Chlorination of N-(N-Arylsulfonylarylimidoyl)-1,4-benzoquinone Imines and Their Reduced Forms

The study of chlorination of N-(N-arylsulfonylarylimidoyl)-1,4-benzoquinone imines and of N-(N-arylsulfonylarylimidoyl)-1,4-aminophenols revealed that the dominant stage in the process was the formation of cyclohexene structures, 4-(N-arylsulfonylarylimidoyl)imino-2,5,6-trichloro-2-cyclohexene-1- ones, resulting from addition of a Cl₂ molecule across the C = C bond of the quinoid ring. These substances suffer a prototropic rearrangements yielding N-(N-arylsulfonylarylimidoyl)-2,3,6-trichloro-4-aminophenols. The latter are the most common reaction products. The products of deeper chlorination were also obtained.