Synfacts 2009(9): 1010-1010  
DOI: 10.1055/s-0029-1217642
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart ˙ New York

Cyclobutanones via Ring Expansion of Allenylcyclopropanols

Contributor(s): Mark Lautens, Jacki Kitching
F. Kleinbeck, F. D. Toste*
University of California, Berkeley, USA
Further Information

Publication History

Publication Date:
21 August 2009 (online)

Significance

The gold(I)-catalyzed enantioselective ring expansion of allenylcyclopropanols is described. This protocol provides cyclobutanones with a vinyl-substituted quaternary stereogenic center in good yield and with high enantioselectivity. The proposed mechanism for the reaction involves ring expansion by a Wagner-Meerwein shift and is reported to be the first account of an enantioselective gold-catalyzed 1,2-alkyl migration.