Carbonylative Synthesis of Fused Quinoxalinones via Palladium-Catalyzed Cascade Cyclization of 2-Heteroaryl Iodobenzene and NaN 3 .

A facile and straightforward approach for the synthesis of fused quinoxalinones via palladium-catalyzed cascade carbonylative cyclization of 2-heteroaryl iodobenzene and NaN 3 has been achieved. The transformation might undergo cascade carbonylation, formation of acyl azide, a Curtius rearrangement, and an intramolecular cyclization sequence. The obtained heterocycle products can be easily transformed into other structurally diverse valuable compounds, which demonstrates the synthetic utility of the developed protocol.