Synlett 2004(12): 2051-2065  
DOI: 10.1055/s-2004-832816
ACCOUNT
© Georg Thieme Verlag Stuttgart · New York

Highly Diastereoselective Syntheses of Propargylic Acid and Homopropargylic Systems

Franck Ferreira, Aurélien Denichoux, Fabrice Chemla*, Joseph Bejjani
Laboratoire de Chimie Organique, UMR 7611, Case Courrier 183, Tour 44-45 2ème étage, Université Pierre et Marie Curie, 4 place Jussieu, 75252 Paris cedex 05, France
Fax: +33(1)44277567; e-Mail: fchemla@ccr.jussieu.fr;
Further Information

Publication History

Received 23 March 2004
Publication Date:
08 September 2004 (online)

Abstract

The results of our research dealing with the stereoselective synthesis of propargylic and homopropargylic systems are summarized. In a first part, the stereoselective formation of syn- or anti-disubstituted homopropargylic alcohols from acetylenic oxiranes through SN2 or double SN2′ has been developed. Thus, the two diastereomers of a given homopropargylic alcohol are stereospecifically available. The great impact of Lewis acid activation on the regioselectivity of the ring-opening reactions of propargylic oxiranes is also detailed. In a second part, the preparation and uses of new acetylenic/allenic carbenoids are overviewed; their reactivity towards carbonyl compounds and imines is examined, leading to the highly stereoselective synthesis of acetylenic chlorohydrins, ­oxiranes and aziridines.

1 Homopropargylic Alcohols as Interesting Targets

2 A Diastereodivergent Synthesis of Homopropargylic Alcohols

2.1 Regioselective Ring-Opening of Acetylenic Oxiranes: A Challenge!

2.2 The Dramatic Influence of BF3·OEt2 Activation on the Regioselectivity

2.3 Nucleophilic Substitution with Retention of Configuration: Thanks to the Triple Bond

3 Laziness as a Good Motivation for Research: Design and Uses of a New Propargylic Carbenoid

3.1 Addition of Propargylic Carbenoids to Aldehydes: Dramatic Influence of Aldehyde on the Stereoselectivity

3.1.1 Highly Diastereoselective Access to Non-Aromatic Acetylenic Oxiranes

3.1.2 Unexpected Behavior of Aromatic Aldehydes: One or Two Transition States?

3.1.3 A New Propargylic Lithiocarbenoid: Curtin-Hammett Principle and Metallotropic Equilibrium

3.2 What About the Addition of Propargylzinc Carbenoids onto Imines?

3.2.1 Highly Diastereoselective Synthesis of Acetylenic N-Benzyl and N-H Aziridines

3.2.2 Unexpected Behavior of N-Sulfonylimines: Chelate versus Open Transition State?

3.2.2 En Route to the Stereoselective Synthesis of Enantiopure Acetylenic Aziridines

4 Conclusion and Perspectives

45

Unpublished results.