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.
Direct Aza-Darzens Aziridination of<i>N</i>-Tosylimines with 2-Bromomalonates for the Synthesis of Highly Functionalized Donor-Acceptor Aziridines
作者:Xingxing Wu、Lei Li、Junliang Zhang
DOI:10.1002/adsc.201200628
日期:2012.12.14
An approach to highlyfunctionalizeddonor-acceptoraziridines by the aziridination of N-tosylimines and 2-bromomalonates in the presence of sodium hydride under mild conditions has been developed. The high-yielding reaction has a relatively broad scope and can be easily scaled up to the gram level.
A new type of metal-free [5+1] cycloaddition reaction of donor–acceptor aziridines with 2-(2-isocyanoethyl)indoles is reported herein. This method exhibits broad substrate scope and atom-economy. A series of 2H-1,4-oxazines containing an indole heterocycle skeleton were obtained in up to 92% yield under mild reaction conditions. Control experiments revealed that free indole N–H is crucial for the above
本文报道了供体-受体氮丙啶与2-(2-异氰乙基)吲哚的新型无金属[5+1]环加成反应。该方法表现出广泛的底物范围和原子经济性。在温和的反应条件下,得到了一系列含有吲哚杂环骨架的2 H -1,4-恶嗪,收率高达92%。对照实验表明,游离吲哚 N-H 对于上述转化至关重要。理论计算研究为深入了解反应机理提供了指导,并确定了游离吲哚N-H和羰基之间的氢键,以降低过渡态的自由能垒。
Facile iodine(III)-induced oxidative cycloaddition of N-sulfonyl imines with methylene compounds under neutral conditions
作者:Renhua Fan、Linfei Wang、Yang Ye、Jin Zhang
DOI:10.1016/j.tetlet.2009.04.056
日期:2009.7
An efficient oxidative cycloaddition of N-sulfonyl imines with methylene compounds using PhIO with a catalytic amount of KI under neutral conditions, which affords 2,2-difunctionalized aziridines in good to excellent yields, is reported. (c) 2009 Elsevier Ltd. All rights reserved.