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Visible-Light-Promoted Hydrogenation of Azobenzenes to Hydrazobenzenes with Thioacetic Acid as the Reductant

Qiao Li, Yanshu Luo, Jianhui Chen and Yuanzhi Xia*

*College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China, Email:

Q. Li, Y. Luo, J. Chen, Y. Xia, J. Org. Chem., 2023, 88, 2443-2452.

DOI: 10.1021/acs.joc.2c02873

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Thioacetic acid mediates a mild catalyst- and metal-free hydrogenation of azobenzenes to hydrazobenzenes in very good yields under visible light irradiation. The method is compatible with a variety of substituents and tolerates other unsaturated functionalities (carbonyl, alkenyl, alkynyl, etc.). Preliminary mechanistic study indicated that the transformation could be a radical process.

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proposed mechanism

Key Words

reduction of azo compounds, thioacetic acid, photochemistry

ID: J42-Y2023