A novel and effective chiral phosphoramide catalyst for the borane-mediated asymmetric reduction of prochiral α-halo ketones

Abstract

The novel chiral phosphoramide, 1,4-bis[(5S)-1,3-diaza-2-phospha-2-oxo-3-phenylbicyclo(3.3.0)octan-2-yl] piperazine, was synthesised and successfully employed as a catalyst in the borane-mediated asymmetric reductions of prochiral α-halo ketones, providing the corresponding α-halo alcohols in 90-95% enantiomeric purities. © 2001 Elsevier Science Ltd.