A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjuga...A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjugate addition-protonation products bearing 1,3-O-heterotertiary-O-heteroquarternary nonadjacent stereocenters were obtained in excellent yields,moderate to good diastereoselectivities,and excellent enantioselectivities (up to 97% yield,11:1 dr,and 98% ee).Induction by 2,2'-biphenol could effectively promote the production of the corresponding diastereoisomers via cycloaddition intermedia.展开更多
基金This work was supported by the National Natural Science Foundation of China (U1804283)the National Postdoctoral Pro-gram for Innovative Talents (No. BX201700071)+1 种基金a project funded by the China Postdoctoral Science Foundation (No. 2017M622348)the 111 project (D17007).
文摘A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjugate addition-protonation products bearing 1,3-O-heterotertiary-O-heteroquarternary nonadjacent stereocenters were obtained in excellent yields,moderate to good diastereoselectivities,and excellent enantioselectivities (up to 97% yield,11:1 dr,and 98% ee).Induction by 2,2'-biphenol could effectively promote the production of the corresponding diastereoisomers via cycloaddition intermedia.