Synthesis of Unsymmetrical Ureas with Coumarin and Thiadiazole Ring Under Microwave Irradiation
作者:Lan-Qin Chai、Hong-Song Zhang、Wen-Kui Dong、Yan-Ling Zhao
DOI:10.1080/10426500903036022
日期:2010.6.30
A series of coumarin-3-yl substituted unsymmetrical ureas were synthesized by the reaction of 3-coumarin isocyanate, which was prepared from 3-coumarinyl azide by Curtius rearrangement, with various aromatic amines, 2-amino-5-phenyl-1,3,4-thiadiazole, and 2-amino-5-aryloxymethylene-1,3,4-thiadiazoles under microwave irradiation. Compared to conventional methods, this synthesis has the advantages of mild reaction conditions, easy handling, and high yields. The products have been characterized by analytical and spectral (IR and 1H NMR) data.