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Updated: Jun 11, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Electron-donor-acceptor (EDA) complex-driven regioselective vicinal and oxidative geminal functionalization of
Dinabandhu Barik1, Nikita Chakraborty1, Ashish K Sahoo1
1Department of Chemistry, Indian Institute of Technology Guwahati, 781039, Assam, India. patel@iitg.ac.in.
This study introduces a new method for modifying alkynes using visible light. The process allows for the selective addition of sulfur-containing groups and carbonyls, offering versatile synthetic pathways.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
- Photochemistry
Background:
- Alkyne functionalization is crucial for synthesizing complex organic molecules.
- Developing regioselective and efficient methods for installing multiple functionalities remains a challenge.
- Visible-light photoredox catalysis offers a sustainable approach to radical generation and organic transformations.
Purpose of the Study:
- To develop a visible-light-initiated method for the regioselective thiosulfonylation of alkynes.
- To explore the generation of sulfonyl and thiyl radicals from organic thiosulfonates.
- To achieve simultaneous installation of carbonyl, sulfonyl, and thiyl functionalities or vicinal thiolation and sulfonylation.
Main Methods:
- Visible-light irradiation of electron-donor-acceptor (EDA) complexes.
- Utilizing organic thiosulfonates as radical precursors (sulfonyl or thiyl radicals).
- Employing base and solvent switchable conditions to control reaction pathways.
Main Results:
- Achieved regioselective vicinal and oxidative geminal thiosulfonylation of alkynes.
- Demonstrated switchable conditions for generating either sulfonyl (RSO2•) or thiyl (RS•) radicals.
- Successfully performed simultaneous installation of carbonyl, sulfonyl, and thiyl groups in one pot.
- Developed an alternative pathway for vicinal thiolation and sulfonylation.
Conclusions:
- A novel and versatile visible-light-driven thiosulfonylation of alkynes has been established.
- The method offers tunable control over radical generation and functional group installation.
- This approach provides efficient access to diverse sulfur-containing organic compounds.
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