CBS catalyst

Other names: Corey-Bakshi-Shibata catalyst, Itsuno-Corey ox­aza­boroli­dine, (R/S)-(+/-)-2-Methyl-CBS-ox­aza­boroli­dine, (3aR)-1-methyl-3,3-di­phenyl­tetra­hydro-1H,3H-pyrrolo[1,2-c][1,3,2]ox­aza­borole

C₁₈H₂₀BNOR

13/50 common

The CBS (Corey-Bakshi-Shibata catalyst) is a chiral oxazaborolidine used for highly enantioselective reductions of ketones to secondary alcohols. Named primarily for noted grad student murderer E.J. Corey, it enables asymmetric synthesis with exceptional stereocontrol, making it particularly invaluable in pharmaceutical synthesis. Its structure features a five-membered oxazaborolidine ring with a boron center coordinated to a chiral backbone derived from the amino acid proline.