Improvements in the Manufacture or Preparation of Alkyl Derivatives of Hydroxy-methyleneuric Acids.
Year: 1899

page_text: Date of Application, 14th Feb., 1899-Accepted, 22nd Apr., 1899
Improvements in the Manufacture or Preparation of Alkyl
Derivatives of Hydroxy-methyleneuric Acids.
I, GEORGE WILLIAM JOHNSON, of 47, Lincoln's Inn Fields, in the County of London
Patent Agent, do hereby declare the nature of this invention (which has been
communicated to me from abroad by C. F. Boehringer & Soehne of Waldhof, near
Mannheim, in the German Empire) and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement :-
As already mentioned in the Specification of the application for Letters Patent
No. 20447 dated the 27th September 1898 the hydroxy-methylene-derivatives of uric
acid and its alkylic derivatives lose formaldehyde when heated with water, acids, or
alkalis, regenerating the corresponding uric acid.
My foreign correspondents have found that it is nevertheless possible to alkylate the
compounds mentioned, in alkaline solution, by employing, with additions, the methods
described in the Specifications of Letters Patent No. 10005 dated the 11th May
1896 and No. 2472 dated the 29th January 1897.
The hydroxymethylene group is not eliminated during the process of alkylation; the
methylation of 7-hydroxymethyleneuric acid, for instance, proceeds in accordance
with the following equation.

page_text: possible to prepare conveniently those alkyluric acids which have not yet been
obtained by alkylation of uric acid, as, for example, 1: 3- dimethyluric acid.
Not only may the hydroxymethyleneuric acids characterised in the Specification
of the aforesaid application for Letters Patent No. 2044708 be submitted to further
alkylation, but also the compound of uric acid containing more than one molecular
proportion of formaldehyde which has been described in the meantime by Tollens
(Berichte d. deutschen chem. Gessel. 30. 2514); the latter on alkylation loses a
portion of the formaldehyde, yielding 3-methyl-7-hydroxy-methyleneuric acid.
The following examples serve to explain the Invention more fully. The parts are
by volume.
I. PREPARATION OF 3-METHYL-7-HYDROXYMETHYLENEURIC ACID.
15 parts of 7-hydroxymethyleneuric acid are dissolved in 50 parts of double
normal potash (1 molecular proportions) and 50 parts of water with gentle heat;
13 parts of methylic iodide are added to the cooled solution, and the liquid heated
at 80-85° Centigrade and agitated in autoclaves for two hours.
On cooling, crystals separate, which are almost colourless and consist for the most
part of 3-methyluric acid. This is removed by filtration, 3-methyl-7-hydroxymethy-
leneuric acid crystallising from the filtrate after standing for a considerable time
or by evaporation in vacuum.
Its properties have been already described in the specification of the aforesaid
application for Letters Patent No. 2044798.
In the preparation of 3-methyl-7-hydroxymethyleneuric acid, it is unnecessary.to
Start with pure hydroxymethyleneuric acid. Potassium urate can be also used, one
part thereof being heated at 90° Centigrade with. 5.5 parts of a 40 per cent. solution
of formaldehyde, 7.5 parts of methylic iodide and 7-8 parts of water for two hours, the
beating being effected in autoclaves and accompanied by agitation.
The solution obtained in this way is further treated as herein before described, or
applied to the preparation of 3-methyluric acid or 3: 7-dimethyluric acid.
II. PREPARATION OF 1: 3-DIMETHYL-7-HYDROXYMETYHLENEURIC ACID.
5 parts of 3-methyl-7-hydroxymethyleneuric acid are,dissolved in 25 parts of double
normal potash and 25 parts of water and agitated with 4.5 parts of methylic iodide
until the latter disappears. The alkylation is complete at the end. of 48 hours, an
alkaline solution of 1: 3-dimethyl-7-hydroxymethyleneuric acid being produced
from which 1 3-dimethyl-7-hydroxymethyleneuric acid can be obtained by rendering
the solution slightly acid, and evaporating. By elimination of formaldehyde it yields
13 dimethyluric acid.
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 manufacture, or preparation, of alkylated hydroxymethylene-uric acids by
treating an alkaline solution, of a hydroxymethylene-níric acid with a haloid ether,
substantially as hereinbefore'described."!
JOHNSONS & WILLCOX,
.47 Lincoln's Inn Fields, London, W.C., Agents,