Unexpected quinoxalines () have been obtained from a one-pot reaction of 2-[(2-oxo-2-arylethyl)anilino]-1-aryl-1-ethanones () with o-phenylenediamine () in the presence of a catalytic amount of p-toluene sulfonic acid. The reaction presumably involves a tandem carbonyl addition—eliminative cyclization—air oxidation sequence. J. Heterocyclic Chem., 46, 332 (2009).