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。