Manufacture of Salicylic-acid-ester of Acetol.
Year: 1893

page_text: Date of Application, 22nd Feb., 1893
Complete Specification Left, 1st Nov., 1893—Accepted, 16th Dec., 1893
· PROVISIONAL SPECIFICATION.
Manufacture of Salicylic-acid-ester of Acetol.
I, Dr. PAUL FRITSCH, of Ludwigshafen af Rhein, Germany, Chemist, do hereby
declare the nature of this invention to be as follows:-
Many warnings have been raised, particularly by Kobert and Hesselbach, against
the employment of salol for medical purposes on the ground that phenol separated
therefrom in the human body causes carbolic acid poisoning.
Now my invention has for object to produce an ether of salicylic acid in which
the salicylic acid is combined with a non-poisonous substance.
According thereto I have produced an ether of this kind by the reaction upon
each other of monochloracetone and salicylate of soda. Upon the separation of the
resulting sodium chloride, the salicylic-acid-ester of acetol is obtained.
Of the esters of this acetol (which latter is also known as acetone-alcohol,
acetylcarbinol and pyruvyl alcohol) only acetic-acid-ester and benzon-acid-ester have
heretofore been produced. The former has becu produced by Henry (Berichte
der Deutschen chemischen Gesellschaft V, 966), and the latter has been produced by
Breuer & Zincke (Berichte der Deutschen chemischen Gesellschaft XIII, 639).
The last named chemists obtained from 80 grammes of monochloracetone only
50 grammes of benzoylacetol.
Now I have discovered that by causing a reaction between a mono-halogen acetone
such as monochloracetone, monobrom-acetone, and mon-iodo-acetone, and a salicylate
such as salicylate of soda, which reaction takes place almost quantitatively,
salicylic-acid-ester of acetol can be produced.
This reaction may be caused to take place by heating the components, with or
without solvents.
The operation can conveniently be carried out in the following manner :-
Over about 180 parts by weight of salicylate of soda, are poured about 200 parts
by weight of spirit; then about 92-5 parts by weight of monochloracetone are
added thereto, and the mixture heated on a return-flow cooler until the pungent
smell of the mono-chlorine-acetone has disappeared. The spirit is then distilled off
and the product of the reaction is poured, whilst still warm, into a dilute solution
of soda. The new ester is separated as a heavy oil that solidifies after a short
time.
The ester is purified by re-crystallization from spirit in which it is readily soluble
by the aid of heat, but in which it is only soluble with difficulty in the cold.
The reaction will also take place when the components are heated in an aqueous
or aqueous-alcoholic solution, and also-but with a less yield—when the components
are heated together without solvents.
The salicylic-acid-ester of acetol, produced according to the following
equation.:-

page_text: The salicylic acid-ester of acetol produced according to this invention is suitable
for use for medicinal purposes.
Deted this 2nd der of Wohnvann 1802
PAUL FRITSCH,
By L. W., per F. B.
COMPLETE SPECIFICATION.
Manufacture of Salicylic-acid-ester of Acetol.
I, Dr. PAUL FRITSCH of Ludwigshafen a Rhein, Germany, 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:-
Many warnings have been raised, particularly by Kobert and Hesselbach, against
the employment of salol for medical purposes on the ground that phenol separated
therefrom in the human body causes carbolic acid poisoning.
Now my invention has for object to produce an ether of salicylic acid in which
the salicylic acid is combined with a non-poisonous substance.
According thereto I have produced an ether of this kind by the reaction upon
each other of mono chloracetone and salicylate of soda. Upon the separation of the
resulting sodium chloride, the salicylic-acid-ester of acetol is obtained.
Of the esters of this acetol, which is also known as acetone-alcohol, acetyl-
carbinol, and pyruvyl-alcohol, only acetic-acid-ester and benzoic-acid-ester have
heretofore been produced. The former has been produced by Henry (Berichte
der Deutschen chemischen Gesellschaft, V, 966), and the latter has been produced
by Breuer & Zincke (Berichte der Deutschen chemischen Gesellschaft XIII, 639).
The last named chemists obtained from 80 grammes of monochloracetone only
50 grammes of benzoylacetol.
Now I have discovered that by causing a reaction between a mono-halogen
acetone such as monochloracetone, mono-brom-acetone, or mono-iodo-acetone, and a
salicylate such as salicylate of soda, which reaction takes place almost quantitatively,
salicylic-acid-ester of acetol can be produced.
This reaction may be caused to take place by heating the components, with or
without solvents.
The operation can conveniently be carried out in the following manner :-Over
about 180 parts by weight of salicylate of soda, are poured about 200 parts by
weight of spirit (common alcohol); then about 92.5 parts by weight of mono-chlor-
acetone are added thereto, and the mixture heated on a return-flow cooler until the
pungent smell of the mono-chlor-acetone has disappeared. The spirit is then
distilled off and the product of the reaction is poured, whilst still warm, into a
dilute solution of soda. The new ester is separated as a heavy oil that solidifies
after a short time.
The ester is purified by re-crystallization from spirit in which it is readily soluble
by the aid of heat, but in which it is only soluble with difficulty in the cold.
The reaction will also take place when the components are heated in an aqueous
or aqueous-alcoholic solution, and also-but with a less yield-when the components
are heated together without solvents.
The salicylic-acid-éster of acetol, produced according to the following
equation:-
COON.
COOCH COCH

page_text: "
warm alcohol, in ether, bi-sulphide of carbon, chloroform and benzol; and soluble
only with difficulty in cold alcohol and in ligroin.
By letting it stand for a short time with ammonia or dilute solution of soda it is
saponified with great facility.
The salicylic-acid-ester of acetol produced according to this invention is suitable
for use in medicinal purposes.
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 of salicylic-acid-ester of acetol, by heating a salicylate with a
mono-halogen-acetone, with or without solvents, as set forth.
Dated this 1st day of November 1893.
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.