Palladium/Silver Synergistic Catalysis in Direct Aerobic Carbonylation of C(sp(2))-H Bonds Using DMF as a Carbon Source: Synthesis of Pyrido-Fused Quinazolinones and Phenanthridinones.

An unprecedented Pd/Ag synergistic catalysis in the direct carbonylation of C(sp(2))-H bonds utilizing DMF as the carbon source under oxygen is described and demonstrated in the synthesis of pyrido-fused quinazolinone and phenanthridinone scaffolds. Control experiments indicated that the "C" of the carbonyl group is derived from the methyl group of DMF and "O" originates from oxygen as in the case of Ge's recent work. This transformation offers an alternative avenue for "CO-free" carbonylations.