Nothing to suggest the formation of an etherial salt was observed.
Analysis of this product for sulphur showed that in this galleïn, as in the case of the hydroquinone phthaleïn more than two pyrogallol residues had entered the acid residue. The indications were that six had entered into one of the chloride. This also agrees with the observation of Lyman[23], who describes a hexapyrogallol galleïn of orthosulphoparatoluic acid.
Probably a mixture of varying composition was obtained, and little importance was attached to the results save as they showed that no etherial salt is formed in the reaction.
7. The Action of β-Naphthol upon the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid.
It was hoped that here, as in the case of the monohydroxy phenols an etherial salt would be obtained. It was found, however, that very little action occurred, save such as was indicated by the development of a bright carmine color in the melted mixture, until a temperature of about 160° was reached. At this point hydrochloric acid was evolved, but the chloride itself undergoes decomposition. Nothing definite could be isolated among the reaction products, save unchanged β-Naphthol.
VIII. The Action of Aniline upon
the Symmetrical Chloride
of Paranitroorthosulphobenzoic Acid.
As has been pointed out in the Introduction, it was in connection with the aniline derivatives of orthosulphobenzoic acid, that the isomerism of the chlorides was first noticed, two anilids being obtained. Accordingly, when Gray began his study of the chlorides of paranitroorthosulphobenzoic acid, his first effort was to obtain evidence of the existence of two anilids. These were not obtained, however, until after the chlorides themselves had been isolated, as their properties made their isolation and preparation a matter of difficulty.
Some points still remained in doubt after Gray’s study, and a further investigation was thought to be desirable to clear these up.
Some time was spent in an endeavor to obtain a method by which a good yield of fusible, or symmetrical, anilid could be obtained. The yield in all cases tried, is not a good one. The presence of the nitro group appears to complicate the reaction, leading to secondary reactions whose course could not be followed. Upon bringing aniline and the chloride together, a very vivid red color was always observed, and the same was true when it was necessary to employ alkali. The fact that such colors develop when nitro compounds are treated with alkali has been noticed in many instances and some progress has been made in the study of these compounds. Jackson and Ittner[24] have lately reviewed this subject.
If a solution of the symmetrical chloride in ether is slowly added to a similar solution of aniline, no appreciable amount of heat is evolved. If the resulting solution is allowed to stand at ordinary temperatures, action proceeds very slowly, aniline hydrochloride being precipitated as the reaction proceeds. This can be filtered off from time to time and the rate of action so observed. In such a way it was found that five grams of chloride required about fifty hours time to react completely with an excess of aniline. Similar results were obtained with chloroform as the solvent. By boiling the solution for an hour or more the reaction is complete.