Hydrogen‐Borrowing Alcohol Bioamination with Coimmobilized Dehydrogenases

The amination of alcohols is an important transformation in chemistry. The redox‐neutral (i.e., hydrogen‐borrowing) asymmetric amination of alcohols is enabled by the combination of an alcohol dehydrogenase (ADH) with an amine dehydrogenase (AmDH). In this work, we enhanced the efficiency of hydrogen‐borrowing biocatalytic amination by co‐immobilizing both dehydrogenases on controlled porosity glass FeIII ion‐affinity beads. The recyclability of the dual‐enzyme system was demonstrated (5 cycles) with total turnover numbers of >4000 and >1000 for ADH and AmDH, respectively. A set of (S)‐configured alcohol substrates was aminated with up to 95 % conversion and >99 % ee (R). Preparative‐scale amination of (S)‐phenylpropan‐2‐ol resulted in 90 % conversion and 80 % yield of the product in 24 h. Something borrowed: We co‐immobilize an alcohol dehydrogenase (ADH) and an amine dehydrogenase (AmDH) on controlled porosity glass FeIII affinity beads to perform the hydrogen‐borrowing amination of (S)‐configured alcohols with up to 95 % conversion, >99 % ee. Recyclability of the dual‐enzyme system is demonstrated, whereas the total turnover numbers are >4000 and >1000 for ADH and AmDH, respectively.