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Metal-Free Cascade [4 + 1] Cyclization Access to 4-Aryl-NH-1,2,3-triazoles from N-Tosylhydrazones and Sodium Azide

Wen-Ming Shu*, Xun-Fang Zhang, Xiang-Xiang Zhang, Min Li, An-Jing Wang and An-Xin Wu*

*College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou 434023; College of Chemistry, Central China Normal University, Wuhan 430079, P.R. China, Email:,

W.-M. Shu, X.-F. Zhang, X.-X. Zhang, M. Li, A.-J. Wang, A.-X. Wu, J. Org. Chem., 2019, 84, 14919-14925.

DOI: 10.1021/acs.joc.9b02250 (free Supporting Information)


A molecular iodine-mediated coupling cyclization reaction of N-tosylhydrazones with sodium azide provides valuable 4-aryl-NH-1,2,3-triazoles via sequential C-N and N-N bond formation. Mechanistic studies suggest that the nitrogen atoms of the 1,2,3-triazoles are not entirely from sodium azide.

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proposed mechanism

Key Words

1,2,3-triazoles, iodine

ID: J42-Y2019