Stereochemical course of the modified polonovski reaction and mercuric acetate oxidation in the preparation of 2-substituted 1,2,3,4,6,7,12,12b-octahydroindolo[2, 3-a]quinolizines
作者:Mauri Lounasmaa、Esko Karvinen
DOI:10.1016/s0040-4020(01)86565-0
日期:1991.8
H2O2 oxidation of C(4) monosubstituted 1-[2-(3-indolyl)ethyl]-piperidines 7a, 7b and 7c followed by the modified Polonovski reaction yielded exclusively indolo[2,3-a]quinolizidines 4a, 4b and 4c possessing the C(12b)H-C(2)Htrans-relationship. The same piperidines, when subjected to the Fujii modification of the mercuric acetate oxidation followed by NaBH2 reduction (the Fujii procedure), gave nearly
C(4)单取代的1- [2-(3-吲哚基)乙基]-哌啶7a,7b和7c的H 2 O 2氧化,然后经过修饰的Polonovski反应,仅生成吲哚并[2,3-a]喹喔啉4a,4b和具有C(12b)HC(2)Htrans关系的4c。相同的哌啶在进行乙酸汞氧化的藤井修饰后再用NaBH 2进行修饰还原(Fujii方法),几乎只得到了具有C(12b)HC(2)H顺式关系的吲哚[2,Ja]喹唑烷3a,3b和3c。4-甲基-1- [2-(3-吲哚基)乙基]-哌啶7a的“经典”乙酸汞氧化,主要产生具有C(12b)HC(2)的吲哚[2,3-a]喹唑烷4a。 H反式关系以及其他异构体3a的数量取决于后处理程序(有或没有NaBH 4还原)。