Asymmetric Synthesis of Spirocyclic Oxindole-Fused Tetrahydrothiophenes<i>via N,N′-</i>Dioxide-Nickel(II) Catalyzed Domino Reaction of 1,4-Dithiane-2,5-diol with 3-Alkenyloxindoles
A highly efficient chiral N,N′‐dioxide–nickel(II) complex system has been developed to catalyze the domino thia‐Michael/aldol reaction of 1,4‐dithiane‐2,5‐diol with 3‐alkenyloxindoles. A series of the desired spirocyclic oxindole‐fused tetrahydrothiophenes was obtained in good yields with excellent ee and dr (up to 97% yield, 98% ee, >19:1 dr). Besides, based on the X‐ray crystal structure of the catalyst
Highly Efficient and Stereoselective Construction of Bispirooxindole Derivatives via a Three-Component 1,3-Dipolar Cycloaddition Reaction
作者:Qin Xu、De Wang、Yin Wei、Min Shi
DOI:10.1002/open.201402003
日期:2014.6
A highly regio‐ and stereoselective synthesis of bispirooxindoles by 1,3‐dipolar cycloaddition of in situ generated azomethine ylides from isatin and proline to different electron‐deficient alkenes has been developed. The synthesis affords the desired bispiro scaffold compounds in excellent yields with high regioselectivity under mild conditions. The stereochemistry was determined by single‐crystal
Base Catalyzed Abnormal [3 + 2]-Cycloaddition between Isatin <i>N</i>,<i>N</i>′-Cyclic Azomethine Imine 1,3-Dipole and 3-Methyleneoxindole for the One-Step Construction of Tetracyclic Bispirooxindoles
作者:Xiang-Jia Song、Hong-Xia Ren、Min Xiang、Chen-Yi Li、Fang Tian、Li-Xin Wang
DOI:10.1021/acs.joc.9b03050
日期:2020.3.6
An abnormal [3 + 2]-cycloaddition and highly effective and convenient one-step preparation of tetracyclic bispirooxindoles containing two all-carbon quaternary spirocenters fromisatin N,N'-cyclic azomethine imine 1,3-dipole and 3-methyleneoxindole in the presence of catalytic organic base has been disclosed. A variety of bispirooxindoles bearing a dinitrogen heterocycle with four adjacent cycles have