Manufacture of Oxyanthraquinones and Oxyanthraquinonesulphonic Acids.
Year: 1898

page_text: Date of Application, 9th Nov., 1898
Complete Specification Left, 8th July, 1899-Accepted, 12th Aug, 1899
Manufacture of Oxyanthraquinones and Oxyanthraquinonesulphonic
Acids.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
nature of this invention (which has been communicated to be from abroad by
The Farbwerke vormals Meister Lucius and Brüning, of Hoechst a/Main, in the
Empire of Germany, Chemical Manufacturers,) to be as follows:-
It is known that by heating sodium anthraquinonemonosulphonate with dilute
caustic soda-lye or caustic potash, meta-oxyanthraquinone may be obtained. From
the two anthraquinonedisulphonic acids are prepared in the same manner anthraflavic
or isoanthraflavic acid. In these cases, however, and in consequence of a simultaneous
oxidising action, alizarin or flavo-purpurin and anthrapurpurin is or are always
formed.
My foreign correspondents have now found that oxyanthraquinone and oxy-
anthraquinonesulphonic acids may be obtained free from the corresponding higher
hydroxylated anthraquinone derivatives, if solutions of alkali salts or alkaline earth
salts of anthraquinonesulphonic or anthraquinonedisulphonic acids be heated under
pressure with hydroxides of alkaline earths or similarly acting bases instead of with
caustic alkali. By these means pure meta-oxyanthraquinone is obtained free from
alizarin, if sodium anthraquinonemonosulphonate be heated under pressure for
example with hydrate of lime to from 160° to 170° C. Instead of a sodium salt, a
potassium salt or an alkaline earth salt may be employed, and hydrate of baryta and
similarly acting hydroxides may be used instead of hydrate of lime.
If anthraquinonedisulphonic acids be subjected to the same treatment, then
anthraflavic acid or isoanthraflavic acid, free from corresponding purpurin, may be
obtained. It is thus possible with a proper choice of the conditions of experiment to
eliminate only one sulphonic group and to obtain thus the hitherto unknown oxy.
anthraquinonesulphonic acids.
The following amples illustrate the umassa
EXAMPLE I.
15 kilos. of sodium anthraquinonemonosulphonate are heated, while stirring, in a
closed vessel, for 24 to 30 hours to 170° C. with 10 kilos. of lime, slaked to a paste
with 120 litres of water. The mixture of a chocolate colour being poured into about
300 litres of water, boiled and precipitated with hydrochloric acid, netaoxyanthra.
quinone separates as a light green paste.

page_text: water, boiled and precipitated with hydrochloric acid. The anthraflavic acid separates
as a light yellow paste.
EXAMPLE III.
10 kilos. of sodium a-anthraquinonedisulphonate are heated under pressure for
8 to 10 hours to 160° C. with 4 kilos. of burnt lime, slaked with 80 litres of water.
The mixture is suspended in about 80 litres of water, boiled and the calculated
quantity of sodium carbonate is added. On separation of the calcium carbonate, the
solution is acidified with hydrochloric acid, and when cold the greater part of the
a-oxyanthraquinonesulphonic acid crystallises as an acid sodium salt. The rest is
salted out with common salt. The 2-oxyanthraquinone-6-sulphonic acid forms with
soda an acid salt which crystallises well and dissolves easily in hot water with a dark
yellow colour; from the solution it crystallises on cooling in form of nodules. It is
little soluble in alcohol, insoluble in ether and benzene. The aqueous solution on
addition of sodium carbonate becomes red-brown and on addition of caustic soda-lyes
becomes dark bordeaux red. From the concentrated solution the normal salt is
precipitated by an excess of caustic soda-lye as a dark-red crystalline mass.
heating with hydrate of lime the oxyanthraquinonesulphonic acid is transformed into
anthraflavic acid. Heated with caustic soda and potassium chlorate flavopurpurin is
formed.
On
The sodium ß-anthraquinonedisulphonate yields when treated according to
Example III, 2-oxyanthraquinone-7-sulphonic acid. The sodium salt of this acid is
readily soluble in hot water with a dark yellow colour; it crystallises on cooling in
red-yellow nodules. The normal salt is dark-red. When it is heated with hydrate of
lime, isoanthraflavic acid is produced, but when it is heated with caustic soda-lye and
potassium chlorate, anthrapurpurin is produced.
Dated this 9th day of November 1898.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Manufacture of Oxyanthraquinones and Oxyanthraquinonesulphonic
Acids.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
nature of this invention (as communicated to me from abroad by The Farbwerke
vormals Meister Lucius and Brüning, of Hoechst a/Main, in the Empire of Germany,
Chemical Manufacturers,) 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 by heating sodium anthraquinonemonsulphonate with dilute
caustic soda lye or caustic potash, metaoxyanthraquinone may be obtained. From
the two anthraquinonedisulphonic acids are prepared in the same manner anthraflavic
or isoanthraflavic acid. In these cases, however, and in consequence of a simul-.
taneous oxidising action, alizarin or flavo-purpurin and anthrapurpurin is or are
always formed.
My foreign correspondents have now found that oxyanthraquinone and oxyanthra-
quinonesulphonic acids may be obtained free from the corresponding higher hydroxy-
lated anthraquinone derivatives, if solutions of alkali salts or alkaline earth salts of

page_text: anthraquinonesulphonic or anthraquinonedisulphonic acids be heated under pressure
with hydroxides of alkaline earths or similarly acting bases instead of with caustic
alkali. By these means pure meta-oxyanthraquinone is obtained free from alizarine,
if sodium anthraquinonesulphonate be heated under pressure for example with
hydrate of lime to from 160° to 170° C. Instead of a sodium salt, a potassium salt
or an alkaline earth salt may be employed, and hydrate of baryta and similarly acting
bydroxides may be used instead of hydrate of lime.
If anthraquinonedisulphonic acids be subjected to the same treatment, then anthra-
flavic acid or isoanthraflavic acid, free from corresponding purpurin, may be obtained.
It is thus possible with a proper choice of the conditions of experiment to eliminate
only one sulphonic group and to obtain thus the hitherto unknown oxyanthraquinone-
sulphonic acids.
TIL 11
EXAMPLE III.
10 kilos. of sodium a-anthraquinonedisulphonate are heated under pressure for 8 to
10 hours to 160° C., with 4 kilos. of burnt lime, slaked with 80 litres of water. The
mixture is suspended in about 80 litres of water, boiled and the calculated quantity
of sodium carbonate is added. On separation of the calcium carbonate, the solution
is acidified with hydrochloric acid, and when cold the greater part of the a-oxyanthra-
quinonesulphonic acid crystallises as an acid sodium salt. The rest is salted out
with common salt. The 2-oxyanthraquinone-6-sulphonic acid forms with soda an
acid salt which crystallises well and dissolves easily in hot water with a dark yellow
colour; from the solution it crystallises on cooling in form of nodules. It is little
soluble in alcohol, insoluble in ether and benzene. The aqueous solution on addition
of sodium carbonate becomes red brown and on addition of caustic soda-lye becomes
dark bordeaux red. From the concentrated solution the normal salt is precipitated by
an excess of caustic soda-lye as a dark red crystalline mass. On heating with hydrate
of lime the oxyanthraquinonesulphonic acid is transformed into anthraflavic acid.
Heated with caustic soda and potassium chlorate flavopurpurin is formed.
The sodium ẞ-anthraquinonedisulphonate yields when treated according to
Example III, 2-oxyanthraquinone-7-sulphonic acid. The sodium salt of this acid is
readily soluble in hot water with a dark yellow colour; it crystallises on cooling in
yellow nodules. The normal salt is dark red. When it is heated with hydrate of
lime, isoanthraflavic acid is produced, but when it is heated with caustic soda-lye and
potassium chlorate, anthrapurpurin is produced.
Having thus particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, I declare that what
I claim is-
The herein described manufacture of oxyanthraquinones and oxyanthraquinone

page_text: snlphonic acids, without a simultaneous formation of higher hydroxylated anthra-
quinone derivatives, by heating under pressure solutions of alkali salts or alkaline
earth salts of anthraquinonesulphonic acids or anthraquinonedisulphonic acids with
the hydroxides of alkaline earths or similarly acting bases.
ABEL & IMRAY,
Agents for the Applicant.