Synthesis of Substituted 1H-Indazoles from Arynes and Hydrazones
Pan Li, Chunrui Wu*, Jingjing Zhao, Donald C. Rogness and Feng Shi*
*Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Jinming Campus, Kaifeng, Henan 475004, PR China, Email: cwuhenu.edu.cn, fshihenu.edu.cn
P. Li, C. Wu, J. Zhao, D. C. Rogness, F. Shi, J. Org. Chem., 2012, 77, 3127-3133.
DOI: 10.1021/jo202598e (free Supporting Information)
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The 1H-indazole skeleton can be constructed by a [3 + 2] annulation approach from arynes and hydrazones. Under different reaction conditions, both N-tosylhydrazones and N-aryl/alkylhydrazones can be used to afford various indazoles.
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P. Li, J. Zhao, C. Wu, R. C. Larock, F. Shi, Org. Lett., 2011, 13, 3340-3343.