Synthesis of Polysubstituted
<i>Meta</i>
‐Halophenols by Anion‐Accelerated 2π‐Electrocyclic Ring Opening
作者:Markus Staudt、Theis Sølling、Lennart Bunch
DOI:10.1002/chem.202100939
日期:2021.7.26
anion-accelerated 2π-electrocyclic ring opening of 6,6-dihalobicyclo[3.1.0]hexan-2-ones at low temperature to give the corresponding meta-halophenols in good to high yields (18 examples, 29–92 % yield, average: 65 %). Many of the phenols have unconventional substitution patterns and are reported here for the first time. Furthermore, the strength of the methodology was shown by the total synthesis of the densely functionalized
旋转 - 热允许 - 2π-电环开环反应需要高温才能进行。在此,我们报告了 6,6-二卤双环 [3.1.0] 己-2-酮在低温下的第一个阴离子加速 2π-电环开环,以良好到高产率得到相应的间卤代苯酚(18 个例子,29 –92 % 的产率,平均:65 %)。许多酚类具有非常规的取代模式,这里是首次报道。此外,该方法的强度通过密集官能化的酚类天然产物卡姆波辛(分离为内酰胺脱水物)的全合成显示出来。在 ab initio 研究中研究了阴离子加速的反应机制,得出的结论是碱介导的质子提取抗同时离开的内溴是直接导致间卤代苯酚的整体协调反应机制中的起始步骤。