Highly diastereoselective nitrone cycloaddition onto a chiral ketene equivalent: asymmetric synthesis of cispentacin

…, SJ Roseblade, JK Barrell, R Alexander

Index: Aggarwal, Varinder K.; Roseblade, Stephen J.; Barrell, Juliet K.; Alexander, Rikki Organic Letters, 2002 , vol. 4, # 7 p. 1227 - 1229

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Citation Number: 60

Abstract

A highly diastereoselective intramolecular nitrone cycloaddition onto a chiral ketene equivalent, obtained by Horner-Wadsworth-Emmons olefination of either enantiomer of bis- sulfinyl phosphonate 6, is described. Cycloaddition gave 5, 5-disubstituted isoxazolidine 10 in good yield as a single diastereomer. Catalytic hydrogenolysis of 10 furnished either enantiomer of optically pure cis-2-aminocyclopentane-1-carboxylic acid.