Organocatalytic Asymmetric Synthesis Of Nitro-methanobenzo[7]Annulenes And Spirocyclic Tetrahydrothiophenes

At the beginning of 21 st,due to the pioneering work of List,MacMillan and Jacobsen,plenteous achievements have been reached in organocatalytic.In organocatalysis,asymmetric tandem reactions play an important role for the synthesis of complex multi-chiral compounds.Organic bifunctional catalysts have been widely used in asymmetric tandem reactions due to its unique role.In this paper,we using organic bifunctional catalysts for asymmetric synthesis of Nitro-Methanobenzo[7]Annulenes and Spirocyclic Tetrahydrothiophenes.In the first chapter,we introduced the application of organic bifunctional catalysts in asymmetric tandem reactions and summarized the synthesis progress of the bicyclic[3.2.1]octanes in recent years.In the second chapter,we introduced a synthesis of nitro-methanobenzo[7]annulenes which containing bicyclic[3.2.1]octanes by bifunctional thiourea catalyzed Michael-Aldol [3+2] cycloaddition reaction.The bicyclo[3.2.1]octanes-containg nitro-methanobenzo[7]annulenes have been efficiently synthesized by the quinine-derived indene thiourea catalyst using prepared 2-alkyl-3-hydroxynaphthalene-1,4-dione and nitroolefins.In the third chapter,we introduced a [3+2] annulation reaction for synthesis of spiro-tetrahydrothiophene derivatives by bifunctional catalyst using thiophenone and saccharin-derived unsaturated imines.