Studies on the Periodic Acid Oxidation of N-Glycosides. X

Studies on the Periodic Acid Oxidation of Anilines. (3)

Abstract

Detection of 2, 5-dianilino-N, N′-diphenyl-p-benzoquinone diimine (azophenine) (V) and 2, 5-dianilino-p-benzoquinone (VI) by paper chromatography was examined and good results were obtained with (V) but it was not possible to obtain a suitable Rf value or characteristic coloration reagent for (VI). This result was utilized in detecting the presence of (V) in the periodic acid oxidation product of aniline and the presence of (VI) was assumed from its sublimability. It was also found that a minute amount of azobenzene was present.
The products from periodic acid oxidation of aniline were systematically separated and it was proved that the chief components are 2, 5-dianilino-p-benzoquinone imine (IV) in 65% yield and 2-amino-5-anilino-N-phenyl-p-benzoquinone imine (I) in 15% yield. An unknown substances (VII), m. p. 203-205° (decomp.) (in 9% yield), and (VIII), m. p. over 360° (in 6% yield), were also isolated. Content of other pigments was all very small.