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A catalytic synthesis of selectively substituted phenanthridines is achieved through a reaction sequence involving palladium/norbornene-catalyzed unsymmetrical aryl-aryl and Heck couplings followed by aza-Michael and retro-Mannich reactions. In spite of the many steps involved the method is very simple and allows the formation of selectively substituted phenanthridines under mild conditions in a straightforward one-pot reaction starting from readily available aryl iodides and bromides.

Selectively substituted phenanthridine derivatives are obtained by a facile reaction of o-alkylated aryl iodides, o-bromoarenesulfonylanilines and activated olefins in the presence of palladium and norbornene as catalysts. The reaction takes place under mild conditions to give the products in satisfactory yields using readily available starting materials.

Palladium-catalyzed dehydrogenation of suitable chains bonded to an ortho position of an iodoarene has been achieved by two methods both involving oxidative addition of the iodoarene to palladium(0) and palladacycle formation under mild conditions.