The bicyclo [2.1.0] Pentane way to the diquinane alcohol part of natural triquinanes. A high yield access starting from trimethylsilyloxycyclopentene.
作者:Michel Franck-Neumann、Michel Miesch、Laurence Gross
DOI:10.1016/s0040-4039(00)97796-7
日期:1990.1
Trimethylsilyloxycyclopentene reacts exclusively with ethyl propiolate in the presence of ZrCl4 to give a [2+2] adduct (alcohol 6, 90 %). After protection, the stereoselective cyclopropanation via 1,3-dipolar addition of 2-diazopropane followed by sensitized photocleavage, leads with good yields to the bicyclo [2.1.0] pentane derivative 11. By deprotection and solvolytic cleavage with dilute mineral
Trimethylsilyloxycyclopentene与的ZrCl存在丙炔酸乙酯反应只4,得到[2 + 2]加成物(醇6,90%)。保护后,通过1,3-偶极2-重氮丙烷的加成反应,然后进行敏化的光裂解的立体选择性环丙烷化,以良好的收率导致了双环[2.1.0]戊烷衍生物11。通过去保护和用稀无机酸的溶剂分解,可以定量和立体地获得二喹烷醇5。