Reactions of lithiumderivatives of chiral phosphine oxides with ketones (e.g cyclohexanone, cyclobutanone, valerophenone) and Me3SiCl proceed with excellent levels of syn selectivity. In contrast, reactions with methyl iodide are moderately anti selective and those with aldehydes show no selectivity whatsoever.
Chiral phosphine oxides and chiral esters in stereoselective intermolecular acylation reactions of phosphine oxides
作者:David Cavalla、Catherine Guéguen、Adam Nelson、Peter O'Brien、Matthew G Russell、Stuart Warren
DOI:10.1016/0040-4039(96)01612-7
日期:1996.10
Single diastereomers of β-keto phosphineoxides have been generated from intermolecular acylation of phosphineoxides using either chiral esters or chiral phoshine oxides. In most cases, reduction of the ketone products was not affected by the presence of extra chiral centres. Some mechanistic points of interest in the acylation reactions are discussed.