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A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
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RhIII-Catalyzed Direct Heteroarylation of Unactivated C(sp3)-H with N-Heteroaryl Boronates
Rong Chi1, Guang-Yu Xu1, Zhen-Ang Liu1
1Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252000, China.
The Journal of Organic Chemistry
|April 30, 2024
Summary
This study introduces a rhodium(III)-catalyzed reaction for direct heteroarylation of aliphatic C(sp3)-H bonds in 2-alkylpyridines. The method efficiently creates new carbon-heteroaryl bonds using various heterocyclic boronates.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Direct C-H functionalization is a key strategy in modern organic synthesis.
- Aliphatic C(sp3)-H bonds are challenging substrates for direct functionalization.
- Developing efficient methods for C(sp3)-heteroaryl bond formation is highly desirable.
Purpose of the Study:
- To develop a rhodium(III)-catalyzed direct heteroarylation of unactivated aliphatic C(sp3)-H bonds.
- To explore the scope and limitations of this new catalytic protocol.
Main Methods:
- Rhodium(III)-catalyzed direct heteroarylation reaction.
- Utilized unactivated aliphatic C(sp3)-H bonds in 2-alkylpyridines.
- Employed various heteroaryl organoboron reagents.
Main Results:
- Successful direct heteroarylation of 2-alkylpyridines with diverse heteroaryl boronates.
- Demonstrated compatibility with pyridine, pyrazole, furan, and quinoline containing boronates.
- Established an efficient route for constructing C(sp3)-heteroaryl bonds.
Conclusions:
- The developed rhodium(III)-catalyzed method provides an efficient pathway for C(sp3)-heteroaryl bond formation.
- This methodology expands the toolkit for functionalizing aliphatic C-H bonds.
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