alkylation–hemiketalization–lactonization cascade of electron-rich hydroxy arenes and distinctively functionalized unsaturated 4-keto esters is developed for the construction of polycyclic bridged 2-chromanol lactones. Following this simple and facile protocol, a broad range of products was prepared in good to excellent yields as a single diastereomer. An unusual conglomerate (enantiomerically pure polymorph) of
富电子的羟基
芳烃和独特官能化的不饱和4-
酮酯的空前的Fe(III)催化的Friedel-Crafts烷基化-半缩
水化-内酯化级联反应被用于构建多环桥联的2-苯并二氢色内酯内酯。遵循此简单而简便的方案,以单一非对映异构体的形式制备了多种产品,收率良好至优异。据报道,3ac具有不寻常的团聚体(对映体纯的多晶型物)和绝对立体
化学,其余产物通过单晶X射线分析和类比得到了严格确认。