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TBAI/K2S2O8-Promoted [4 + 2] Annulation of Ketene N,S-Acetals and N-Tosylhydrazones toward Pyridazines

Zhuqing Liu, Jiang Lou* and Jiaqi Xiao*

*Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, P. R. China, Email:,

Z. Liu, J. Lou, J. Xiao, Org. Lett., 2021, 23, 1606-1610.

DOI: 10.1021/acs.orglett.1c00026

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A TBAI/K2S2O8-promoted [4 + 2] annulation of ketene N,S-acetals, and N-tosylhydrazones provides a variety of trisubstituted pyridazines in good yields. The method offers a broad substrate scope and a good functional group tolerance.

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proposed mechanism

Key Words

pyridazines, potassium peroxydisulfate

ID: J54-Y2021