A highly regio- and stereoselective [3 + 2] cycloadditionreaction for constructing novel 3,3′-cyclopentenyldispirooxindoles incorporating two adjacent quaternary spirostereocenters is reported. Under the mild conditions, the asymmetric annulation of isatin-derived MBH carbonates with 3-methyleneoxindoles involving a chiral tertiary amine catalyst provides the corresponding dispirooxindole frameworks
Highly Efficient Enantioselective Construction of Bispirooxindoles Containing Three Stereocenters through an Organocatalytic Cascade Michael-Cyclization Reaction
作者:Hao Wu、Li-Li Zhang、Zhi-Qing Tian、Yao-Dong Huang、Yong-Mei Wang
DOI:10.1002/chem.201203221
日期:2013.1.28
Bispirooxindole derivatives containing three stereocenters, including two spiro quaternary centers, were synthesized in a high‐yielding, atypically rapid, and stereocontrolled cascade Michael–cyclization reaction between methyleneindolinones and isothiocyanato oxindoles catalyzed by a bi‐ or multifunctional organocatalyst. Mild conditions were used to construct bispirooxindoles with excellent enantio‐
Regioselective ring expansion followed by H-shift of 3-ylidene oxindoles: a convenient synthesis of N-substituted/un-substituted pyrrolo[2,3-<i>c</i>] quinolines and marinoquinolines
and metal-free protocol for the synthesis of 4-oxo-4,5-dihydro-3H-pyrrolo[2,3-c]quinolines. The present method under mild reaction conditions with wide functional group compatibility gives several unexplored N-substituted/unsubstituted 4-oxo-4,5-dihydro-3H-pyrrolo[2,3-c]quinolines and marinoquinolines in good to excellent yields. Mechanistic insights for the synthesis of N-substituted pyrroloquinolines
在此,我们报告了一种用于合成 4-oxo-4,5-dihydro-3 H -pyrrolo[2,3 - c ] 喹啉的简单且无金属的方案。本方法在温和的反应条件下具有广泛的官能团相容性,以良好至优异的产率提供了几种未开发的 N-取代/未取代 4-oxo-4,5-dihydro-3 H -pyrrolo [2,3 - c ] 喹啉和 marinoquinolines。N-取代吡咯并喹啉合成的机理研究揭示了 3-亚基氧吲哚的扩环和 H 位移是关键步骤。
Brønsted Base and Lewis Acid Cooperatively Catalyzed Asymmetric <i>exo</i>′-Selective [3 + 2] Cycloaddition of Trifluoromethylated Azomethine Ylides and Methyleneindolinones
作者:Yang Yi、Yuan-Zhao Hua、Hui-Jie Lu、Lan-Tao Liu、Min-Can Wang
DOI:10.1021/acs.orglett.0c00283
日期:2020.4.3
3-dipolar cycloaddition is reported through chiral dinuclear zinc catalysts. An asymmetric exo′-selective [3 + 2] cycloaddition of CF3-containing N-unprotected isatin-derived azomethineylides is realized. In the presence of 10 mol % of catalyst, azomethineylides react efficiently with methyleneindolinones, giving a series of trifluoromethyl-substituted 2,3-pyrrolidinyl dispirooxindoles with highly enantio-