Practical chemoselective aromatic substitution: the synthesis of <i>N</i>-(4-halo-2-nitrophenyl)benzenesulfonamide through the efficient nitration and halogenation of <i>N</i>-phenylbenzenesulfonamide
the metal-promoted tandem nitration and halogenation of N-phenylbenzenesulfonamide to synthesize N-(4-halo-2-nitrophenyl)benzenesulfonamide derivatives has been developed. The method shows highly practical chemoselective and functional group compatibility. In addition, it employs insensitive and inexpensive Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, and NH4NO3 as the nitrationreagents, and it provides a direct