Selective Reduction Of Carbonyl Compounds And Its Application In One-enzyme Cascade Catalyzed By Transaminase

Chiral amine is an important organic compound and an important chiral pharmaceutical intermediate,it is widely used in agrochemicals,medical supplies,etc.In general,there are two main methods for synthesizing chiral amine compounds,one is asymmetric synthesis of a chiral amine using a transition metal catalyst,and the other is the preparation of a chiral amine using a biological enzyme.However,the asymmetric synthesis of chiral amines using transition metal catalysts has the disadvantages of harsh reaction conditions and low ee values for chiral amines.At present,the asymmetric synthesis of co-transaminase for the preparation of chiral amines is very extensive,using relatively inexpensive ketones as substrates,and more amino donors can be used.Therefore,this paper proposes a novel method for removing the equilibrium of intrinsic reactions in the catalytic reaction of transaminase.This scheme connects a process of high-selective hydrogenation of aldehyde promoted by palladium based heterogeneous catalyst using H2 of latm and another process of one-enzyme cascades catalyzed by ?-TA.That is,the selective hydrogenation of aldehyde is applied to the single enzyme system reaction to eliminate the equilibrium problem in the transamination reaction.(1)This solution is a one-enzyme system for the synthesis of chiral amine compounds and does not use expensive coenzymes,reducing economic costs.(2)In the highly selective hydrogenation of aldehydes,we use heterogeneous catalysts and inexpensive H2 as reducing agents instead of toxic hydrides as reducing agents.(3)In the transamination process,we use a relatively inexpensive,readily available ketone as a substrate and an amino donor to synthesize high value-added chiral amine compounds.(4)And for the one-enzyme cascades using ?-TA,the generated coproducts are proposed to be selectively and irreversibly hydrogenated to form alcohols in vitro,functioned as triple purposes of a)removing coproduct aldehyde(ketone)from the reaction system,b)pushing equilibria to product formation,and c)release inhibitions caused by the generated co-product during transamination.This is an effective method for the clean preparation of chiral amines at low-cost.