An Effective and Useful Synthesis of Enantiomerically Enriched Arylglycinols

Abstract

A two-step synthesis of racemic arylglycinols, together with a simple and straightforward methodology for their resolution, is described. This method constitutes a practical means of preparing racemic and optically pure electron-rich or electron-poor substituted arylglycinols, useful building blocks for the synthesis of biologically active molecules and chiral ligands. All of the chiral β-amino alcohols 5−8 were isolated in good chemical yields and with excellent enantiomeric excesses: up to 99% in the cases of the arylglycinols 7 and 8. Chiral fluoroaromatic vicinal amino alcohols can also be obtained with good enantiopurity using such a procedure. The key step of the strategy presented is an easy chromatographic separation of the diastereoisomeric amides prepared from acetyl mandeloyl chloride. The absolute configuration of the perfluorinated amino alcohols 5 was determined by X-ray analysis of the corresponding amide 14a.