On boiling the dianil with alcoholic potash for a time, the solution
turned red, and nothing but tarry products were obtained. In this
respect the dianil differs from the dianil of orthosulphobenzoic acid,
which under similar conditions, is transformed into infusible anilid.
This observation is, however, in keeping with the fact that the nitro
derivative, is in general much less stable in the presence of alkali.