CBS reduction

The CBS reduction, in full the Corey-Bakshi-Shibata reduction, is an organic reaction which transforms ketones enantioselectively into alcohols. This is done by using the so-called CBS catalyst, a bicyclic boron-containing proline derivative, along with diborane as the proton donor.

The oxazaborolidine reagent which mediates the enantioselective reduction was previously developed by the laboratory of Itsuno, and thus this transformation may more properly be called the Itsuno-Corey oxazaborolidine reduction.