Highly stereocontrolled synthesis of [3.3.3] propellane sesquiterpenes. ( ± )-Modhephene and (±)-epimodhephene
作者:Heinrich Schostarez、Leo A. Paquette
DOI:10.1016/0040-4020(81)80009-9
日期:1981.1
Stereospecific total synthesis of (±)-modhephene (2) and (±)-epimodhephene (3) are reported. Conjugate addition of 1-trimethylsilyl-1-butyn-4-yl cuprate (BF3-etherate catalysis) to bicyclic ketone 6, fluoride ion-promoted deblocking of the terminal acetylene, and ene reaction, gave tricyclic enone 11. Sequential Wittig methylenation, regiocontrolled epoxidation, and Lewis acid catalyzed isomerization
据报道立体特异性合成了(±)-二苯乙(2)和(±)-表二烯(3)。共轭加成1-三甲基甲硅烷基-1-丁炔-4-基铜酸酯(BF 3-醚酸酯催化)到双环酮6,氟化物离子促进末端乙炔的解封,和烯反应,得到三环烯酮11。连续的维蒂希甲基化,区域控制的环氧化和路易斯酸催化的异构化提供了酮14,其双键重定位和Wolff-Kishner还原仅导致2。在到3的更短路径中,将6的3-丁烯基铜酸酯加到了7上。。发现该中间体的热解,亚甲基化和双键异构化成功地递送了纯3。