A New Approach to the Nazarov Reaction via Sequential Electrocyclic Ring Opening and Ring Closure
作者:Tina N. Grant、F. G. West
DOI:10.1021/ja063421a
日期:2006.7.1
furnishes vinylcyclopropanol silyl ethers in good yield. Treatment with silver(I) at room temperature effects disrotatory electrocyclic opening to a 2-chloro-3-silyloxypentadienyl cation, which then undergoes conrotatory (Nazarov) electrocyclization to provide chlorocyclopentenones. This two-step sequence offers a convenient and mild alternative to the standard Nazarov cyclization protocol via a formal 4+1
2-甲硅烷氧基二烯的区域选择性二氯环丙烷化以良好的收率提供乙烯基环丙醇甲硅烷基醚。在室温下用银 (I) 处理会导致旋转电环开环成 2-氯-3-甲硅烷氧基戊二烯基阳离子,然后进行旋转(纳扎罗夫)电环化以提供氯环戊烯酮。这种两步序列通过正式的 4+1 结构为标准 Nazarov 环化方案提供了一种方便且温和的替代方案,并提供含有有用卤素官能团的产品。在一个具有苯基侧基的情况下,观察到生成苯甲茚酮的纳扎罗夫反应中断。