We disclose herein electro-oxidative synthesis as the
general protocol
for procuring phenazines under mild reaction conditions. Using aerial
oxygen as an oxidant, inexpensive electrolyte, and electrodes, a diverse
range of phenazines have been accessed in good yields via the ring
contraction of 10,11-dihydro-5H-dibenzo[b,e][1,4]diazepines. In addition, the syntheses of phenazines and diamino
phenazines via direct electro-oxidation of dihydrophenazines and electro-dimerization
of o-phenylenediamines, respectively, have also been
accomplished.