作者:Reinhold Zimmer、Hans-Ulrich Reißig
DOI:10.1055/s-1989-27428
日期:——
Nucleophilic Substitution of 6H-1,2-Oxazines via Azapyrylium Ions In the presence of Lewis-acids, the 6-methoxy group of 6-methoxy-6H-1,2-oxazines is smoothly substituted by nucleophiles to give a variety of new 6-substituted 6H-1,2-oxazines. Azapyrylium ions (1,2-oxazin-1-ium ions) are suggested to be the intermediates involved in this regioselective reaction which proceeds most satisfactoryly with silylated compounds or electron-rich arenes as nucleophilic components.
通过氮杂吡喃鎓离子对 6H-1,2-噁嗪进行亲核取代 在路易斯酸存在的情况下,6-甲氧基-6H-1,2-噁嗪的 6-甲氧基基团会被亲核物顺利取代,生成各种新的 6-取代型 6H-1,2-噁嗪。据推测,氮丙啶离子(1,2-噁嗪-1-鎓离子)是参与这种区域选择性反应的中间体,这种反应在硅烷化化合物或富含电子的炔类化合物作为亲核组分的情况下进行得最为顺利。