| Aromatic benzoheterocycles are widely present in many natural producrs,pharmaceuticals and bioactive compounds.Besides,the isothiourea-based HBTM,as an efficient organocatalyst,received great attention in the field of asymmetric catalysis.In recent years,organocatalytic asymmetric cascade reactions provided a new poweful and environmentally friendly synthetic method.Based on the review of the development of bifunctional organocatalytic asymmetric cascade reactions,we employed the strategy of dearomatization of benthiazole ring and the asymmetric squaramide catalyzed cycloadditions to building chiral aza-heterocyclic skeletons.The main work include the following two parts:Part one demonstrated an organocatalytic asymmetric Mannich/cylization cascade reaction between 2-benzothiazolimines with azlactones.Through the screening of the catalysts and solvents,this formal[4+2]cyclization could afford the desired adduct in good to high yields and excellent stereoselectivities（up to 99%ee,>20?:?1 dr）.Further exploration of the substrate scope demonstrated that the reaction tolerated a series of substrates with different electronic properties.All products were characterized by 1H NMR,13C NMR,HRMS and HPLC.This reaction provied a new and straightforward synthetic methodology to produce benzothiazolopyrimidinones with highisolated yield and excellent stereocontrol under mild condition.Part two described an organocatalytic asymmetrc domino reaction between benzothiazole ethyl ester with（E）-2-nitro-3-phenylallyl acetate.We examined a series of organocatalysts,solvents,additives and temperatures The substrate scope was determined,and some products were characterized by 1H NMR,13C NMR.and HPLC. |
