Diamination of Phenylene Dihalides Catalyzed by a Dicopper Complex

Diamination of phenylene dihalides with aqueous ammonia to give the corresponding phenylenediamines can be achieved by using a dicopper complex [Cu-2(bpnp)(OH)(CF3COO)(3)] (1) (bpnp = 2,7-bis(pyridine-2-yl)-1,8-naphthyridine) as the catalyst in the presence of Bu4NBr and Cs2CO3 in high yields. In addition, 1,3,5-tribromobenzene was converted into benzenetriamine quantitatively under the same conditions. This method offers a new opportunity, particularly simplifying steps and increasing yields, for the preparation of aryl diamines.