Synthesis of phenanthridinones viapalladium-catalyzed C(sp2)–H aminocarbonylation of unprotected o-arylanilines

An efficient synthesis of free (NH)-phenanthridinones through Pd-catalyzed C(sp2)–H aminocarbonylation of unprotected o-arylanilines under an atmospheric pressure of CO has been developed. Some ortho heteroarene substituted anilines as well as N-alkyl protected o-arylanilines are also suitable substrates for this C–H aminocarbonylation reaction.