Synthesis of Phenanthridinones by Palladium-Catalyzed Cyclization of N-Aryl-2-aminopyridines with 2-Iodobenzoic Acids in Water

The first Pd-catalyzed cyclization of N -aryl-2-aminopyridines with 2-iodobenzoic acids for the synthesis of phenanthridinones through C-H bond activation under very low catalyst loadings (down to 0.1 mol% Pd) in water is reported. This protocol features a broad substrate scope and provides easy efficient access to various phenanthridinones.