Electrocatalytic Oxidant-Free Dehydrogenative C-H/S-H Cross-Coupling
Pan Wang1, Shan Tang1, Pengfei Huang1
1College of Chemistry and Molecular Sciences, Institute for Advanced Studies (IAS), Wuhan University, Wuhan, 430072, Hubei, P.R. China.
Angewandte Chemie (International Ed. in English)
|February 9, 2017
Summary
A new electrocatalytic method enables catalyst- and oxidant-free C-S bond formation via dehydrogenative cross-coupling. This green chemistry approach efficiently synthesizes C-S coupled products from thiols and arenes using electrocatalysis.
Area of Science:
- Organic Chemistry
- Green Chemistry
- Electrocatalysis
Background:
- Traditional C-S bond formation often requires harsh conditions, expensive catalysts, or stoichiometric oxidants.
- Developing sustainable and efficient methods for C-S coupling is crucial in synthetic chemistry.
Purpose of the Study:
- To develop an environmentally friendly electrocatalytic protocol for dehydrogenative C-H/S-H cross-coupling.
- To achieve C-S bond formation under catalyst- and oxidant-free conditions.
Main Methods:
- Utilizing an undivided electrolysis system for the cross-coupling reaction.
- Employing various aryl/heteroaryl thiols and electron-rich arenes as substrates.
Main Results:
- Successful C-S bond formation was achieved under mild, catalyst- and oxidant-free conditions.
- Yields for the C-S bond-formation products ranged from 24-99%.
- A preliminary mechanistic study identified aryl radical cation intermediates as key species.
Conclusions:
- The developed electrocatalytic protocol offers a sustainable and efficient route for C-S bond synthesis.
- This method provides a greener alternative to conventional cross-coupling techniques.
- The findings open avenues for further exploration of electrocatalytic C-H functionalization.
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