Kinetic Resolution and Deracemization of Racemic Amines Using a Reductive Aminase

The NADP(H)‐dependent reductive aminase from Aspergillus oryzae ( Asp RedAm) was combined with an NADPH oxidase (NOX) to develop a redox system that recycles the co‐factor. The Asp RedAm‐NOX system was applied initially for the kinetic resolution of a variety of racemic secondary and primary amines to yield S ‐configured amines with enantiomeric excess ( ee ) values up to 99 %. The addition of ammonia borane to this system enabled the efficient deracemization of racemic amines, including the pharmaceutical drug rasagiline and the natural product salsolidine, with conversions up to >98 % and >99 % ee Furthermore, by using the Asp RedAm W210A variant it was possible to generate the opposite R enantiomers with efficiency comparable to, or even better than, the wildtype Asp RedAm.