An unprecedented TfOH-promoted tandem ring-closure-aryl-migration of 2′-amino chalcone epoxide leading to 3-aryl-4(1H)-quinolones (azaisoflavones) was achieved. The outcome of the reaction was confirmed by NMR analysis and rationalized through the intermediacy of a phenonium ion. This synthetic protocol furnishes azaisoflavones straightforwardly from simple starting materials under mild conditions.
在 TfOH 的促进下,2′-
氨基
查尔酮环氧化物发生了前所未有的
串联环闭-芳基迁移反应,生成了 3-芳基-4(1H)-
喹啉酮(
氮杂异
黄酮)。核磁共振分析证实了反应的结果,并通过
酚离子的中间产物使反应合理化。该合成方案可在温和的条件下从简单的起始原料直接获得偶
氮异
黄酮。