Reactions of 5,8-dichloro-2,3-dicyanoquinoxaline with amines and hydrazines. A new and efficient synthetic approach to 3-amino-5,8-dichloroflavazoles
作者:Antonio Guirado、José I. López Sánchez、Delia Bautista
DOI:10.1016/j.tet.2011.03.104
日期:2011.6
Reactions of 5,8-dichloro-2,3-dicyanoquinoxaline with primary amines and hydrazines under different experimental conditions were investigated. Alkylamines provided novel 3-alkylamino-5,8-dichloro-2-cyanoquinoxalines and N-alkyl-(5,8-dichloro-3-alkylamino-2-quinoxalinyl)carboxamidines in high yields. Alkylhydrazines and lithium arylhydrazinides gave previously unattainable 1-alkyl-3-amino-5,8-dichloroflavazoles
研究了5,8-二氯-2,3-二氰基喹喔啉与伯胺和肼在不同实验条件下的反应。烷基胺以高收率提供了新颖的3-烷基氨基-5,8-二氯-2-氰基喹喔啉和N-烷基-(5,8-二氯-3-烷基氨基-2-喹喔啉基)羧am 。烷基肼和芳基肼化锂可提供以前无法获得的1-烷基-3-氨基-5,8-二氯黄酮和3-氨基-1-芳基-5,8-二氯黄酮,其收率良好,接近定量,其分子结构已通过X射线晶体学证实的3- [ N,N-双(4-氯苯甲酰基)氨基] -5,8-二氯-1-苯基黄唑。与肼反应,定量得到5,8-二氯-3-肼基-2-喹喔啉基羧酰胺dra酮,通过热解工艺,高产率地将其转化为此类黄酮的母体化合物3-氨基-5,8-二氯黄酮。肼的损失。