The Palladium-Catalyzed Preparation of Condensed Tetracyclic Heterocycles and their Application to the Synthesis of rac-Mangochinine

Abstract

Dihydroisoquinoline derivatives and their analogues, prepared by the Bischler-Napieralsky reaction, were converted to their indole-fused derivatives. Scope and limitations of the palladium-catalyzed reaction, proceeding through the tautomeric enamine forms of these compounds, were studied and the process was extended to the preparation of racemic mangochinine.