The Manufacture and Production of New Nitrosamine Compounds suited for Use in the Preparation of Diazo-compounds.
Year: 1894

page_text: Date of Application, 16th Feb., 1894
Complete Specification Left, 2nd Nov., 1894-Accepted, 8th Dec., 1894
PROVISIONAL SPECIFICATION.
The Manufacture and Production of New Nitrosamine Compounds
suited for Use in the Preparation of Diazo-compounds.
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 The Badische Anilin & Soda Fabrik of
Ludwigshafen-on-Rhine in the Empire of Germany) to be as follows:-
This invention relates to a further development of the invention the nature of
which is described in the Provisional Specification of my application for Letters
Patent No. 20605 of 1893.
In the said Provisional Specification the conversion of certain diazo-compounds
into new nitrosamines and the useful application of these bodies are described.
The diazo-compounds which are stated to be capable of use are principally those
derived from such amines as contain a substituting acid group or substituting acid
groups, such for instance, as nitro-groups, halogens sulpho groups and the like.
The present invention relates to modifications in the processes described in the
aforesaid Provisional Specification with the object of applying the said processes to
a large number of diazo-compounds not specifically indicated in the foregoing para-
graph and to obtain from these diazo-compounds also, new nitrosamines capable of
useful industrial application in the production of azo-dyes on, or in, the presence of
the goods to be dyed. In this way the number of shades of colour obtainable by
the use of the new nitrosamine compounds is largely increased and in respect to
other qualities also the dyer is afforded a wider range of choice.
The principal variation in this process is in point of temperature. Thus on
treating some diazo compounds with a caustic alkali or the like at the ordinary
temperature no conversion into the corresponding nitrosamine can be effected, but
my foreign correspondents have found that by effecting the treatment at a suitable
elevated temperature which varies in different cases, the new nitrosamines can
readily be obtained.
Another point of difference in the reaction in such cases is the production of the
alkali-salt of the diazo-compound as an intermediate product before the formation
of the nitrosamine. This step in the process cannot be observed in the case of
diazo-compounds derived from the substituted amines resembling para-nitraniline
in this respect.
The degree of temperature suitable for the reaction, in each case, depends upon
the presence, or absence, of substituting groups in the amido-compound and upon the
nature of such groups if present. Thus, the diazo-compounds from the non-
substituted primary amines or such as contain methyl or methoxyl-groups and the
like require heating with alkali at a temperature of about 100 to 120 degrees
Centigrade. The presence of one substituting halogen, carboxyl or sulpho-group
and the like in the diazo compound increases the readiness with which the reaction
takes place so that heating with caustic alkali on the boiling water-bath effects a
more ready conversion into the nitrosamine than in the case of the non substituted
amines. The same rules apply to tetrazo-compounds.
The new nitrosamine salts are all characterized by the property that when treated
with sufficient mineral acid they are converted into the corresponding diazo-
compounds. In some cases the free nitrosamine is formed as an intermediate

page_text: product. Further the nitrosamines give no dye when mixed with an alkaline
solution of sodium beta-naphtholate, but on saturating such a mixture with acetic
acid the diazo compound is formed which at once yields the corresponding azo-dye
with beta naphthol.
The following examples will serve to further illustrate the nature of the invention
but they are capable of variation without departure from the nature of the invention
and I do not bind myself thereto. The parts are by weight.
EXAMPLE 1.
Mix about ten parts of a solution containing twenty-five per cent. of diazo-
benzene chloride (or a corresponding quantity of some other salt of diazo-
benzene) with a solution of two hundred parts of caustic potash in about one
hundred parts of water. The potassium salt of diazo-benzene described by Griess
forms in the melt. It can be converted into the desired nitrosamine salt by heating
on the water-bath until no azo-dye is produced on mixing a sample of the melt with
a solution of sodium beta naptholate, but at this temperature the reaction proceeds
exceedingly slowly. For practical purposes therefore heat the melt to a temperature
of about one hundred and twenty degrees Centigrade for a few minutes when the
desired change with be brought about. Allow the melt to cool, the potassium salf
of phenyl-nitrosamine crystallizes out, separate this by filtration.
Obtained in this way the new compound is in the form of whitish-yellow needles
felted together which are soluble in alcohol and water, and which can be
recrystallized from the latter by dissolving therein and subsequently adding caustic
potash. On netralizing a solution with acetic acid a yellowish oil separates out
which readily decomposes, but if an excess of hydrochloric acid be used a solution
of diazo-benzene chloride is obtained.
Instead of caustic potash in the above example caustic soda can also be used.
As instances of diazo- and tetrazo-compounds which yield new nitrosamine-salts
on treatment in a manner similar to that described in the foregoing example I
mention those derived from ortho and para-toluidine, para-anisidine, alpha-
naphthylamine, benzidine and the like. In all these cases the best temperature is
about 110 to 120 degrees Centigrade and the end of the reaction can be determined
by the test with sodium beta-naphtholate described. In most cases a smaller
proportion of alkali can be taken than above described in the case of diazo-benzene.
EXAMPLE 2.
Mix about ten parts of a solution containing twenty-five per cent. of para-
bromo-diazo benzene chloride with about seventy parts of a solution of caustic
potash (containing fifty per cent. KHO). A yellow amorphous precipitate
forms. Heat on the water-bath. From the yellow solution which results crystals
of the potassium compound described by Griess separate out as the temperature
rises to about eighty-five degrees Centigrade. Continue boiling until the test with
sodium beta-naphtholate is satisfied. Allow to cool. The nitrosamine salt separates
Collect in the usual way.
out.
The diazo-compound of para-amido-benzoic acid may be mentioned as an instance
of another compound which can be treated in a manner similar to that described in
the foregoing Example 2.
Dated the 16th day of February 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, Agents.

page_text: +
The Manufacture and Production of New Nitrosamine Compounds
suited for Use in the Preparation of Diazo-compounds.
I, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of London
Gentleman do hereby declare the nature of this invention (which has been
communicated to me from abroad by The Badische Anilin & Soda Fabrik of
Ludwigshafen-on-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 a further developement of the invention the nature
of which is described in the Specification of my application for Letters Patent
No. 20605 of 1893.
In the said Specification the conversion of certain diazo-compounds into new
nitrosamines and the useful application of these bodies are described. The diazo-
compounds which are in the said Specification stated to be capable of use are.
principally those derived from such aromatic amido compounds as contain a
substituting acid group or substituting acid groups such for instance as one or more
nitro groups, two or more halogens in the same benzene or naphthalene residue with
or without sulpho groups and the like.
The present invention relates to modifications in the processes described in the'
aforesaid Specification with the object of applying the said processes to a large
number of diazo-compounds not included in the definition of the foregoing paragraph
namely such as contain no substituting acid group or groups or only one halogen,.
or sulpho or carboxyl groups. Under diazo compounds containing one halogen
I include the diazotised products that is the tetrazo compounds of such diphenyl
derivatives as contain one halogen in each benzene residue. By the aid of the said
modified process it is possible to obtain from these diazo-compounds also, new
nitrosamines capable of useful industrial application in the production of azo-dyes
on, or in the presence of, the goods to be dyed and in other ways. In this way the
number of shades of colour obtainable by the use of the new nitrosamine compounds
is largely increased and in respect to other qualities also the dyer is afforded a
wider range of choice.
Thus on.
The principal variation in this process is in point of temperature.
treating the diazo compounds used according to this invention with a caustic alkali
or the like at the ordinary temperature no conversion into the corresponding nitros-
amine can be effected, but my foreign correspondents have found that by effecting
the treatment at a suitable elevated temperature, which varies in different cases,
the new nitrosamines can readily be obtained.
Another point of difference in the reaction according to the present invention is
the production of the alkali-salt of the diazo compound as an intermediate product
before the formation of the nitrosamine. This step in the process cannot be
observed in the case of diazo compounds derived from the substituted amines
resembling para nitraniline in this respect and included in the aforesaid Specification
No. 20605 of 1893.
The degree of temperature suitable for the reaction, in each case, depends upon
the presence or absence of substituting groups in the amido compound and upon the
nature of such groups if present. Thus, the diazo compounds from the non-
substituted primary amines or such as contain methyl or methoxyl-groups and the
like require heating with alkali at a temperature of about 100 to 120 degrees
Centigrade or higher. The presence of one substituting halogen, carboxyl or sulpho
group, and the like in the diazo compound increases the readiness with which the

page_text: reaction takes place so that heating with caustic alkali on the boiling water bath
effects a more ready conversion into the nitrosamine than in the case of the non-
substituted amines. The same rules apply to tetrazo compounds. Thus tetrazo-
diphenyl can be converted into the nitrosamine like diazo benzene or diazo
naphthalene, whilst tetrazo-dibromo-diphenyl behaves in a manner similar to diazo-
mono-brom-aniline..
The new nitrosamine salts are all characterized by the property that when treated
with sufficient mineral acid they are converted into the corresponding diazo
compounds. In some cases the free nitrosamine is formed as an intermediate product.
Further the nitrosamines give no dye when mixed with an alkaline solution of sodium
beta-naphtholate, but on saturating such a mixture with acetic acid the diazo
compound is formed which at once yields the corresponding azo dye with beta
naphthol.
The following examples will serve to further illustrate the nature of the invention
but they are capable of variation without departure from the invention and I do not
bind myself thereto. The parts are by weight.
EXAMPLE 1.
Mix about ten parts of a solution containing twenty-five per cent. of diazo
benzene chloride (or a corresponding quantity of some other salt of diazó-
benzene) with a solution of two hundred parts of caustic potash in about one
hundred parts of water. The potassium salt of diazo-benzene described by Griess
forms in the melt. It can be converted into the desired nitrosamine salt by heating
on the water-bath, until no azo-dye is produced on mixing a sample of the melt with
a solution of sodium beta-naphtholate, but at this temperature the reaction proceeds
exceedingly slowly. For practical purposes therefore heat the melt to a temperature
of about one hundred and twenty degrees Centigrade for a few minutes when the
desired change will be brought about. Allow the melt to cool, the potassium salt
of phenyl-nitrosamine crystallizes out; separate this by filtration.
Obtained in this way the new compound is in the form of whitish-yellow needles
felted together, which are soluble in alcohol and water and which can be recrystallized
from the latter by dissolving therein and subsequently adding caustic potash. If
an excess of hydrochloric acid be added to a solution of the nitrosamin salt diazo-
benzene chloride is obtained.
Instead of caustic potash in the above example caustic soda can be used.
As instances of diazo- and tetrazo compounds which yield new nitrosamine salts on
treatment in a manner similar to that described in the foregoing example I mention
those derived from ortho and para-toluidine, para anisidine, alpha and beta-
naphthylamine, benzidine and the like. In all these cases the best temperature is
about 110 to 120 degrees Centigrade, or even higher and the end of the reaction
can be determined by the test with sodium beta-naphtholate described.
In most
cases a smaller proportion of alkali can be taken than above described in the case of
diazo benzene.
EXAMPLE 2.
Mix about ten parts of a solution containing twenty-five per cent. of para-
bromo-diazo-benzene chloride with about seventy parts of a solution of caustic
potash (containing fifty per cent. KHO). A yellow amorphous precipitate forms.
Heat on the water-bath. From the yellow solution which results crystals of
the potassium compound described by Griess separate out as the temperature
rises to about eighty five degrees Centigrade. Continue beating until the test with
sodium beta-naphtholate is satisfied. Allow to cool. The nitrosamine salt separates
Collect in the usual way.
out.
The diazo compound of para-amido-benzoic acid may be mentioned as an instance
of another compound which can be treated in a manner similar to that described
in the foregoing Example 2.

page_text: 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
1. The manufacture of nitrosamines from the diazo and tetrazo-compounds
hereinbefore defined by heating them with a caustic alkali.
2. The manufacture of the nitrosamines in the manner herein described in the
examples.
3. As new articles of manufacture the new nitrosamines such as can be obtained
substantially as hereinbefore described and claimed.
Dated this 2nd day of November 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, Agents.