A Facile Synthesis of 2H-Chromenes and 9-Functionalized Phenanthrenes through Reactions between α,β-Unsaturated Compounds and Arynes
作者:Tiexin Zhang、Xian Huang、and Luling Wu
DOI:10.1002/ejoc.201200042
日期:2012.6
Facile syntheses of 2H-chromenes or 9-functionalized phenanthrenes under mild conditions in moderate to good yields have been developed. They each involve annulations of arynes with α,β-unsaturated compounds bearing different electron-withdrawing groups (EWGs). Depending on the natures of the different EWGs, the reactions proceed by different pathways: enals react with arynes through a tandem [2+2]
已经开发了在温和条件下以中等至良好产率轻松合成 2H-色烯或 9-官能化菲的方法。它们都涉及芳炔与带有不同吸电子基团 (EWG) 的 α,β-不饱和化合物的环化。根据不同 EWG 的性质,反应通过不同途径进行:烯醛与芳炔通过串联 [2+2] 环加成/热电环开环/6e-电环化序列反应得到 2H-色烯,而酰基-/乙氧羰基/氰基取代的苯乙烯与芳烃发生狄尔斯-阿尔德反应,然后芳构化得到9-官能化的菲。已经研究并详细讨论了范围、局限性、区域选择性和机制。