The Manufacture and Production of Benzo-sulphonimides, or their Nitro or Halogen Substitution Derivatives.
Year: 1895

page_text: Date of Application, 1st May, 1895-Accepted, 22nd June, 1895
ATICATION.
The Manufacture and Production of Benzo-sulphonimides, or their
Nitro or Halogen Substitution Derivatives.
I, GEORGE WILLIAM JOHNSON of 47 Lincoln's Inn Fields in the County of
Middlesex Patent Agent, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Dr. F. von Heyden, Nachfolger of
Radebeul near Dresden in the Empire of Germany) and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement :-
It is known that benzo-sulphonimide results from the oxidation of toluene-
sulphonaniide with permanganate of potash. It is also known that permanganate of
potash can be produced by electrolytical oxidation of manganate of potash. Thus
the permanganate of potash acts as a transferrer of the electrolytical oxygen.
This invention consists in the omission of the said oxygen transferrer and in
the direct oxidation of the toluene-sulphonamide by means of the electric current.
The production of benzo-sulphonimides by electrolytical oxidation of toluene-
sulphonamide according to this invention may be effected in the following way.
Toluene-sulphonamide is dissolved in water with caustic alkali or an alkaline
earth for example with caustic soda, caustic potash, quicklime or barium hydroxide.
This solution may be produced by dissolving 2 kilogrammes of caustic soda in
from 50 to 100 litres of either cold or hot water and by adding 10 kilogrammes of
toluene sulphonamide and stirring the mixture well. Or instead of the
2 kilogrammes of caustic soda 1 to 3 kilogrammes of quicklime may be employed.
Through the solution of salts of toluene-sulphonamide thus obtained a current of
electricity is passed. The said current should be so regulated as to allow little or
no oxygen to escape at the oxygen electrode so that as full advantage as possible is
taken of the oxygen in the oxidation of the toluene sulphonamide. The character
of the electric current employed will depend in some measure upon the arrange-
ment and construction of the electrolytic apparatus and therefore the current will
be decided by exp. rimeat in the part ular apparatus employed in the process. At
intervals small quantities of alkali or alkaline earth are added to the solution of the
amide salt in order to prevent the precipitation of free amide being caused by the
carbonic acid which is either absorbed from the atmosphere or produced as a bye
product in the course of the electrolytical process.
After the termination of the electrolytical process the solution is treated with
hydrochloric acid, the resulting precipitate, consisting of benzosulphoninide and
toluene sulphonamide, is filtered and neutralized with a solution of soda. The
toluenesulphonamide remains undissolved, the benzosulphonimide is dissolved and
may be precipitated from the filtered solution by the addition of hydrochloric
acid.
If the electrolized toluenesulphonamide contain para-amide besides ortho-amide
the resulting benzosulphonimide will contain parasulphaminebenzoic acid.
If instead of toluenesulphonamide the nitro or halogen substitution derivatives of
this product be oxydized by electrolysis as described the nitro or halogen
substitution derivatives of benzosulphonimide are produced.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The manufacture and production of benzosulphonimides or their nitro or halogen
substitution derivatives by the oxydation of toluenesulphonamide or of its nitro or
halogen substitution derivatives by electrolysis as hereinbefore explained.
Dated this 1st day of May 1895.
JOHNSONS & WILLCOX,
Agents.