Stereoselective ring opening of chiral oxazolidines by reformatsky reagents: an enantioselective entry to β-amino esters.

C Andrés, A González, R Pedrosa, A Pérez-Encabo

Index: Andres, Celia; Gonzalez, Alfonso; Pedrosa, Rafael; Perez-Encabo, Alfonso Tetrahedron Letters, 1992 , vol. 33, # 20 p. 2895 - 2898

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Citation Number: 28

Abstract

Abstract Chiral oxazolidines obtained by condensation of aldehydes with (-).(R)-or (+).(S)-N- benzylphenylglycinol react with the Reformatsky reagent derived from ethyl bromoacetate, in mild reaction conditions (Et 2 O or CH 2 Cl 2, 0 C, 15-60 min), leading to ethyl β-amino carboxylates in moderate to good diastereomeric excess (60-92%). These ring opening products are transformed into primary β-aminoesters, in one step, by debenzylation with H ...