A simple and expedient method for the stepwise synthesis of 2-ethoxy-(4H)-3,1-benzoxazine-4-ones
作者:Asrin Bahmani、Mahnaz Sharafi-Kolkeshvandi、Farzad Nikpour
DOI:10.1016/j.cclet.2012.01.028
日期:2012.4
A simple and practical route is described for the synthesis of 2-ethoxy-(4H)-3,1-benzoxazine-4-ones using the coupling reaction of anthranilic acid derivatives with diethyl dicarbonate following with fast cyclization of the carbamate adduct with a dehydrocyclization agent such as cyanuric chloride and N,N′-dicyclohexylcarbodiimide in PEG at room temperature. High yields of the products obtained under
描述了一种简单实用的路线,可通过邻氨基苯甲酸衍生物与碳酸二乙酯的偶合反应,然后氨基甲酸酯加合物与环戊二酸酯快速环化,合成2-乙氧基-((4 H)-3,1-苯并恶嗪-4-酮。室温下,在PEG中使用氰尿酰氯和N,N'-二环己基碳二亚胺等脱氢环化剂。在温和的反应条件下,只需对反应混合物进行简单的后处理,即可获得高收率的产品。