Synthesis of Phthalides and 3,4-Dihydroisocoumarins Using the Palladium-Catalyzed Intramolecular Benzannulation Strategy
作者:Taishi Kawasaki、Shinichi Saito、Yoshinori Yamamoto
DOI:10.1021/jo016336o
日期:2002.4.1
A novel method for the synthesis of phthalides and 3,4-dihydroisocoumarins via the palladium-catalyzed intramolecular benzannulation of bis-enyne and enyne-diyne systems is described. Various kinds of substituted phthalides 9 and 17 and 3,4-dihydroisocoumarins 19 were synthesized from 8, 16, and 18, respectively, in moderate to excellent yields. The benzannulation reaction proceeded chemoselectively
描述了一种新的方法,可通过钯催化双烯炔和烯炔-二炔系统的分子内苯环合成苯二甲酸酯和3,4-二氢异香豆素。分别由8、16和18合成了各种取代的邻苯二甲酸酯9和17以及3,4-二氢异香豆素19,产率中等至优异。苯环化反应进行化学选择,得到相应的稠环化合物A,而没有形成区域异构体产物B(eq 6)。此外,该方法学被应用于生物活性的3-正丁基邻苯二甲酸酯23的合成。