A Process for the Production of Aromatic Dithio-oxycarbon Acids.
Year: 1888

page_text: Date of Application, 8th Oct., 1888
Complete Specification Leit, 4th July, 1889-Accepted, 8th Oct.,
1889
PROVISIONAL SPECIFICATION.
A Process for the Production of Aromatic Dithio-oxycarbon Acids.
I, HEINRICH BAUM, of Frankfort on Main, Chemist, do hereby declare the nature
of this invention to be as follows:
--
I have observed that the oxycarbon acids of the aromatic series and likewise those
of naphthaline, combine with sulphur chloride or sulphur bromide to form dithio-
oxycarbon acids and hydrochloric or hydrobromic acid.
A series of interesting, and more or less important, dithio-acids may be manufactured
in this manner, their formation being thus represented :-
wherein R represents an aromatic radical.
The operation is effected by simply heating corresponding molecules of the oxycarbon
acids and sulphur chloride or bromide to from 120° to 150° C. until the evolution of
hydrochloric or hydrobromic acid ceases.
To produce Dithio-salicylic acid for example 138 kilos of salicylic acid are heated
with 68 kilos of sulphur chloride (S C) to from 100° to 150° C. until the evolution of.
hydrochloric acid ceases. On the termination of the reaction, the honey-yellow-mass
is entirely dissolved in soda without leaving any residue of sulphur. If the reaction
be quite complete, the dark-yellow solution will contain no more salicylic acid, but
a new acid containing sulphur will be precipitated from the solution by means of
hydrochloric acid, as a resin-like straw-yellow mass. The acid is readily soluble in
benzole and glacial acetic acid, forming when dried and cooled a straw-yellow brittle
mass easily meltable like resin.
The sodium salt of the acid precipitates from the concentrated aqueous solution
in a light egg-yellow crystalline form and when dried forms a greenish yellow
in-coherent mass which can be easily rubbed to a yellow powder.
The production of the homologous and isomeric acids, and likewise of the a and B
dithio-naphthol-carbon acids is effected in a similar manner to that of dithio-salicylic
acid.
Dated this 8th day of October 1883
COMPLETE SPECIFICATION.
A Process for the Production of Aromatic Dithio-oxycarbon Acids.
I, HEINRICH BAUM of Frankfort on Main, Chemist do hereby declare the nature
of this invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
I have observed that the oxycarbon acids of the aromatic series, and likewise those
of naphthaline, combine with sulphur chloride or sulphur bromide to form dithio-
oxycarbon acids and hydrochloric or hydrobromic acid.

page_text: A series of interesting, and more or less important, dithio-acids, may he
manufactured in this manner, their foruiation being thus represented:-
wherein R represents an aromatic radical.
The operation is effected by simply heating equal molecules of the oxycarbon acids
and sulphur chloride or bromide to from 120° to. 150° C. until the evolution of
hydro-chloric or hydrobromic acid ceases.
To produce dithio-salicylic acid, for example, 138 kilos of salicylic acid are heated
with 68 kilos of sulphur chloride (S, Cl) to from 100° to 150° (until the evolution
of hydrochloric acid ceases.
In order to prepare the soluble salts of the dithio-salicylic acid, as for instance
the soda salt, the acid is treated with the corresponding base, as for instance soda,
wherein the honey-yellow mass is entirely dissolved without leaving any essential
residue of sulphur.
If the reaction be quite complete, the dark yellow solution will contain no more
salicylic acid but a new acid containing sulphur will be precipitated from the solution
by means of hydrochloric acid as a resin-like straw-yellow mass. The acid is readily
soluble in benzole and glacial acetic acid, forming when dried and cooled a straw-
yellow brittle mass easily meltable like resin.
The sodium salt of the acid precipitates from the concentrated aqueous solution in
a light egg-yellow crystalline form, and when dried forms a greenish-yellow.
incoherent mass which can be easily rubbed to a yellow powder.
Having now particularly described and ascertained the nature of my said inven-
tion, and the manner in which the same is to be carried out in practice, I wish it
to be understood that I do not limit myself to the exact data as regards temperature
or proportions, mentioned by me as they may vary within certain limits without
departing from my invention, but I declare that what I claim is :-
The herein described process, which consists essentially in the reaction of sulphur
chloride or sulphur bromide upon aromatic oxycarbon acids or upon the salts of said
acids at suitable temperatures, as specified.
Dated this 4th day of July 1889.
H. BAUM.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.