Synthesis and Characterization of Tetraarylphenazine and Tetraaryldibenzo[b,i]phenazine.

Phenazine and 6,13-diazapentacene are nitrogen-containing linear heterocycles that have attracted significant attention in the fields of organic electronics, and materials science. A straightforward strategy has been developed to construct 1,4,6,9-tetraarylphenazines and 5,7,12,14-tetraaryl-6,13-diazapentacenes with 1,4,6,9-tetrabromophenazine and 5,6,12,14-tetrabromo-6,13-dihydrodibenzo[b,i]phenazine as the key intermdiates, which were obtained easily from the bromination of phenazine and 6,13-dihydrodibenzo[b,i]phenazine, respectively. While the Pd-132 catalyzed ligand-free Suzuki couplings between above ascribed intermediates and various arylboronic acids were performed to afford directly tetraarylphenazines or tetraaryl-6,13-diazapentacenes by sequent oxidations. All of the new compounds are fully characterized by spectroscopy.