A Novel Synthesis of Methylenecyclopropane Spiro-Linked with Cycloalkanes via a Cyclization of Allylic Epoxides and Its Application to a Synthesis of Fused 3-Methylfurans
作者:Tsuyoshi Satoh、Yasushi Kawase、Koji Yamakawa
DOI:10.1246/bcsj.64.1129
日期:1991.4
Ring closure of allylic epoxides derived from 1-chloroalkyl phenyl sulfoxides and cyclic ketones with lithium diisopropylamide (LDA) in 3-Exo-Tet mode gave spiro-linked methylenecyclopropanes having a hydroxyl group in good yields. Oxidation of these compounds gave ketones, which were then treated with p-toluenesulfonic acid in 1,4-dioxane or DMSO at 100°C to give fused 3-methylfurans in good overall
衍生自 1-氯代烷基苯基亚砜和环酮的烯丙基环氧化物与二异丙基氨基锂 (LDA) 在 3-Exo-Tet 模式下闭环得到具有羟基的螺环连接亚甲基环丙烷,收率良好。这些化合物的氧化得到酮,然后在 1,4-二恶烷或 DMSO 中在 100°C 下用对甲苯磺酸处理,以良好的总产率得到稠合的 3-甲基呋喃。该程序适用于从 4-甲基环己酮合成薄荷呋喃。