Baker's yeast (BY) has been utilized for the kinetic resolution of α-stereogenic carbonyl compounds. The enzyme selectively reduces one enantiomer, yielding a highly enantioenriched alcohol and ketone, as shown below.
Bakers yeast has also been used in the kinetic resolution of secondary benzylic alcohols by oxidation. While excellent ees of the recovered alcohol have been reported, they typically require >60% conversion, resulting in diminished yields. Bakers yeast has also been used in the kinetic resolution via reduction of β-ketoesters. However, given the success of Noyoris resolution of the same substrates, detailed later in this article, this has not seen much use.