Palladium-Catalyzed Carbonylation for General Synthesis of Aurones Using CO 2

The carbonylation of alkynes using CO to generate aurones is to date unknown. In this study, a palladium-catalyzed carbonylation of terminal aromatic alkynes and the waste hydrosilane, poly(methylhydrosiloxane) (PMHS), is carried out with 2-iodophenol using CO to produce aurones. A variety of terminal alkynes and substituted 2-iodophenols are transformed into aurones in good yields. Preliminary mechanistic studies indicate that silyl formate, generated from CO and PMHS, plays a crucial role in the carbonylation reaction.