作者:Liming Zhang、Masato Koreeda
DOI:10.1021/ol026739q
日期:2002.10.1
(+/-)-Kelsoene (4) has been synthesized from 2,5-dihydroanisole in 16 steps in 12.5% overall yield. The key step involves a base-catalyzed reaction of gamma-keto tosylate (5), which effects a homo-Favorskii rearrangement to 16 as well as the corresponding intramolecular S(N)2 product 15 from the enolate of 5. Ketone 15 can efficiently be isomerized to cyclobutanone 17 having the kelsoene carbon skeleton
[反应:见正文](+/-)-煤油(4)是由2,5-二氢茴香醚分16步合成的,总收率为12.5%。关键步骤涉及γ-酮基甲苯磺酸酯(5)的碱催化反应,该反应会引起均-Favorskii重排至16,以及相应的分子内S(N)2产物15的烯醇化物15。酮15可以有效在酸处理后被异构化为具有煤油碳骨架的环丁酮17。