Palladium‐Catalyzed Oxidative Carbonylation of the Alkenyl CH Bonds of Enamides: Synthesis of 1,3‐Oxazin‐6‐ones

Palladium and CO.: The title reaction proceeds in the presence of CO, thus providing a synthesis for 1,3-oxazin-6-ones (see scheme; DABCO=1,4-diazabicyclo[2.2.2]octane, DMF=N,N-dimethylformamide). The reaction tolerates a variety of functional groups on both the aryl ring and the amide of the substrate. Initial mechanistic studies suggest the activation of the alkenyl CH bond to be a key step.