
- Identified phenanthroline-coordinated iridium complexes yielding trace borylated products.
- Optimized conditions (150°C, 3500 kPa) with phosphine-coordinated catalysts achieved ~52% yield.
- Achieved turnover numbers of 100 and improved selectivity for monoborylation.
Conclusions:
- Demonstrated the first successful iridium-catalyzed borylation of methane.
- The study provides a foundation for further development of methane functionalization catalysts.
- This work opens new avenues for utilizing methane as a C1 feedstock.
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