Interrupted Fischer-Indole Intermediates via Oxyarylation of Alkenyl Boronic Acids

The oxyarylation of alkenyl boronic acids with N-arylbenzhydroxamic acids has been achieved under both copper-mediated and copper-catalyzed conditions to provide access to interrupted Fischer-indole intermediates. This transformation is believed to proceed through a copper-promoted C–O bond forming event followed by a [3,3] rearrangement. The scope of the method is described and mechanistic experiments are discussed.