Pd‐Catalyzed Carbonylative Synthesis of 4 H ‐Benzo[ d ][1,3]Oxazin‐4‐Ones Using Benzene‐1,3,5‐Triyl Triformate as the CO Source

A facile synthesis of 4 H ‐benzo[ d ][1,3]oxazin‐4‐one derivatives by Pd‐catalyzed carbonylative cross‐coupling between N ‐( ortho ‐bromoaryl)amides and benzene‐1,3,5‐triyl triformate (TFBen) was developed. This procedure does not require the toxic and flammable gas CO as the carbonyl source and tolerates a wide scope of functional groups. Remarkably, 4 H ‐benzo[ d ][1,3]oxazin‐4‐ones incorporated to natural products and drugs can be constructed by this method.