The Design And Synthesis Of Chiral Thiazolium NHC Catalysts Bearing C2-Symmetric Chiral Aniline

As a kind of classical biomimetic organocatalysis,N-Heterocyclic Carbene plays an important role in the field of organic chemistry.In recent years,the field of the chiral NHeterocyclic Carbene has attracted much attention,showing broad application prospects.However,there are few studies on the development and application of the chiral thiazolium NHC catalysts.The first chapter of this paper mainly described the development of the chiral NHeterocyclic Carbene.Few examples were reported on the application of the chiral thiazolium NHC catalysts.The main reason might be that there are few chiral skeletons involved in the construction of the chiral thiazolium NHC catalysts.On the other hand,the chiral anilines,bearing C2 axial symmetry,as a kind of excellent chiral block,had shown unique advantages in the construction of chiral imidazole NHC catalysts.The imidazole NHC catalysts could be compatible with transition metals,such as palladium,copper,nickel,etc,to achieve many asymmetric reactions.The second chapter of this paper was mainly about the synthesis of thiazolium NHC catalysts,containing racemic and chiral catalysts.Firstly,about the synthesis of racemic thiazolium NHC catalysts,we modified the thiazole framework by replacing of the simple starting materials,which were included aromatic amines bearing different substituent,alkyl amines,and different cyclic ketones.Then,we also modified from the intermediate of NHC.Subsequently,about the synthesis of the chiral thiazolium NHC catalysts,we mainly used C2 axisymmetric anilines.And we had transformed and optimized the synthesis process.In addition,we also modified the thiazole framework by replacing of other chiral amines and chiral cyclic ketones.The third chapter of this paper is to verify the catalytic activity of the newly chiral thiazolium NHC catalysts,though the screening and optimization of model reaction conditions.And it can catalyze both polar and radical reactions to afford target products in good yield with moderate stereoselectivity.