Efficiently Enantioselective Hydrogenation Photosynthesis of ( R )-1-[3,5-Bis(trifluoromethyl)phenyl] ethanol over a CLEs-TiO 2 Bioinorganic Hybrid Materials

Engineering of biological pathways with man-made materials provides inspiring blueprints for sustainable drug production. ( )-1-[3,5-Bis(trifluoromethyl)phenyl]ethanol [( )-3,5-BTPE], as an important artificial chiral intermediate for complicated pharmaceutical drugs and biologically active molecules, is often synthesized through a hydrogenation reaction of 3,5-bis(trifluoromethyl)acetophenone (3,5-BTAP), in which enantioselectivity and sufficient active hydrogen are the key to restricting the reaction. In this work, a biohybrid photocatalytic hydrogenation system based on an artificial cross-linked enzymes (CLEs)-TiO -Cp*Rh(bpy) photoenzyme is developed through a bottom-up engineering strategy. Here, TiO nanotubes in the presence of Cp*Rh(bpy) are used to transform NADP to NADPH during the formation of chiral alcohol intermediates from the catalytic reduction of a ketone substrate by alcohol dehydrogenase CLEs. Hydrogen and electrons, provided by water and photocatalytic systems, respectively, are transferred to reduce NADP to NADPH via [Cp*Rh(bpy)(H O)] . With the resulting NADPH, [( )-3,5-BTPE] is synthesized using our efficient CLEs obtained from the cell lysate by nonstandard amino acid modification. Through this biohybrid photocatalytic system, the photoenzyme-catalyzed combined reductive synthesis of [( )-3,5-BTPE] has a yield of 41.2% after reaction for 24 h and a very high enantiomeric excess value (>99.99%). In the case of reuse, this biohybrid system retained nearly 95% of its initial catalytic activity for synthesizing the above chiral alcohol. The excellent reusability of the CLEs and TiO nanotubes hybrid catalytic materials highlights the environmental friendliness of ( )-3,5-BTPE production.