Cu(II) carboxylate arene C─H functionalization: Tuning for nonradical pathways
Fanji Kong1, Shusen Chen2, Junqi Chen1
1Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
Science Advances
|August 24, 2022
Summary
Copper(II) salts enable efficient, non-directed C-H acetoxylation of arenes like benzene. This catalytic process is recyclable and reusable, offering a sustainable method for arene functionalization.
Area of Science:
- Organic Chemistry
- Catalysis
- Organometallic Chemistry
Background:
- Direct C-H functionalization of arenes remains a significant challenge in organic synthesis.
- Developing efficient and sustainable catalytic systems for arene modification is crucial.
Purpose of the Study:
- To report a novel carbon-hydrogen acetoxylation of nondirected arenes using copper(II) salts.
- To investigate the mechanism and recyclability of the catalytic system.
Main Methods:
- Utilized simple copper(II) salts for the acetoxylation of benzene and toluene.
- Employed experimental and computational studies to elucidate the reaction mechanism.
- Investigated the isolation, recycling, and in situ regeneration of copper(II) salts.
Main Results:
- Achieved over 80% yield for carbon-hydrogen acetoxylation and related esterifications.
- Demonstrated a 2.4% conversion of benzene by adjusting the benzene to copper(II) salt ratio.
- Identified a nonradical Cu(II)-mediated organometallic pathway for arene C-H functionalization.
- Showcased the recyclability and reusability of copper(II) salts with consistent reactivity.
Conclusions:
- Developed an efficient and sustainable method for arene C-H acetoxylation and esterification.
- The copper(II)-catalyzed process offers a viable route for arene functionalization with potential for industrial application.
- The established catalytic system highlights the possibility of in situ regeneration and continuous reaction cycles.
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