An efficient synthesis of quinazoline-2,4-dione derivatives with the aid of a low-valent titanium reagent
作者:Da-Qing Shi、Guo-Lan Dou、Zheng-Yi Li、Sai-Nan Ni、Xiao-Yue Li、Xiang-Shan Wang、Hui Wu、Shun-Jun Ji
DOI:10.1016/j.tet.2007.07.011
日期:2007.9
A facile synthetic method using low-valenttitaniumreagent (TiCl4/Zn system) to promote the novel reductive cyclization of 2-nitrobenzamides and triphosgene is described. Sequentially, a series of quinazoline-2,4-diones were synthesized in good yields.
Synthesis of Quinazolines and Imidazo[1,2-<i>c</i>]quinazolines with the Aid of a Low-Valent Titanium Reagent
作者:Daqing Shi、Juxian Wang、Chunling Shi、Liangce Rong、Qiya Zhuang、Hongwen Hu
DOI:10.1055/s-2004-822893
日期:——
A short and facile synthesis of a series of quinazolines and imidazo[1,2-c]quinazolines was accomplished in good yields via the novel reductive cyclization of 2-nitrobenzyl amines or 2-(2-nitrophenyl)imidazoles with ortho-ester, aldehydes or ketones promoted by TiCl4/Zn system. The structures were established by spectroscopic data and confirmed by X-ray analysis.
A Novel and Efficient Synthesis of 2-Aryl-2<i>H</i>-indazoles via SnCl<sub>2</sub>-Mediated Cyclization of 2-Nitrobenzylamines
作者:Da-Qing Shi、Guo-Lan Dou、Sai-Nan Ni、Jing-Wen Shi、Xiao-Yue Li、Xiang-Shan Wang、Hui Wu、Shun-Jun Ji
DOI:10.1055/s-2007-986665
日期:2007.10
A mild, efficient, and novelsynthesis of 2-aryl-2H-indazoles via cyclization of 2-nitrobenzylamines promoted by SnCl 2 ·2H 2 O has been described. This method applies to a wide scope of substrates containing electron-donating and electron-withdrawing substituents.
描述了通过 SnCl 2 ·2H 2 O 促进的 2-硝基苄胺的环化反应温和、高效、新颖地合成 2-芳基-2H-吲唑。该方法适用于广泛的含有给电子和吸电子取代基的底物。