A Mild And Simple Method For The Synthesis Of Substituted Phenazines

A mild, simple, and general method has been developed for the synthesis of phenazines by cross-coupling of benzoquinones with o-phenylenediamines. Benzoquinones and o-phenylenediamines reacted smoothly to give the corresponding cross-coupled products in good to excellent yields. 1,4-Naphthoquinone also coupled with o-phenylenediamines in the presence of copper acetate at 50 degrees C to give the corresponding benzo[a]phenazines. All reactions could be carried out under air.