6N-containing polyphenylene precursors were generated via [2 + 2 + 2] cyclotrimerisation. On methoxy substitution complete ring-closure can be achieved (via FeCl₃-mediated oxidative cyclodehydrogenation) to give asymmetric and C_3v symmetric hexaazasuperbenzenes. Investigations using DDQ/H⁺ mediated conditions reveal this to be a promising alternative and selective route to partial cyclodehydrogenation.