Zn(OTf)2-Catalyzed Cyclization of Proparyl Alcohols with Anilines, Phenols, and Amides for Synthesis of Indoles, Benzofurans, and Oxazoles through Different Annulation Mechanisms
Manyam Praveen Kumar and Rai-Shung Liu*
*Department of Chemistry, National Tsing-Hua University, Hsinchu, Taiwan 30043, Email: rsliumx.nthu.edu.tw
M. P. Kumar, R.-S. Liu, J. Org. Chem., 2006, 71, 4951-4955.
DOI: 10.1021/jo0606711 (free Supporting Information)
Zn(OTf)2 catalyzed the cyclization of propargyl alcohols with anilines and phenols in toluene at 100°C without additive and gave various indole and benzofuran products with different structures. The cyclization of propargyl alcohols and amides gave oxazoles. Mechanisms for the different substituation patterns are discussed.
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