Copper-mediated multiple C-H functionalization of aromatic N-heterocycles: Bromoamination of indoles and pyrroles

A copper-mediated bromoamination of aromatic N-heterocycles has been achieved using oxime esters as the N-reagents under mild conditions (ca. 70 °C). The reaction with N-alkyl indoles proceeds regioselectively to produce the 2-amino-3-bromo indole derivatives as confirmed by X-ray crystallographic analysis of the bromoaminated product, 3aa-Br. With N-methylpyrrole both the monobromoaminated and dibromoaminated products were produced by this method.