Lewis Acid-Catalyzed Conjugate Addition−Cyclization Reactions of Ethenetricarboxylates with Substituted Propargyl Alcohols: Stereoselectivity in the Efficient One-Pot Synthesis of Methylenetetrahydrofurans
作者:Satoshi Morikawa、Shoko Yamazaki、Momoko Tsukada、Suguru Izuhara、Tsumoru Morimoto、Kiyomi Kakiuchi
DOI:10.1021/jo070882l
日期:2007.8.1
propargyl alcohols 4 with ZnBr2 at 80−110 °C led to (Z)-silicon-substituted products stereoselectively. Reaction of 1 and γ-ester-substituted propargyl alcohol 7 in the presence of various Lewis acids gave ester-substituted methylenetetrahydrofurans stereoselectively. Interesting Lewis acid dependency on stereoselectivity for the reaction of 7 was found. Reaction of α-substituted propargyl alcohols
由于含氧杂环系统存在于许多生物活性化合物中,因此它们是有机化学中的重要结构。在这项工作中,研究了路易斯酸催化的乙烯三羧酸酯衍生物1与取代的炔丙醇的环化反应,生成亚甲基四氢呋喃。的反应1和γ-硅取代的炔醇4与ZnBr 2在80-110℃下导致(ż) -硅取代的产品立体选择性。的反应1和γ-酯取代的丙炔醇7在各种路易斯酸存在下,立体选择性地得到酯取代的亚甲基四氢呋喃。发现有趣的路易斯酸对7的反应的立体选择性的依赖性。α-取代的炔丙醇的反应也得到环化产物。