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Updated: Jul 13, 2026
05:34
Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Sulfonated N-heterocyclic carbenes for Suzuki coupling in water
Christoph Fleckenstein1, Sutapa Roy, Steffen Leuthäusser
1Anorganische Chemie im Zintl-Institut, Petersenstr. 18, 64287 Darmstadt, Germany.
Chemical Communications (Cambridge, England)
|July 5, 2007
Summary
Sulfonated imidazolium and imidazolinium salts were synthesized and used in palladium complexes for aqueous Suzuki coupling reactions. These water-soluble catalysts efficiently coupled aryl chlorides in water.
Area of Science:
- Organometallic Chemistry
- Green Chemistry
- Catalysis
Background:
- Suzuki coupling reactions are crucial for C-C bond formation.
- Aryl chlorides are challenging substrates for Suzuki coupling due to their low reactivity.
- Developing water-soluble catalysts is essential for environmentally friendly chemical processes.
Purpose of the Study:
- To synthesize novel sulfonated imidazolium and imidazolinium salts.
- To prepare palladium complexes with these ligands for catalysis.
- To evaluate the efficacy of these complexes in aqueous Suzuki coupling reactions of aryl chlorides.
Main Methods:
- Synthesis of sulfonated imidazolium and imidazolinium salts.
- Formation of palladium complexes with N,N'-bis(2,6-dialkyl-4-SO(3)(-)-phenyl)imidazol-2-ylidene and N,N'-bis(2,6-dialkyl-4-SO(3)(-)-phenyl)-4,5-dihydroimidazol-2-ylidene ligands.
- Application of the synthesized Pd-complexes in aqueous Suzuki coupling reactions using aryl chlorides as substrates.
Main Results:
- Successful synthesis of water-soluble sulfonated imidazolium and imidazolinium salts.
- Formation of stable palladium complexes with the synthesized ligands.
- Effective catalysis of aqueous Suzuki coupling reactions involving aryl chlorides, demonstrating the utility of the water-soluble catalysts.
Conclusions:
- The synthesized sulfonated imidazolium and imidazolinium salts form effective palladium catalysts for Suzuki coupling.
- These water-soluble catalysts enable the coupling of challenging aryl chloride substrates in aqueous media.
- The study highlights a greener approach to Suzuki coupling reactions using water as a solvent.
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