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In Situ Generated Gold Nanoparticles on Active Carbon as Reusable Highly Efficient Catalysts for a C -C Stille
Julia Holz1, Camilla Pfeffer1, Hualiang Zuo2
1Universität Stuttgart, Institut für Organische Chemie, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
Angewandte Chemie (International Ed. in English)
|April 24, 2019
Summary
Gold nanoparticles are highly active catalysts for carbon-carbon bond formation, outperforming palladium in specific cross-coupling reactions. This discovery offers efficient and reusable gold catalysts for industrial applications.
Area of Science:
- Catalysis
- Nanomaterials
- Organic Synthesis
Background:
- Gold nanoparticle catalysts are vital in industrial processes but rarely used for C-C cross-coupling reactions, where palladium catalysts typically excel.
- Traditional methods often rely on palladium, limiting the exploration of gold's potential in these specific transformations.
Purpose of the Study:
- To investigate the efficacy of in situ formed gold metal nanoparticles as catalysts for C-C bond formation.
- To explore a novel application of gold catalysts in cross-coupling reactions, aiming for superior performance compared to palladium.
Main Methods:
- In situ formation of gold metal nanoparticles on an active carbon support.
- Catalysis of cross-coupling reactions between allylstannanes and activated alkylbromides.
Main Results:
- Gold nanoparticle catalysts demonstrated high activity in forming C-C bonds via cross-coupling of allylstannanes and activated alkylbromides.
- Achieved high turnover numbers (up to 29,000), indicating significant catalytic efficiency.
- The use of active carbon support facilitated convenient catalyst recovery and reuse, enhancing sustainability.
Conclusions:
- In situ formed gold metal nanoparticles are highly effective catalysts for specific C-C cross-coupling reactions.
- Gold catalysts can outperform palladium catalysts in the coupling of organic halides with organometallic reagents, presenting a significant advancement.
- The developed method offers an efficient, recoverable, and reusable catalytic system for organic synthesis.
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