A Highly Stereoselective Synthesis of (<i>E</i>)-Enol Lactones by the Wittig Reaction of Cyclic Anhydrides with (α-Alkoxycarbonylethylidene)triphenylphosphorane
作者:Sadao Tsuboi、Hirohumi Fukumoto、Hiroshi Wada、Akira Takeda、Keiichi Fukuyama
DOI:10.1246/bcsj.60.689
日期:1987.2
crystallographic analysis. The reaction of adipic anhydride with 2a afforded 7-ethoxycarbonyl-5-octen-6-olide, 7-ethoxycarbonyl-5,6-octadienoic acid, and (4E, 6E)-7-ethoxycarbonyl-4,6-octadienoic acid. A treatment of nonanedioic anhydride with 2a gave 10-ethoxycarbonyl-8,9-undecadienoic acid, (7E,9E)-10-ethoxycarbonyl-7,9-undecadienoic acid, and diethyl 2-methyl-2,4-undecadienedioate in low yields.
戊二酸酐和甲基或苯基取代的酸酐与(α-烷氧基羰基亚乙基)三苯基正膦(2a,乙氧基;2b,叔丁氧基)反应得到相应的 6-烷氧基羰基-5-庚烯-5-内酯(3)和 6-烷氧基羰基-4-hepten-5-olides 的产率很高。反应高度立体选择性地进行,得到(E)-3。3 的立体化学是通过 X 射线晶体学分析确定的。己二酸酐与 2a 反应得到 7-ethoxycarbonyl-5-octen-6-olide、7-ethoxycarbonyl-5,6-octadienoic acid 和 (4E, 6E)-7-ethoxycarbonyl-4,6-octadienoic acid。用 2a 处理壬二酸酐以低收率得到 10-乙氧基羰基-8,9-十一二烯酸、(7E,9E)-10-乙氧基羰基-7,9-十一二烯酸和 2-甲基-2,4-十一二烯二酸二乙酯.