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Synthesis 2009(1): 43-55  
DOI: 10.1055/s-0028-1083280
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

α-Metallated O-2-Alkenyl Carbamates: Synthetic Equivalents of Chiral Homoenolates and Materials for Asymmetric Homoaldol Reaction

Dieter Hoppe*
Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster, Germany
Fax: +49(251)8339772; e-Mail: dhoppe@uni-muenster.de ;
Further Information

Publication History

Received 21 October 2008
Publication Date:
12 December 2008 (online)

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Abstract

The review article provides a personal overview on the development and application in enantioselective synthesis of non­racemic chiral homoenolate reagents, based on allylic N,N-dialkylcarbamates and the ideas behind it. Further, the impact of these results, concerning stereoselective deprotonation, mainly under the influence of the chiral diamine (-)-sparteine, for the generation of a wide range of chiral building blocks is briefly presented.

Key words

asymmetric synthesis - homoenolates - stereoselective deprotonation - chiral carbanions - (-)-sparteine

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23

In my opinion, only few experiments are indeed stupid ones, because one can learn a lot from many of the results.

51

We were able to produce five-gram batches of (+)-32 on several occasions.

65

See references 55a and 57.