Enantiomerically pure chiral amines are of increasing value in the preparation of bioactive compounds， pharmaceuticals， and agrochemicals. ω-Transaminase (ω-TA) is an ideal catalyst for asymmetric amination because of its excellent enantioselectivity and wide substrate scope. To shift the equilibrium of reactions catalyzed by ω-TA to the side of the amine product， an upgraded N fixation system based on bioelectrocatalysis was developed to realize the conversion from N to chiral amine intermediates. The produced NH was in situ reacted with l-alanine dehydrogenase to generate alanine with NADH as a coenzyme. ω-TA transferred the amino group from alanine to ketone substrates and finally produced the desi... More
Enantiomerically pure chiral amines are of increasing value in the preparation of bioactive compounds， pharmaceuticals， and agrochemicals. ω-Transaminase (ω-TA) is an ideal catalyst for asymmetric amination because of its excellent enantioselectivity and wide substrate scope. To shift the equilibrium of reactions catalyzed by ω-TA to the side of the amine product， an upgraded N fixation system based on bioelectrocatalysis was developed to realize the conversion from N to chiral amine intermediates. The produced NH was in situ reacted with l-alanine dehydrogenase to generate alanine with NADH as a coenzyme. ω-TA transferred the amino group from alanine to ketone substrates and finally produced the desired chiral amine intermediates. The cathode of the upgraded N fixation system supplied enough reducing power to synchronously realize the regeneration of reduced methyl viologen (MV) and NADH for the nitrogenase and l-alanine dehydrogenase. The coproduct， pyruvate， was consumed by l-alanine dehydrogenase to regenerate alanine and push the equilibrium to the side of amine. After 10 h of reaction， the concentration of 1-methyl-3-phenylpropylamine achieved 0.54 mM with the 27.6% highest faradaic efficiency and >99% enantiomeric excess (ee). Because of the wide substrate scope and excellent enantioselectivity of ω-TA， the upgraded N fixation system has great potential to produce a variety of chiral amine intermediates for pharmaceuticals and other applications.
