Y(OTf)3-Catalyzed Diastereoselective [3+2] Cycloaddition of N-Tosylaziridines and Imines; Efficient Synthesis of Multisubstituted Imidazolidines
作者:Junliang Zhang、Xingxing Wu
DOI:10.1055/s-0031-1290816
日期:2012.7
Abstract An efficient Y(OTf)3-catalyzed generation of azomethine ylides from donor–acceptor aziridines and their [3+2] cycloaddition with imines was developed. The method provides facile access to multisubstituted imidazolidines, which have been extensively used in organic synthesis. Furthermore, a three-component reaction on a gram scale and an asymmetric variation were also developed in this work
Lewis Acid-catalyzed [3 + 2]Cyclo-addition of Alkynes with<i>N</i>-Tosyl-aziridines via Carbon–Carbon Bond Cleavage: Synthesis of Highly Substituted 3-Pyrrolines
作者:Lei Li、Junliang Zhang
DOI:10.1021/ol202603e
日期:2011.11.18
A novel, efficient, and highly regioselective Lewis acid-catalyzed [3 + 2] cycloaddition of alkynes with azomethine ylides, which are easily obtained from N-tosylaziridines via C–C bond heterolysis at room temperature was developed. Moderate enantioselectivity (70% ee) can be achieved by the application of the commercially available chiral Pybox 7 as the ligand.
Construction of thiazines and oxathianes via [3 + 3] annulation of N-tosylaziridinedicarboxylates and oxiranes with 1,4-dithiane-2,5-diol: application towards the synthesis of bioactive molecules
作者:Rohit Kumar Varshnaya、Prabal Banerjee
DOI:10.1039/c7ob00941k
日期:——
Lewis acid catalyzed [3+3] annulation of N tosylaziridinedicarboxylates and oxiranes with in situ generated mercaptoaldehyde for the synthesis of functionalized thiazine and oxathiane derivatives has been developed. Additionally, this method facilitate the derivatization of thiazine by detosylation and Krapcho monodecarboxylation.
A novel early and late transition-metal relay catalysis has been developed by combining a gold-catalyzedcycloisomerization and a Yb(OTf)3-catalyzed diastereoselective [3 + 2] cycloaddition with aziridines in a selective C–C bond cleavage mode. Various biologically significant complex nitrogen-containing spiro heterocycles were rapidly constructed from readily available starting materials under mild
Synthesis of polycyclic spiroindolines <i>via</i> the cascade reaction of 3-(2-isocyanoethyl)indoles
作者:Haizhen Li、Jinyu Wu、Jianfeng Zheng、Wei-Dong Z. Li
DOI:10.1039/d1cc04576h
日期:——
Tandem reactions of the yttrium(iii) catalyzed ring-opening reaction of 2,2′-diester aziridines with 3-(2-isocyanoethyl)indoles and the subsequent Friedel–Crafts/Mannich/desulfonylation were reported. A series of polycyclic spiroindolines containing tetrahydro-β-carbolines were obtained in moderate to excellent yields (56–92%) in one step under mild reaction conditions. A possible catalytic mechanism
报道了钇 ( iii ) 催化 2,2'-二酯氮丙啶与 3-(2-异氰乙基) 吲哚的开环反应和随后的 Friedel-Crafts/Mannich/脱磺酰化反应的串联反应。在温和的反应条件下,一步获得了一系列含有四氢-β-咔啉的多环螺二氢吲哚,收率中等至极好(56-92%)。还提出了可能的催化机制。