Primary Amine Catalysts For Catalytic Asymmetric Michael Addition Reaction Of Theoretical Research

Chirality is existent commonly phenomenon in nature. They are almost chiral, suchas proteins, nucleic acids, polysaccharides (starch, cellulose, etc.) and enzymes which areacting as the important foundation of life activity. Chiral compounds are extensively usingfor organic chemistry, biochemistry, pharmaceutical chemistry, and polymer materials.Currently it has become a type of significant catalysts in the field of asymmetric catalysisthat chiral primary amine posesses the feature of high catalytic activity and asymmetricinduction, easy preparation and modification. In recent years, chiral primary amines havebeen successfully applied to the Aldol reaction, Michael addition reaction, Mannichreaction, and asymmetric catalysis of Diels - Alder reaction. At present, most of theprimary amine catalyst with high enantioselectivity is containing secondary amineskeleton or other chiral unit. There is very important theoretical and practical significancewith the research of asymmetric organic catalytic reaction being not only enriching thecontents of the chemistry but also useful for mankind. Theoretical studies oforganocatalytic asymmetric reactions not only can understand the reaction mechanismfully from the molecular level but also can explain the experimental phenomenons. It alsocan make the function of organocatalyst and the origin of enantioselectivity for thecatalyzed reaction clear.In this dissertation, we studied the Michael addition reactions catalyzed byprimary-secondary diamine catalyst. Theoretical studies by computational methods canexplain the reaction mechanism and the essential effect of the catalyst frommicromechanism. The results can provide a theoretical direction for developing new type,high effective organocatalysts and novel organocatalytic asymmetric reactions.The valuable results in this dissertation can be summarized as follows:The Michael addition of dimethyl malonate to chalcone catalyzed byprimary-secondary diamine catalyst has been investigated by use of the density functionalmethod. The results show that there are two configurations for the products of the reaction,in which (S)-configuration product is favored over the (R)-configuration product. For the whole catalytic cycle, the rate-determining step is the first step. The enantioselectivity ofthe Michael addition reaction is controlled by the C–C bond-formation step. Thecalculated ee value is approximate to the experimental data. The present DFT studyexplains the experimental results well and provides the details of the reactionmechanisms.The Michael addition of nitroalkanes to enones catalyzed by primary-secondarydiamine catalyst has been investigated by use of the density functional method. Theresults show that there are two configurations for the products of the reaction, in which(S)-configuration product is favored over the (R)-configuration product. For the wholecatalytic cycle, the rate-determining step is the second step. The enantioselectivity of theMichael addition reaction is controlled by the C–C bond-formation step. The calculatedee value is approximate to the experimental data. The present DFT study explains theexperimental results well and provides the details of the reaction mechanisms.The Michael addition of indolin-3-ones to enones catalyzed by primary-secondarydiamine catalyst has been investigated by use of the density functional method. Theresults show that there are two configurations for the products of the reaction, in which(S)-configuration product is favored over the (R)-configuration product. For the wholecatalytic cycle, the rate-determining step is the second step. The enantioselectivity of theMichael addition reaction is controlled by the C–C bond-formation step. The calculatedee value is approximate to the experimental data. The present DFT study explains theexperimental results well and provides the details of the reaction mechanisms.The present results will stimulate not only the development of novel organocatalystfor Michael addition but also the expansion of the scope of primary-secondary diaminecatalysis.