Sigmatropic Dearomatization/Defluorination Strategy for C−F Transformation: Synthesis of Fluorinated Benzofurans from Polyfluorophenols
作者:Koichi Okamoto、Mitsuki Hori、Tomoyuki Yanagi、Kei Murakami、Keisuke Nogi、Hideki Yorimitsu
DOI:10.1002/anie.201809035
日期:2018.10.22
synthesis of fluorinated benzofurans from polyfluorophenols has been accomplished by means of a sigmatropic dearomatization/defluorination strategy composed of three processes: (1) interrupted Pummerer reaction of ketene dithioacetal monoxides with polyfluorophenols followed by [3,3] sigmatropic rearrangement, (2) Zn‐mediated smooth reductive removal of fluoride from the dearomatized intermediate, and
通过以下三种方法组成的σ脱芳香化/脱氟策略可以轻松地从多氟酚合成氟化苯并呋喃:(1)烯酮二硫缩醛一氧化碳与聚氟酚的间断Pummerer反应,然后进行[3,3]σ重排,(2)Zn介导的从脱芳香化中间体中顺利还原还原去除氟化物,以及(3)酸促进的环化/芳香化。机理研究揭示了在本系统中多氟酚的重要特征反应性。一些氟化的苯并呋喃产物是通过利用2-甲基硫烷基部分进行转化的。