Hydroboration of prochiral olefins with chiral Lewis base–borane complexes: relationship to the mechanism of hydroboration

Abstract

Alcohols with up to 19% enantiomeric excess were obtained on hydroboration/oxidation of representative prochiral olefins using N-isobornyl-N-methylaniline–borane or N-benzyl-N-isopropyl-α-methylbenzylamine–borane indicating that the Lewis base is present in the hydroboration transition state.