Process for the Production of Mono-bromo- and Di-bromo-para-oxy- Benzoic Acid suitable for Conversion into Proto-catechuic Acid, Pyro-catechin, and the like.
Year: 1891

page_text: Date of Application, 23rd Mar., 1891
Complete Specification Left, 8th Dec., 1891-Accepted, 9th Jan., 1892
PROVISIONAL SPECIFICATION.
Process for the Production of Mono-bromo- and Di-bromo-para-oxy-
Benzoic Acid suitable for Conversion into Proto-catechuic Acid,
Pyro-catechin, and the like.
I JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman 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) to be as follows:-
In chemical literature (Beilstein's Organische Chemie, 2nd Edition Vol. II.
p. 983) statements have appeared, based on the experiments made by Hasiwetz and
Barth (Liebig's Annalen 134; 276) to the effect that the action of bromine on
para-oxy-benzoic acids does not form a substitution product thereof but that with
splitting off of carbon dioxide tribromo phenol is produced.
For the production of brominised or brominated para-oxy-benzoic acids, anisic
acid has heretofore been solely employed (Laurent, Cahours, Salkowski).
According to the process hereinafter described brominized para-oxy-benzoic acids
are very readily obtained by the direct action of bromine upon para-oxy-benzoic
acid and the alkyl esters thereof. This can be effected as follows:-
I. part of para-oxy-benzoic acid or para-oxy-benzoic-acid-alkyl-ester is stirred
with glacial acetic acid and gradually mixed with the quantity of bromine corre-
sponding to one molecule. After standing for some time with occasional stirring
the mono-bromo-para-oxy-benzoic acid or its ester can be separated by diluting
with water.
II. Para-oxy-benzoic acid alkyl-ester is dissolved in the corresponding quantity
of soda lye gradually decomposed with two molecular proportions of bromine and
the separated alkyl ester of the dibromo-para-oxy-benzoic acid filtered off.
Para-oxy-benzoic acid when similarly treated produces tri-bromo-phenol. The
bromo-para-oxy-benzoic acids can be readily converted in the known manner into
proto catechuic acid and gallic acid or pyro catechin.
1
1801
J. H. JOHNSON & CO.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
Process for the Production of Mono-bromo- and Di-bromo-para-oxy-
Benzoic Acid suitable for Conversion into Proto-catechuic Acid,
Pyro-catechin, and the like.
I, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields, in the County of Middlesex
Gentleman, 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 :-
In chemical literature (Beilstein's Organische Chemie 2nd Edition Vol. II.
page 983) statements have appeared based on the experiments made by Hlasiwetz
and Barth (Liebig's Annalen 134; 276) to the effect that the action of bromine on
para-oxy-benzoic acids does not form a substitution product thereof but that, with
splitting off of carbon dioxide, tribromo-phenol is produced.

page_text: For the production of brominised, or brominated, para-oxy-benzoic acids, anisic
acid has heretofore been solely employed (Laurent, Cahours, Salkowski).
According to the process hereinafter described brominised para-oxy-benzoic acids
are very readily obtained by the direct action of bromine upon para-oxy-benzoic
acid and the alkyl esters thereof. This can be effected as follows:-
I. 1 part of para-oxy-benzoic acid or para-oxy-benzoic-acid-alkyl-ester is stirred
with glacial acetic acid and gradually mixed with one molecular proportion of
bromine. After standing for some time with occasional stirring the mono-bromo-
para-oxy-benzoic acid or its ester can be separated by diluting with water.
II.
Para-oxy-benzoic-acid-alkyl-ester is dissolved in the corresponding quantity
of soda lye two molecular proportions of bromine are gradually added and the
separated alkyl-ester of the dibromo-para-oxy-benzoic acid filtered off. Para-oxy-
benzoic acid when similarly treated produces only the known tri-bromo-phenol.
The bromo-para-oxy-benzoic acids can be readily converted in the known manner
into proto catechuic acid and gallic acid or pyro catechin.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is
The process for the production of mono-bromo-para-oxy benzoic acid by the
action of bromine upon para-oxy-benzoic acid or the esters thereof suspended or
dissolved in glacial acetic acid, and of dibromo-para-oxy-benzoic acid by brominising
or brominating the para-oxy benzoic acid ester in an alkaline solution.
Dated thin 7th day of December 1801
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.