| Chiral nitrogen heterocyclic frameworks are widely exist in active pharmaceuticals and natural products,among which alkaloids containing indole skeletons are one of the important branches of them.Among these compounds,nitrogenous containing structural fragments play an important role in their biological and catalytic activities,especially widely used in the development of chiral drugs,asymmetric catalysis and total synthesis of natural products.Therefore,it has always been one of the hot fields of synthetic chemistry research to explore the ideal synthesis method to construct "chiral nitrogen heterocyclic compound molecular library" quickly and efficiently.In recent ten years,asymmetric ring-opening and cycloaddition reactions of 1,2,3-triazoles,1,2,3,4-tetrazoles and benzotriazones catalyzed by transition metals have been used as a favorable tool for the construction of chiral nitrogen heterocyclic compounds,and have entered a period of rapid development.However,benzotriazoles,as a class of easily accessible aza three-carbon synthons,which are rarely used in asymmetric cycloadditions due to their inherent thermodynamic stability and compatibility issues with phosphine ligands.Hence,the development of ring-opening asymmetric cycloaddition reactions involving benzotriazoles is still of great significance.In this treatise,we reported the first asymmetric tandem denitrogenative palladiumcatalyzed Heck/Tsuji-Trost reaction of benzotriazoles with 1,3-dienes using the chiral tert-butylsulfonamide phosphonate ligands(Sadphos)developed by our group.With high enantioselectivity and high yields of chiral benzohexahydrocarbazole and dihydroindole derivatives(up to 99% yields and up to 99% enantioselectivity).It is worth mentioning that using the same absolute configuration of ligands,pairs of enantiomer isomers can be obtained by changing the electrical properties of the Sadphos parent ring skeleton and phosphine. |
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