A Chemoenzymatic Cascade for the Formal Enantioselective Hydroxylation and Amination of Benzylic C-H Bonds

Abstract

We report the synthesis and characterization of an artificial peroxygenase (CoN4SA-POase) with CoN4 active sites by supporting single-atom cobalt on polymeric carbon nitrogen, which exhibits high activity, selectivity, stability, and reusability in the oxidation of aromatic alkanes to ketones. Density functional theory calculations reveal a different catalytic mechanism for the artificial peroxygenase from that of natural peroxygenases. In addition, continuous-flow systems are employed to combine CoN4SA-POase with enantiocomplementary ketoreductases as well as an amine dehydrogenase, enabling the enantioselective synthesis of chiral alcohols and amines from hydrocarbons with significantly improved productivity. This work, emulating nature and beyond nature, provides a promising design concept for heme enzyme-based transformations.