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Synthesis 2010(9): 1449-1452  
DOI: 10.1055/s-0029-1218682
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Preparation of Substituted Oxazoles by Ritter Reactions of α-Oxo Tosylates

Ping-Shan Lai, Mark S. Taylor*
Department of Chemistry, Lash Miller Laboratories, University of Toronto, 80 St George St., Toronto ON, M5S 3H6, Canada
Fax: +1(416)9788775; e-Mail: mtaylor@chem.utoronto.ca;
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Publication History

Received 20 November 2009
Publication Date:
19 February 2010 (online)

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Abstract

The Lewis acid catalyzed Ritter reaction of α-oxo tosylates with nitriles forms the basis of an efficient synthesis of oxazoles. Oxazoles with various substituents can be readily prepared from inexpensive starting materials.

Key words

heterocycles - cyclizations - nitriles - carbocations - oxazoles - Ritter reaction

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