The Production from Carbazol of a New Derivative to be used in the Manufacture of Colouring Matters.
Year: 1888

page_text: Date of Application, 9th Oct., 1888
Complete Specification Left, 9th July, 1889-Accepted, 10th Aug., 1889
PROVISIONAL SPECIFICATION.
The Production from Carbazol of a New Derivative to be used in
the Manufacture of Colouring Matters.
I, JAMES YATE JOHNSON, of 47 Lincolns Inn Fields, in the County of Middlesex,
Gentleman, do hereby declare the nature of this invention which has been communi-
cated to me from abroad by the Badische Anilin and Soda Fabrik of Ludwigshafen-
on-the-Rhine in the Empire of Germany, to be as follows
This Invention relates to the production from carbazol of a new derivative tormed
diamido-carbazol for use in the manufacture of colouring matters.
In carrying out this Invention carbazol is first converted into dinitrocarbazol by
allowing for instance about thirteen parts by weight of nitric acid of about 1.38
specific gravity gradually to run into a well agitated mixture of about ten parts by
weight of carbazol with about fifty parts by weight of glacial acetic acid at a tempera-
ture of about 80° Centigrade. After the addition of nitric acid the temperature of
the mixture is raised to about 100° Centigrade and maintained thereat for about half
an hour. The result of the operation is then allowed to cool when dinitrocarbazol will
separate out which is then filtered and washed. It is then submitted to the action of
reducing agents in order to convert it into its corresponding diamido derivative. For
this purpose a reducing process may be employed such as for instance treatment
with stannous chloride or with a mixture of tin and hydrochloric acid at about
100° Centigrade but by preference the action of zinc dust in the presence of caustic
alkalies is made use of in the following manner.
About 65 parts by weight of dinitrocarbazol are intimately mixed with about three
hundred parts by weight of water and about one hundred parts by weight of zince
dust and the mixture is heated to about 50° Centigrade and about two hundred
and fifty parts by weight of caustic soda liquor of about 1.38 specific gravity
After the addition of caustic soda
gradually added to the well agitated mixture.
the temperature is raised to about 90° Centigrade and is maintained thereat for
about eight hours or until the conversion of dinitrocarbazol into diamidocarbazol
has been completed or nearly so. In order to separate the said diamido compound
from the alkaline mixture about one thousand parts of water are then added the
undissolved residue (principally consisting of diamidocarbazol and unchanged zinc
dust) is filtered washed and treated with about five hundred parts by weight of
hydrochloric acid of about 1.16 specific gravity whereby a crystalline mixture of
hydrochlorate of diamidocarbazol and of its chloride of zinc compound will be
obtained which is then filtered and pressed. A further purification may afterwards be
effected by dissolving the said saline compounds of diamidocarbazol in about 15 hundred
parts by weight of water and precipitating the filtered solution (which may be
previously decolorized by means of animal charcoal) by the addition of about one
hundred parts of crystallized sulphate of soda when sulphate of diamidocarbazol thus
produced will separate out in a pure and well crystallized condition. The said saline.
compound is almost insoluble in pure water but dissolves readily in water acidulated
in a mineral acid.
From its aqueous solution pure diamidocarbazol may be obtained upon the addition
of an alkali as a crystalline precipitate consisting of silverish white lamina hardly
soluble in water and not entering into fusion at about 250° Centigrade.
The diamidocarbazol may be treated in any suitable manner for the production
of tetrazo-carbazol for example as described in my application of even date
herewith.
1000

page_text: COMPLETE
SPECIFICATION.
The Production from Carbazol of a New Derivative to be Used in
the Manufacture of Colouring Matters.
I JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention (which has been communi-
cated to me from abroad by the Badische Anilin and Soda Fabrik of Ludwigshafen-
on-the-Rhine 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 :-
--
This Invention relates to the production from Carbazol of a new derivative termed
diamidocarbazol for use in the manufacture of colouring matters.
In carrying out this Invention carbazol is first converted into dinitro carbazol by
allowing, for instance, about thirteen parts by weight of nitric acid of about 1.38
specific gravity gradually to run into a well agitated mixture of about ten parts by
weight of carbazol with about fifty parts by weight of glacial acetic acid at a
temperature of about eighty degrees centigrade. After the addition of nitric acid
the temperature of the mixture is raised to about one hundred degrees centigrade
and maintained thereat for about half an hour. The result of the operation is then
allowed to cool, when dinitro carbazol will separate out in the form of a yellow
crystalline powder which is then filtered and washed.
Dinitro carbazol thus obtained is then submitted to the action of reducing agents
in order to convert the same into its corresponding diamido derivative. For this
purpose any suitable reducing process may be employed, such as for instance treat-
ment with stannous chloride or with a mixture of tin and hydrochloric acid at about
one hundred degrees centigrade, but by preference the action of zinc dust in the
presence of caustic alkalies is made use of in the following manner.
About sixty five parts by weight of dinitro-carbazol are intimately mixed with about
three hundred parts by weight of water and about one hundred parts by weight of
zine dust. The mixture thus prepared is then heated to about fifty degrees centi-
grade and about two hundred and fifty parts by weight of caustic soda liquor of about
138 specific gravity are gradually added to the well agitated mixture. After the
addition of caustic soda the temperature is raised to about ninety degrees centigrade
and maintained thereat for about eight hours or until the conversion of dinitro
carbazol into diamido carbazol has been completed or nearly so. In order to separate
the said diamido compound from the alkaline mixture, about one thousand parts by
weight of water are then added, the undissolved residue (principally consisting of
diamido carbazol and unchanged zinc dust or oxide of zinc) is filtered, washed and
treated with about five hundred parts by weight of hydrochloric acid of about 1·16
specific gravity, whereby a crystalline niixture of hydrochlorate of diamido carbazol
and of its chloride of zinc compound is obtained, which is then filtered and pressed.
A further purification may afterwards be effected by dissolving the said saline
compounds of diamido carbazol in about fifteen hundred parts by weight of water
and precipitating the filtered solution (which may be previously decolorized by
means of animal charcoal) by the addition of about one hundred parts of crystal-
lized sulphate of soda, when sulphate of diamido carbazol thus produced will
separate out in a pure and well crystallised condition. The said saline compound is
almost insoluble in pure water, but dissolves readily in water acidulated by a mineral
acid. From its aqueous solution pure diamido carbazol may be obtained upon the
addition of an alkali as a crystalline precipitate consisting of silverish white
lamina, hardly soluble in water and not entering into fusion at about 250 degrees
centigrade.
The diamido carbazol may be used in the manufacture of colouring matters in any
suitable manner such for instance as that described in the Specification of my appli-
cation for Letters Patent No. 14478 of even date with this.

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 of the herein before described diamido carbazol produced
by converting Carbazol first into dinitro carbazol by the action of nitric acid and
then treating the said dinitro compound with reducing agents, substantially as herein-
before described.
J. H. JOHNSON & Co.,
Agents.