Cationic Gold(I)-Catalyzed Intramolecular Cyclization of γ-Hydroxyalkynones into 3(2H)-Furanones
Masahiro Egi, Kenji Azechi, Moriaki Saneto, Kaori Shimizu and Shuji Akai*
*School of Pharmaceutical Sciences, University of Shizuoka, 52-1, Yada, Suruga-ku, Shizuoka, Shizuoka 422-8526, Japan, Email: akaiu-shizuoka-ken.ac.jp
M. Egi, K. Azechi, M. Saneto, K. Shimizu, S. Akai, J. Org. Chem., 2010, 75, 2123-2126.
DOI: 10.1021/jo100048j (free Supporting Information)
A catalyst generated from the combination of (p-CF3C6H4)3PAuCl and AgOTf cyclizes readily available γ-hydroxyalkynones under mild conditions to give substituted 3(2H)-furanones in good yields. This method is also applicable to the preparation of 2,3-dihydro-4H-pyran-4-ones.
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