Highly Diastereoselective Nitrone Cycloaddition onto a Chiral Ketene Equivalent: Asymmetric Synthesis of Cispentacin
作者:Varinder K. Aggarwal、Stephen J. Roseblade、Juliet K. Barrell、Rikki Alexander
DOI:10.1021/ol025665f
日期:2002.4.1
[reaction: see text] A highly diastereoselective intramolecular nitrone cycloaddition onto a chiral ketene equivalent, obtained by Horner-Wadsworth-Emmons olefination of either enantiomer of bis-sulfinyl phosphonate6, 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