Manufacture of Para-xy-para-amidodiphenylamine,
Year: 1899

page_text: Date of Application, 25th Oct., 1899
PROVISIONAL SPECIFICATION.
Manufacture of Para-xy-para-amidodiphenylamine,
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, in
the County of London, Chartered Patent Agent, do hereby declare the nature
of this invention (as communicated to me from abroad by The Farbwerke
vormals: Meister Lucius & Brüning, of Hoechst */Main, in the Empire of
Germany, Chemical Manufacturers) to be as follows:-
Para-oxy-para-amidodiphenylamine may be obtained by heating para-pheny-
lenediamine with a para-amidophenolate (French Patent No. 289214).
My foreign correspondents have found a new and more convenient method of
producing this substance by heating the easily obtained para-oxy-para-amido-
diphenylamine-ortho-sulphonic acid in a slightly acidified solution under pres-
sure to about 150° C., when a sulphonic group is eliminated and a good yield
of the substance in question is obtained.
EXAMPLE:
200 kilos. of para-oxy-para-amidodiphenylamine-ortho-sulphonic acid, 50 kilos.
of sulphuric acid of 60° Bé. specific gravity and 1500 litres of water are heated
with active stirring in a closed vessel for 6 hours to 150° C. A brown-coloured
solution is obtained which is filtered hot to remove small impurities; it is
then allowed to cool in suitable vessels when the new substance separates as a
sulphate in the form of grey-white crystals. If the solution is treated with
sodium carbonate the base separates as a white precipitate, which at first is
dirty, but soon becomes dark by oxidation when exposed to the air.
The free base forms, when dry, a more or less dark coloured powder easily
soluble in alcohol and ether; on evaporating an ethereal solution thereof, there
remain small white laminæ having the melting point 157° to 159° C.
Dated this 05th day of October 1000
ABEL & IMRAY,
Agents for the Applicant.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, in
the County of London, Chartered Patent Agent, do hereby declare the nature
of this invention (as communicated to me from abroad by The Farbwerke
vormals: Meister Lucius & Brüning, of Hoechst */Main, in the Empire of
Germany, Chemical Manufacturers) and in what manner the same is to be per-
CD
017

page_text: formed, to be particularly described and ascertained in and by the following
statement:
-
Para-oxy-para-amidodiphenylamine may be obtained by heating para-pheny-
lenediamine with a para-amidophenolate (French Patent No. 289244).
My foreign correspondents have found a new and more convenient method of
producing this substance by heating the easily obtained para-oxy-para-amido-
diphenylamine-ortho-sulphonic acid in a slightly acidified solution under pres-
sure to about 150° C., when a sulphonic group is eliminated and a good yield
of the substance in question is obtained.
EXAMPLE:
200 kilos. of para-oxy-para-amidodiphenylamine-ortho-sulphonic acid, 50 kilos.
of sulphuric acid of 600 Bé. specific gravity and 1500 litres of water are heated
with active stirring in a closed vessel for 6 hours to 150° C: A brown-coloured
solution is obtained which is filtered hot to remove small impurities; it is
then allowed to cool in suitable vessels when the new substance separates as a
sulphate in the form of grey-white crystals. If the solution is treated with
sodium carbonate the base separates as a white precipitate, which at first is
dirty but soon becomes dark by oxidation when exposed to the air.
The free base forms, when dry, a more or less dark coloured powder easily
soluble in alcohol and ether; on evaporating an ethereal solution thereof, there
remain small white laminae having the melting point 157° to 159° C.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
The herein described manufacture of para-oxy-para-amidodiphenylamine by
heating in a closed vessel para-oxy-para-amidodiphenylamine-ortho-sulphonic
acid in feebly acid solution to a temperature above 100° C.
Dated this 25th day of June 1900.
ABEL & IMRAY,
Agents for the Applicant.