An Improved Preparation of Oxazolidin-2-one Chiral Auxiliaries

Article abstract of DOI:10.1055/s-1997-743

Reduction of carbamate-blocked amino esters by lithium borohydride (made in situ from sodium borohydride and lithium iodide) forms chiral 4-substituted oxazolidin-2-ones directly. The presence of iodide in the reaction mixture appears to promote the cyclization of the intermediate alkoxyborohydride. This provides a route to these important chiral auxiliaries, employing less hazardous reagents and simpler reaction conditions than do most existing methods.