The Divergent Cascade Reactions of Arylalkynols with Homopropargylic Amines or Electron-Deficient Olefins: Access to the Spiro-Isobenzofuran-<i>b</i>-pyrroloquinolines or Bridged-Isobenzofuran Polycycles
作者:Lun Wang、Lingyan Liu、Weixing Chang、Jing Li
DOI:10.1021/acs.joc.8b00691
日期:2018.8.3
Two divergent cascade reactions of arylalkynols with homopropargylic amines or electron-deficient olefins were developed to synthesize the spiro-isobenzofuran-b-pyrroloquinolines or bridged-isobenzofuran heterocycles in good yields, respectively. One reaction actually involved intramolecular 5-endo-dig hydroamination cyclization–protonation of homopropargylic amines to give cycloiminium ions and intramolecular
研究了芳基炔醇与均炔丙基胺或缺电子烯烃的两个发散级联反应,分别以高收率合成了螺-异苯并呋喃-b-吡咯并喹啉或桥-异苯并呋喃杂环。一个反应实际上涉及分子内5-内挖加氢胺化环化-均炔丙基胺的质子化反应得到环亚胺离子和分子内5-外挖加氢烷氧基化芳基炔醇的环化反应生成带有外环双键的异苯并呋喃,然后在反应中进行非典型的Povarov型反应PtCl 2 / FeCl 3的存在助催化剂。另一个经历了炔醇的分子内加氢烷氧基化环异构化,随后与亲二烯体正常[4 + 2] cycoaddition。在本文中,芳基炔醇既充当“被掩蔽的”富电子的烯烃又充当“被掩蔽的”富电子的二烯。