Study On Asymmetric Allylic Substitution Of Methyl Ketimine

Transition metal-catalyzed substitution reactions of allyl compounds and their derivatives play an important role in organic chemistry.It is an important method to form C-C bonds and C-hetero bonds.And it is widely used in the synthesis of many biologically active compounds and natural products.Because this method can not only synthesize many compounds with various structures,but also the reaction products can be easily and selectively functionalized.It is an important intermediate for the synthesis of many important compounds and natural products.Because methyl groups in methylketimines have good nucleophilicity,this topic uses methyl ketimines as nucleophiles to systematically study the selectivity of these compounds in a controlled manner.The asymmetric allylic substitution reaction has achieved satisfactory results.In the first chapter,the allylic substitution reaction is introduced,and the origin,development and current status of the allylic substitution reaction are reviewed.Based on the research progress of electrophiles,transition metal catalysts and various nucleophiles catalyzed by iridium in the allylic substitution reaction,the research scheme and content of this paper are further proposed.In the second chapter,the selective controllable asymmetric allylation reaction of allyl esters with methyl functional groups in cyclic sulfonimides catalyzed by chiral iridium complexes was studied in detail.Studies have found that using a cyclic sulfonimide as a nucleophile and using an iridium catalyzed system to change the mono/diallyl substitution reaction by simply changing the type of base can provide a medium to high yield of monoallylization and diallylated product with excellent stereoselectivity and broad functional group tolerance.In addition,the monoallylated product can be subjected to a second allylation reaction with another molecule of an allyl alcohol derivative.In the third chapter,based on the selective and controllable allylic substitution reaction of cyclic sulfinimine,we further study the allylic substitution reaction of acyclic methylketimine.N-sulfonylmethylketimine was used as the nucleophile,and the transition metal iridium and chiral phosphoramidite ligands were used as the chiral catalytic system.Allyl was obtained with high yield and perfect stereoselectivity.Substitution products.Substrate adaptability studies have shown that this reaction can be applied to imines and allyl carboxylate derivatives substituted with various substituents,showing good substrate tolerance and selectivity.