(2S,5S)-1,3-Diaza-2-phospha-2-oxo-2-chloro-3-phenylbicyclo[3.3.0]octane: A novel chiral source for borane-mediated catalytic chiral reductions

Abstract

(2S,5S)-1,3-Diaza-2-phospha-2-oxo-2-chloro-3-phenylbicyclo[3.3.0]octane has been successfully employed as a chiral catalytic source for the borane mediated asymmetric reductions of prochiral α-halo ketones to provide the desired (S)-secondary alcohols in 81-91% enantiomeric purities, thus for the first time demonstrating the potential of the N-P(=O)Cl structural framework to generate a recoverable, reusable and air stable catalyst for the asymmetric reduction processes. © 2002 Elsevier Science Ltd. All rights reserved.