Au₂O₃ as a Stable and Efficient Catalyst for the Selective Cycloisomerization of γ-Acetylenic Carboxylic Acids to γ-Alkylidene-γ-Butyrolactones

Patrick Yves Toullec, Emilie Genin, Sylvain Antoniotti, Jean-Pierre Genêt, Véronique Michelet*

*Laboratoire de Synthèse Sélective Organique et Produits Naturels, ENSCP, UMR 7573, 11 Rue P. et M. Curie, 72231 Paris Cedex 05, France, Email: veronique-micheletenscp.fr

P. Y. Toullec, E. Genin, S. Antoniotti, J.-P. Genêt, V. Michelet, Synlett, 2008, 707-711.

DOI: 10.1055/s-2008-1032108

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Abstract

A general, efficient, and convenient cyclization of alkynes bearing carboxylic acids to the corresponding γ-alkylidene-γ-butyrolactones in the presence of commercially available Au₂O₃ shows a high degree of chemo-, regio-, and stereoselectivity. The 5-exo mode of cyclization and anti auration are a general trend for the Au₂O₃ catalyst.

see article for more examples

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Room Temperature Au(I)-Catalyzed exo-Selective Cycloisomerization of Acetylenic Acids: An Entry to Functionalized γ-Lactones

E. Genin, P. Y. Toullec, S. Antioniotti, C. Brancour, J.-P. Genêt, V. Michelet, J. Am. Chem. Soc., 2006, 128, 3112-3113.

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Key Words

gold catalyst, cycloisomerization, γ-acetylenic carboxylic acids, atom economy, γ-alkylidene-γ-butyrolactones, lactones

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ID: J60-Y2008-0810