Synthesis of 6H-isoindolo[2,1- a]indol-6-ones via Pd-catalyzed cycloaminocarbonylation of 2-(1H-indol-2-yl)phenyl tosylates with CO

摘要

AbstractAn efficient method for preparation of substituted 6H-isoindolo[2,1-a]indol-6-ones (2) that are important structural components of a vast array of naturally occurring and pharmacologically active compounds, has been developed by the palladium-catalyzed intramolecular cycloaminocarbonylation of2-(1H-indol-2-yl)phenyl tosylates with CO. Significantly, the intermolecular aminocarbonylation products2-(1H-indol-2-yl)benzamides are formed when an excess of amine is used in this reaction system. Alternatively,2-(1H-indol-2-yl)benzamides can also be synthesized by the in situ aminolysis of2. Furthermore, treatment of2with hydrosilane in the presence of KOH gave the unprecedented reducing products2-(-1H-indol-2-yl)benzyl alcohols in 75–86% yields. These results demonstrate that 6H-isoindolo[2,1-a]indol-6-ones are versatile substrates for further synthetic elaboration.Graphical abstractDisplay Omitted]]>