Palladium-catalyzed anilide ortho-arylation and subsequent one-pot cyclization to phenanthridines.

The palladium-catalyzed direct arylation of anilides possessing several N-acyl substituents has been demonstrated. Removal of the acyl group by base hydrolysis allows a short and efficient synthesis of 2-aryl or 2,6-diarylanilines. The method is functional group tolerant and allows the presence of chloride and bromide substituents on both the anilide and aryl iodide coupling components. The arylation products can be converted to phenanthridines by the reaction with trifluoroacetic anhydride.