The synthesis of pyrazolotetrazepin-7-ones from 1,3,5-triazinanes with N,N′-cyclic azomethine imines was achieved via a formal (5 + 2) pathway under thermal conditions. The annulation reaction is catalyst-free and additive-free.
Copper(II)-Catalyzed Asymmetric 1,3-Dipolar [3+4] Cycloaddition and Kinetic Resolution of Azomethine Imines with Azoalkenes
作者:Liang Wei、Zuo-Fei Wang、Lu Yao、Guofu Qiu、Haiyan Tao、Hua Li、Chun-Jiang Wang
DOI:10.1002/adsc.201600961
日期:2016.12.22
copper(II)‐catalyzedenantioselective 1,3‐dipolar [3+4] cycloaddition of azomethineimines with in situ formed azoalkenes has been realized. This strategy provides a facile access to biologically important 1,2,4,5‐tetrazepine derivatives in high yield with exclusive regioselectivity and high stereoselectivity. Moreover, enantioenriched azomethineimines could be obtained via an efficient kinetic resolution
<i>N</i>-Heterocyclic Carbene-Catalyzed [3+4] Cycloaddition and Kinetic Resolution of Azomethine Imines
作者:Ming Wang、Zhijian Huang、Jianfeng Xu、Yonggui Robin Chi
DOI:10.1021/ja411110f
日期:2014.1.29
[3+4] cycloaddition of azomethineimines and enals is disclosed. Oxidative catalytic remote activation of enals affords 1,4-dipolarophile intermediates that react with 1,3-dipolarazomethineimines to generate dinitrogen-fused seven-membered heterocyclic products with high optical purities. Our approach also provides effective kinetic resolution of azomethineimines, in which the substrate chiral center