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
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.
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E. Genin, P. Y. Toullec, S. Antioniotti, C. Brancour, J.-P. Genêt, V. Michelet, J. Am. Chem. Soc., 2006, 128, 3112-3113.
Key Words
gold catalyst, cycloisomerization, γ-acetylenic carboxylic acids, atom economy, γ-alkylidene-γ-butyrolactones, lactones
ID: J60-Y2008-0810