Tandem Palladium/Copper-Catalyzed Decarboxylative Approach to Benzoimidazo- and Imidazophenanthridine Skeletons.

A protocol for a tandem Pd/Cu-catalyzed intermolecular cross-coupling cascade between o -bromobenzoic acids and 2-(2-bromoaryl)-1 H -benzo[ d ]imidazoles or the corresponding imidazoles is presented. The protocol provides conceptually novel and controlled access to synthetically useful N -fused (benzo)imidazophenanthridine scaffolds with high efficiency, a broad substrate scope, and excellent functional group compatibility.