Versatile Synthesis of Isoquinolines and Isochromenes by Pd-Catalyzed Oxidative Carbonylation of (2-Alkynyl)benzylideneamine Derivatives
作者:Bartolo Gabriele、Lucia Veltri、Vito Maltese、Rosella Spina、Raffaella Mancuso、Giuseppe Salerno
DOI:10.1002/ejoc.201100739
日期:2011.10
heterocyclization/alkoxycarbonylation of readily available (2-alkynylbenzylidene)amine derivatives. In particular, (2-alkynylbenzylidene)(tert-butyl)amines 2 selectively afforded isoquinoline derivatives 3 by N-cyclization, whereas N-(2-alkynylbenzylidene)-N′-phenylhydrazines 5 led to the formation of isochromenes 4 through O-cyclization ensuing from water attack on the imino group of the substrate
异喹啉-4-羧酸酯 3 和异色烯-4-羧酸酯 4 可以通过容易获得的(2-炔基亚苄基)胺衍生物的直接 PdI2 催化氧化杂环化/烷氧基羰基化方便地制备。特别地,(2-炔基苯亚甲基)(叔丁基)胺2通过N-环化选择性地提供异喹啉衍生物3,而N-(2-炔基苯亚甲基)-N'-苯肼5通过O-环化导致异色烯4的形成由水侵蚀基材的亚氨基而引起。在 80–100 °C 和 20–80 atm(25 °C)的 CO/空气 4:1 混合物的醇溶剂中,在 PdI2(2–10 mol-%)存在下进行反应结合 KI(KI/PdI2 摩尔比 = 10)。在亚胺2的情况下,使用脱水剂,例如原甲酸三烷基酯,