Coupled chemoenzymatic transfer hydrogenation catalysis for enantioselective reduction and oxidation reactions

摘要: Abstract Stereoselective reductions of prochiral ketones were performed using a new thermophilic, NAD-dependent alcohol dehydrogenase from Thermus sp. (TADH). The enzyme was produced on 2L-scale recombinant Escherichia coli and purified by simple, one-step heat treatment procedure yielding 220 mg pure enzyme. Regeneration NADH catalyzed the organometallic complex [Cp*Rh(bpy)(H 2 O)] 2+ formate as reducing agent. catalytic performance in terms total number cycles per hour achieved herein (up to 1500 more than 400 h −1 , respectively), are highest reported for non-enzymatic nicotinamide regeneration system so far. Chemoenzymatic reduction reactions two liquid phase setup gramme-scale, example, 1.3 g enantiopure (1 S ,3 )-3-methylcyclohexanol obtained after purification. volumetric productivity reached up 3.9 mM h with an average 2.6 mM h (5.3 g L  d ) over 10 h. In addition, chemoenzymatic oxidations utilizing same catalyst set molecular oxygen terminal electron acceptor performed. Thus, preparative value transfer hydrogenations coupled especially thermophilic ADHs demonstrated.