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Synthesis 2002(8): 1115-1120
DOI: 10.1055/s-2002-31962
FEATUREARTICLE
© Georg Thieme Verlag Stuttgart · New York

Conversion of Imines into C,N-Dimagnesiated Compounds and Trapping with Electrophiles. One-Pot Access to 1-Azaspirocyclic Framework

Vincent Gandon, Philippe Bertus, Jan Szymoniak*
Réactions Sélectives et Applications, CNRS and Université de Reims, 51687 Reims Cedex 2, France
Fax: +33(3)26913166; e-Mail: jan.szymoniak@univ-reims.fr;
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Publication History

Received 4 January 2002
Publication Date:
03 June 2002 (online)

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Abstract

Under selected conditions, the Zr-catalyzed reaction of EtMgCl with imines produces C,N-dimagnesiated compounds, which can be further trapped with electrophiles. The overall transformation provides a new route to bifunctional or cyclic nitrogen-containing compounds. Particularly, 1-azaspirocyclic γ-lactams, pyrrolidines and azetidines can be obtained in this way.

Key Words

azetidines - Grignard reagents - imines - spiro compounds - zirconium

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5

We have previously demonstrated the feasibility of coupling F with benzaldehyde, see ref. [1]

6

The F:E ratio could easily be established by deuterolysis, see: ref. [1]