Investigation of the configurational stability of lithiated phosphine oxides using diastereomerically pure and enantiomerically enriched phosphine oxides

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Peter O'Brien and Stuart Warren


Abstract

Lithiation of racemic but diastereomerically pure phosphine oxides followed by electrophilic quench indicates that lithiated phosphine oxides are not configurationally stable over a period of minutes in THF at –78 °C. These results have been verified using an optically active phosphine oxide: lithiation and in situ quench experiments with Me3SiCl and cyclobutanone indicate that the lithium derivatives are not configurationally stable even on the timescale of their reaction with these electrophiles.


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