Deracemization of Racemic Amines to Enantiopure (R)- and (S)-amines by Biocatalytic Cascade Employing ω-Transaminase and Amine Dehydrogenase

A one-pot deracemization strategy for alpha-chiral amines is reported involving an enantioselective deamination to the corresponding ketone followed by a stereoselective amination by enantiocomplementary biocatalysts. Notably, this cascade employing a omega-transaminase and amine dehydrogenase enabled the access to both (R)-and (S)-amine products, just by controlling the directions of the reactions catalyzed by them. A wide range of (R)-and (S)-amines was obtained with excellent conversions (>80 %) and enantiomeric excess (>99 % ee). Finally, preparative scale syntheses led to obtain enantiopure (R)- and (S)-13 with the isolated yields of 53 and 75 %, respectively.