Synlett 2004(12): 2230-2232  
DOI: 10.1055/s-2004-830891
LETTER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Sugar Oxazolines by Intramolecular Ritter-Like Reaction of d-Fructose Precursors

José L. Jiménez Blancoa, Enrique M. Rubiob, Carmen Ortiz Mellet*a, José M. García Fernández*b
a Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Aptdo. 553, 41071 Sevilla, Spain
Fax: +34(954)624960; e-Mail: mellet@us.es;
b Instituto de Investigaciones Químicas, CSIC, Américo Vespucio 49, Isla de la Cartuja, 41092 Sevilla, Spain
Fax: +34(954)460565; e-Mail: jogarcia@iiq.csic.es;
Further Information

Publication History

Received 20 May 2004
Publication Date:
04 August 2004 (online)

Abstract

Treatment of d-fructopyranose and d-fructofuranose 1,2-O-acetonide derivatives with triflic acid in the presence of a variety of nitriles results in the formation of fused or spiro 2-oxazolines. The reaction implies (i) activation of the anomeric centre with simultaneous isopropylidene cleavage, (ii) nucleophilic addition of the nitrile to the corresponding oxocarbenium cation intermediate and (iii) subsequent trapping of the resulting nitrilium ion species by the remaining hydroxyl group in an intramolecular Ritter-like ­reaction.

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The notation of atoms for NMR data has been kept consistent with that of the parent d-fructose precursor.