Journal of the American Chemical Society
COMMUNICATION
’ AUTHOR INFORMATION
(11) For an example of a phosphine-catalyzed sila MoritaÀ
BaylisÀHillman reaction of cyclopropenes, see: (a) Chuprakov, S.;
Malyshev, D. A.; Trofimov, A.; Gevorgyan, V. J. Am. Chem. Soc. 2007,
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allenes and dienes and its use in intramolecular enantioselective amina-
tion reactions, see: (b) Shapiro, N. D.; Rauniyar, V.; Hamilton, G. L.;
Wu, J.; Toste, F. D. Nature 2011, 470, 245.
Corresponding Author
’ ACKNOWLEDGMENT
This paper is dedicated to Professor Dieter Hoppe on the
occasion of his 70th birthday. We thank Professor Nicolai
Cramer for helpful discussions and Nathalie E. Wurz for the
preparation of deuterated aldehyde 1b-D. F.L. acknowledges a
study scholarship from the Deutscher Akademischer Austausch
Dienst. The research of F.G. has been supported by the Alfried
Krupp Prize for Young University Teachers of the Alfried Krupp
von Bohlen und Halbach Foundation.
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(15) See the Supporting Information for details.
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2
.
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the σ*CÀCO Me bond is a better acceptor than the σ*CÀAr
2
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dx.doi.org/10.1021/ja202594g |J. Am. Chem. Soc. 2011, 133, 8130–8133