Visible-Light-Promoted Diboron-Mediated Transfer Hydrogenation of Azobenzenes to Hydrazobenzenes

Menghui Song, Hongyan Zhou, Ganggang Wang, Ben Ma, Yajing Jiang, Jingya Yang*, Congde Huo and Xi-Cun Wang*

*College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China, Email: yangjynwnu.edu.cn, wangxicunnwnu.edu.cn

M. Song, H. Zhou, G. Wang, B. Ma, Y. Jiang, J. Yang, C. Huo, X.-C. Wang, J. Org. Chem., 2021, 86, 4804-4811.

DOI: 10.1021/acs.joc.1c00394

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Abstract

A visible-light-promoted transfer hydrogenation of azobenzenes proceeds smoothly in methanol at ambient temperature in the presence of B₂pin₂ through a radical pathway. The reaction reduces a broad range of azobenzenes to the corresponding hydrazobenzenes in very good yields.

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proposed mechanism

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Key Words

reduction of azocompounds, bis(pinacolato)diboron, photochemistry

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ID: J42-Y2021