A highly practical and convenient halogenation of fused heterocyclic N-oxides

A novel, mild and practical method for the regioselective halogenation of fused azine N-oxides and diazine N-oxides has been developed. The procedure is operationally simple, compatible with a broad range of functional groups, and all of the reagents associated are cheap and easy to obtain. The potential extension of this method to a one-pot oxidation/bromination sequence that obviates the need for isolation of the N-oxide intermediates is also presented.