Domino Carbocationic Cyclization of Functionalized Cyclopropyl Ketones: Facile One-Pot Access to Peri- and Angularly Fused Polycyclic Aromatic and Heteroaromatic Frameworks
作者:Sukumar Nandi、U. K. Syam Kumar、Hiriyakkanavar Ila、Hiriyakkanavar Junjappa
DOI:10.1021/jo020230r
日期:2002.7.1
yields in a one-pot operation. The methodology provides efficient, high-yield routes for synthesis of novel substituted dihydrophenalenes, dihydrobenzo[d,e]anthracene, cyclopenta[a]naphthalene, and fused heteroaromatics such as substituted 4,5-dihydrobenzo[c,d]indole, dihydronaphtho[1,8-b,c]thiophene, dihydroindeno[5,4-b]- and -[4,5-b]-thiophenes, cyclopenta[a]carbazole, and dihydrocyclopenta[e]indazol-3-one
已显示通过碱诱导的各种芳基/杂芳基乙腈与1-(2-芳基环丙基)-3,3-(双甲硫基)-2-丙烯-1-酮的1,4-加成消除反应得到的共轭加合物很容易合成一锅操作中,酸诱导的多米诺碳正离子重排可高产率产生各种取代的三环芳族和杂芳族骨架。该方法为合成新型取代的二氢菲咯啉,二氢苯并[d,e]蒽,环戊[a]萘和稠合的杂芳族化合物(例如取代的4,5-二氢苯并[c,d]吲哚,二氢萘[])提供了有效的高产率途径。 1,8-b,c]噻吩,二氢茚并[5,4-b]-和-[4,5-b]噻吩,环戊[a]咔唑和二氢环戊[e]吲唑-3-one衍生物。这种有趣的多米诺骨牌过程的可能机理似乎涉及逐步或伴随的酸诱导的开环和环丙基酮的分子内环缩合反应,从而生成带有反应性苄基碳正离子的苯并稠合的芳烃(或杂芳烃)中间体,该中间体被预先存在的芳香族分子内捕获(或杂芳族)环或新形成的苯环,分别得到周边稠合或成角度稠合的产物。因此,整个