Theoretical Studies On Hydroamination Of Olefins Catalyzed By Copper Complexes

In organic synthesis,the hydroamination is one of the most important means for constructing C–N bonds and is widely used in natural products,pharmaceuticals,fine chemicals and materials industries.In recent years,transition metal copper-catalyzed the hydroamination has become an efficient way to build C–N bonds.Such reactions have the advantages of high yield and high enantioselectivity.Therefore,the theoretical study on the catalytic hydroamination by transition metal copper has important theoretical significa nce.In this thesis,density-functional theory(DFT)was used to study the mechanism of transition metal copper-catalyzed hydroamination and Cope-type hydroamination of alkene.The main contents of this study include the following two parts:1.Copper-hydride-catalyzed reductive relay hydroamination for the synthesis of γ-chiral amines was systematically studied by density functional theory(DFT)at the M06L/6-311+G(d,p)-SDD//M06L/6-31G(d)-SDD calculaton levels.By studying a series of steps in the catalytic cycle,such as,Markovniko v hydrocupration,elimination of β-alkoxide,insertion of terminal alkene,electrophilic attack of aminating reagents,and the formation of C–N bonds.The most favorable pathway was found to be the Re-attack of the catalyst with the allylic ester to produce the S-configuration product.This result is consistent with the experiment.In addition,non-covalent interaction(NCI)analysis reveal that the transition state Re-TS1 has stronger non-covalent interactions.The frontier molecular orbital(FMO)analysis shows that a larger LUMO-HOMO gap in transition state Si-TS1.2.The mechanism of the catalytic synthesis of nitrones by transition metal copper-catalyzed Cope-type hydroamination of cyclopropene and oxime was studied in detail through density functional theory(DFT)calculations at the level of M06L/6-311+G(d,p)//CAM-B3LYP/6-311+G(d,p)//B3LYP/6-31G(d).The calculation results indicate that the catalyst firstly coordinated with cyclopropene and then reacted with the amination reagent is dynamic favorable.In contrast,the catalyst is thermodynamic supported by reaction with the amination reagent firstly and then coordinated with cyclopropene.The calculations also show that the step that determines the product’s configuration is the migration insertion of C=C bond and protonation.In addition,non-covalent interaction(NCI)analysis found that the steric hindrance was small in the transition state TS-SS,and the non-covalent interaction was relatively large.The natural bond orbital(NBO)charge analysis sho ws that Cu is positively charged and O is negatively charged.