作者:Stefano Serra、Claudio Fuganti
DOI:10.1055/s-2005-863741
日期:——
A new regioselective pathway to substituted carbazole derivatives is described here. According to this procedure substituted 2-alkoxycarbonyl-4-acetoxy-9-(p-toluenesulfonyl) carbazoles are obtained by treatment of substituted 6-[2-(p-toluenesulfonylamino)-aryl]-3-alkoxycarbonylhex-3-en-5-ynoic acids with acetic anhydride in the presence of sodium acetate. The latter acids are prepared from the easily available substituted o-iodo-anilines by Sonogashira coupling with propargylic alcohol and Wittig reaction as the key steps. The described benzannulation reaction proceeds in regiospecific fashion and a range of substituents are tolerated.
这里描述了一种新型的区域选择性合成取代咔唑衍生物的方法。根据该程序,通过将取代的6-[2-(对甲苯磺酰胺)-芳基]-3-烷氧羧基己-3-烯-5-炔酸与醋酸酐在醋酸钠存在下处理,可以获得取代的2-烷氧羧基-4-醋氧基-9-(对甲苯磺酰基)咔唑。后者的酸是通过与炔醇进行Sonogashira偶联和Wittig反应这两个关键步骤,从易得的取代o-碘苯胺制备而成。所描述的苯环轧制反应是以区域特异性的方式进行的,并且可以容忍多种取代基。