A Facile, Expeditious Route to the Benzooxabicyclo[3.2.1]octane System. Application to a Short, High-Yield Synthesis of Filiformin
作者:Asok Nath、Jayati Mal、Ramanathapuram V. Venkateswaran
DOI:10.1021/jo952184j
日期:1996.1.1
sequence. Lithium aluminum hydride reduction to the diol 15 followed by acid-catalyzed rearrangement produced benzooxabicyclooctanone (16), arising from exclusive external bond migration. Similarly, ethoxychromone (17) under the same sequence of reactions afforded the homologous bridged ketone 20. For the synthesis of filiformin (1), methoxychromone 24 on ethylene cycloaddition followed by reduction of resultant
已经开发了一种简便有效的途径生成苯并氧杂双环[3.2.1]辛烷体系,并将其用于合成丝纤蛋白(1)。乙烯与甲氧基色酮13的环加成通过串联的环加成和γ-氢提取序列提供了氧杂环丁醇14。氢化铝锂还原为二醇15,然后进行酸催化的重排,产生了苯并氧杂双环辛酮(16),这是由于排他性的外部键迁移引起的。类似地,乙氧基色酮(17)在相同的反应顺序下得到同源的桥联酮20。对于丝状蛋白(1)的合成,在乙烯环加成上的甲氧基色酮24,然后用氢化锂铝提供的二醇10还原所得的氧杂环丁醇25。催化的10重排提供了桥接的酮11,溴化后得到26。