Highly Efficient Hydrogen-Bonding Catalysis of the Diels–Alder Reaction of 3-Vinylindoles and Methyleneindolinones Provides Carbazolespirooxindole Skeletons
作者:Bin Tan、Gloria Hernández-Torres、Carlos F. Barbas
DOI:10.1021/ja203812h
日期:2011.8.17
Carbazolespirooxindole derivatives were synthesized in a high-yielding, atypically rapid, stereocontrolled Diels-Alderreaction catalyzed by a C(2)-symmetric bisthiourea organocatalyst. Simple precursors and mild conditions were used to construct carbazolespirooxindole derivatives with high enantiopurity and structural diversity under H-bonding catalysis. The practical approach recycles the organocatalyst
The enantioselective construction of five-membered spirocyclic oxindoles via a double Michael cascade reaction is described by using dipeptide-based multifunctional quaternary phosphonium salt catalysts. The desired products were obtained in excellent yields (up to 94%) and good to high stereoselectivities (up to >19:1 dr and 99% ee).
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
An efficiently stereoselective [4 + 2] cycloaddition of 3-alkylenyloxindoles and α-diazoketones through sequential visible-light photoactivation and N-heterocycliccarbenecatalysis was achieved. A series of tetrahydropyrano[2,3-b]indoles with an all-carbon quaternary stereocenter were obtained in good yields with excellent diastereo- and enantioselectivities.
通过顺序可见光光活化和N-杂环卡宾催化,实现了3-亚烷基氧吲哚和α-重氮酮的高效立体选择性[4 + 2]环加成反应。以高收率获得了一系列具有全碳四元立体中心的四氢吡喃并[2,3- b ]吲哚,并具有优异的非对映选择性和对映选择性。
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