Improvements in the Manufacture of Colouring Matters and Materials therefor.
Year: 1894

page_text: Date of Application, 12th Mar., 1894
Complete Specification Left, 21st Nov., 1894-Accepted, 22nd Dec., 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by Messrs. WIRTH & Co., of Frankfort-on-the-
Main, in the Empire of Germany, acting as Agents of A. Leonhardt & Co.,
of Mühlheim, near Frankfort-on-the-Main, in the Empire of Germany, Aniline
Colour Manufacturers.]
Improvements in the Manufacture of Colouring Matters and
Materials therefor.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention to be as follows:-
This invention relates to the production of new nitroso derivatives of metaamido-
phenol or metaamidocresols or of their monoalkylated derivatives and to the
production of colouring matters derived from such nitroso derivatives.
I have found that the known methods of nitrosation (viz. working with free or
chemically bound nitrous acid) cannot be employed with unsubstituted metaamido-
phenol or metaamidocresol, because in this instance only diazo or azo compounds
are formed. But I have discovered that acid derivatives of metaamidophenols,
such as acetylamidophenol may be converted into nitroso compounds by the action
of nitrous acid (nitrosamines being apparently formed in the first stage), the said
nitroso compounds yielding the nitroso derivatives of the metaamidophenols them-
selves by saponification.
When nitroso derivatives of monoalkylated métaamidophenols are to be produced,
two methods can be employed according to my experiments. (1) Reacting with
nitrous acid in a strongly acidulated solution on the monoalkylated amidophenols,
and thus transforming the nitrosamines produced in the first stage into the
nitroso compounds. (2) Reacting with metallic nitrites on the acid salts of the
monoalkylated metaamidophenols in the absence of free mineralic acid (this way is
analogous to the one described in my Letters Patent 1390 and 2114".
The thus obtained nitroso derivatives, mono-nitrosometaamidophenols or mono-
nitrosomonoalkyl-metaamidophenols, may be directly employed for dyeing purposes
and when heated with aromatic amines or metaamidophenols or their substitutes
preferably in presence of a dissolving or distributing agent yield basic colouring
matters suitable for dyeing mordanted cotton.
Instead of saponifying the nitrosated acid derivatives of metaamidophenols, as
stated above and then forming dyestuffs from the saponified products, dyestuffs can
be obtained direct from the nitrosated acid derivatives and may be saponified after-
wards. The so-obtained saponified dyestuffs are identical with those obtained in
the manner indicated first.
1001

page_text: Improvements in the Manufacture of Colouring Matters and
Materials therefor.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention 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 of new nitroso derivatives of metaamido-
phenol or metaamidocresol or their monoalkylated derivatives and to the production
of colouring matters from such nitroso derivatives.
In order to obtain the nitroso derivatives of metaamidophenol or metaamido-
cresol, these compounds are first transformed into their acid derivatives, best into
the acetyl derivatives (which are produced as is well known by heating metaamido-
phenol or metaamidocresol with glacial acetic acid); these latter when treated
with nitrous acid in the presence of mineralic acid (hydrochloric acid giving the
best results) yield new nitroso acid derivatives, from which the acid (acetyl) group
can be removed by saponification. Thus for instance, when metaamidophenol is to
be transformed into nitrosometaamidophenol, this transformation is effected in the
following way:

page_text: solutions (hydrochloric acid being employed by preference) whereby the trans-
formation referred to above is effected at once. Another method for the production
of such nitrosomonoalkylmetaamidocresols consists in reacting with metallic nitrites
on the acid salts of the monoalkylated metaamidocresols in the absence of further
mineralic acid. This second method is the better one, and is quite analogous to the
one described in former Letters Patent No. 1390 page 2 lines 25-29; and
No. 21154 page 2, lines 1-6.
The thus obtained mononitrosometaamidophenol or mononitrosometaamido-p-
cresol or nitrosomonoalkylmetaamido-p-cresols when combined with suitable aro-
matic amines in the presence of mineralic acid and a suitable dissolving or
distributing agent, (preferably employing about 3 molecular proportions of the
nitroso compound to two molecular proportions of the amine) yield blue to violet
basic colouring matters suitable for dyeing mordanted cotton. And it has further
been found that also the nitroзoacetylmetaamidophenol or nitrosoacetylmeta-
amido-p-cresol can be combined with suitable aromatic amines, the dyestuffs thus
produced losing the acetyl-group by saponification, forming dyestuff's identical with
those obtained from non-acetylated nitrosometaamidophenol or nitrosometaamido-p-
cresol.
The following directions will show in what manner the present invention is best
put into practice, the parts being given by weight.
FIRST. PRODUCTION OF
MONONITROSOMETAAMIDOPHENOL
NITROSOMETAAMIDOCRESOL.
OR MONO-
(A) Nitrosation.-5 parts of acetylmetaamidophenol are dissolved in about
15 parts of hot water. The obtained solution is introduced into a mixture of
30 parts of concentrated hydrochloric acid and 30 parts of ice. To this solution
(from which a part of the acetylmetaamidocresol generally crystallizes out) is
added in the cold state a solution of 2.5 parts of sodium nitrite in about 7 parts of
water, whereby a crystalline yellow precipitate consisting of mononitrosoacetyl-
metaamidophenol separates, which after a short standing is filtered and well washed
with cold water.
°
In the same manner nitrosoacetylmetaamido-p-cresol or nitrosoacetylmetaamido-
orthocresol is obtained. Concerning the latter it is especially stated that acetyl-
metaamido-ortho-cresol is only slightly soluble in hot water; therefore it is best
first dissolved in the sufficient quantity of caustic soda lye of 5% at a moderately
elevated temperature and then precipitated in a finely divided state by pouring the
solution into the above mentioned mixture of hydrochloric acid and ice. The thus
obtained precipitate, when nitrosated is gradually transformed into the nitroso
derivative, which can be recognized by the change of colour and by testing a
sample of the precipitate with a solution of carbonate of soda in which it must
completely dissolve with a yellow colour.
These nitrosoacetyl derivatives are soluble in the cold state in dilute caustic
alkalies or carbonate of sodium. They can be purified by crystallizing out of
spirit.
(B) Saponification.—The saponification is effected by means of caustic alkalies
or mineralic acids.
EXAMPLES:
1. The uitroso derivatives obtained from 2-6 parts of acetylmetaamidophenol is
dissolved in 10 parts of water and 6 parts of caustic soda lye of 40° Be. and the
solution is heated up to about 70° C. during about one hour, until a sample worked
up as indicated hereinafter, shows that saponification has taken place. The mass
is diluted with cold water, then acidulated with hydrochloric acid, the solution
is filtered from any residue and precipitated with acetate of sodium and common

page_text: salt, whereby nitrosometaamidophenol separates in the form of a reddish
crystalline powder. It can be purified by mixing with concentrated hydrochloric
acid whereby the chlorhydrate which is only slightly soluble in the strong acid
separates and is filtered off and transformed again, if desired, into the free
nitroso base.
2. One part of nitrosoacetylmetaamido-p-cresol is heated with 5 parts of
concentrated hydrochloric acid up to about 50° C. At first dissolution takės
place, but after standing some time and cooling the chlorhydrate of nitrosometa-
amido-p-cresol, which is only slightly soluble in the concentrated acid separates
from the solution and is filtered and pressed. A further purification is effected
either by dissolving in cold water and salting out with common salt; or by trans-
forming the chlorhydrate into the free base (with acetate of sodium) which can be
crystallized out of spirit.
3. One part of dried nitrosoacetylmetaamido-ortho-cresol is dissolved in the cold
state in 6 parts of concentrated sulphuric acid and the solution is left to itself
during several hours at a moderately elevated temperature, until a sample dissolves
easily in water and when worked up in the manner hereinafter described indicates
the end of the saponification. The mass is poured on ice and the greater part of
the acid is neutralized by adding caustic soda lye in the cold state whereby the
nitrosoamido-ortho-cresol separates in the form of a red crystalline precipitate.
The nitrosoamidophenols or cresols obtained in such a way show basic and acid
properties, being soluble in dilute caustic soda lýe with an intensely yellow colour
and in dilute mineralic acids with a less intense yellow colour. The basic properties
of nitrosometaamido-ortho-cresol are not of a high degree inasmuch as the acid
salts easily dissociate with water. The free nitroso bases can be crystallized out of
spirit and are somewhat soluble in water (especially nitrosoamidophenol), the
watery solution can be precipitated with common salt.
SECOND. PRODUCTION OF MONONITROSOMONOALKYLMETAAMIDO-P-CRESOL.
1. One part of monoethylmetaamido-p-cresol is dissolved in 20 parts of hydro-
chloric acid of 20% and to the solution is gradually added in the cold state a
watery solution of a molecular quantity of nitrite of sodium, when the chlorhydrate
of nitrosomonoethylmetaamido-p-cresol will separate in small yellowish crystals.
2. Dissolve 15 parts of pure monoethylmetaamidocresol in 60 parts of water
and 12 parts of hydrochloric acid of 30%. Add to this solution, which is well
cooled with ice, a solution of 0.8 parts of sodium nitrite in 7 parts of water.
When
the free nitroso base has completely separated, filter and press.
The melting point of the methyl derivative has been found to be at 199° C., of
the ethyl derivative at 150° C. Both nitroso compounds dissolve in dilute mineralic
acid and in dilute caustic soda lye.

page_text: EXAMPLES:
1st. Mix 27 parts of mononitrosomonoethylamidocresol with 17 parts of ethyl-
alphanaphthylamine, 30 parts of hydrochloric acid of 30% and 80 parts of spirit.
Heat at the reflux cooler until the nitroso compound has disappeared. Add about
500 parts of hot water, purify the solution by adding about 30 parts of acetate of
sodium, filter and precipitate the colouring matter from the cooled solution with
common salt and chloride of zinc.
2nd. A mixture of 13 parts of nitrosomonomethylmetaamido-p-cresol, 8 parts of
metaamidodimethylparatoluidine, 15 parts of hydrochloric acid of 30% and
30 parts of spirit is heated at the reflux cooler until no more nitroso compound can
be ascertained and the solution has assumed a pure blue tint.
The whole is then diluted with about 400 parts of hot water, the solution is
purified with about 15 parts of acetate of sodium and the dyestuff is precipitated
from the filtered and cooled solution with common salt and chloride of zinc.
3rd. Heat as stated under the foregoing examples a mixture of 2.2 parts of
nitrosomonomethylmetaamidocresol, 1.2 parts of monomethylmetaamidocresol,
26 parts of bydrochloric acid of 30% and 15 parts of spirit. The colouring
matter crystallizes out on cooling and is filtered and washed with spirit.
FOURTH. PRODUCTION OF COLOURING MATTERS FROM NITROSOMETAAMIDO.
PHENOL OR NITROSOMETAAMIDO-P-CRESOL AND AROMATIC AMINES.
Amongst aromatic amines the process has been especially tried with the
following: Alphanaphthylamine, ethylalphanaphthylamine, metaamidodimethylpara-
toluidine, tetramethylmetaphenylenediamine, metaamidoparacresol (CH.: NH,:
OH 1:2:4). The colouring matters obtained from nitrosoamido-p-cresol have
proved to be identical with those obtained from the azo derivatives of amido-p-
cresol according to former Letters Patent No. 15080" under third and fourth.
=

page_text: 30. parts of spirit. The fluid quickly assumes a red tint and the acetylated
colouring matter separates in crystals and is isolated by filtration.
It dyes
mordanted cotton in red shades and is not fast against alkalies.
In order to saponify this colouring matter, heat the same with about 10 parts of
concentrated sulphuric acid during a short time on the water bath, until a sample
dissolves in water with a pure violet colour. Pour the whole into ice water and
filter the saponified dyestuff which has separated.
2nd. Replace in the foregoing example a-naphthylamine by the equivalent
quantity of metatoluylenediamine. Operate in an analogous manner. A dyestuff
will finally be obtained which dyes mordanted cotton in violet shades.
3rd. Heat at the reflux cooler a mixture of 3 parts of tetramethylmetaphenylene-
diamine, 6 parts of nitrosoacetylmetaamido-p-cresol, 3.5 parts of hydrochloric acid
of 30% and 40 parts of spirit. When the solution has assumed a red tint, add
24 parts of concentrated hydrochloric acid and boil until the solution becomes of a
violet colour. Dilute with hot water, remove impurities by adding the necessary
quantity of acetate of sodium, and precipitate the saponified dyestuff from the
filtered and cooled solution with common salt.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
1. The production of mononitrosometaamidophenol or mononitrosometaamido-
orthocresol or mononitrosometaamidoparacresol by the herein described process,
which consists in nitrosating acetylmetaamidophenol or acetylmetaamidoorthocresol
or acetylmetaamidoparacresol and splitting off afterwards the acetyl groups, sub-
stantially as hereinbefore described.
2. The production of mononitrosoacetylmetaamidophenol or mononitrosoacetyl-
metaamidoorthocresol or mononitrosoacetylmetaamidoparacresol by the herein
described process which consists in nitrosating acetylmetaamidophenol or acetyl-
metaamidoorthocresol or acetylmetaamidoparacresol, substantially as hereinbefore
described.
3. The production of mononitrosometa amidophenol or mononitrosometaamido-
orthocresol or mononitrosometaamidoparacresol by the hereinbefore described
process which consists in saponifying the corresponding acetyl derivatives, sub-
stantially as hereinbefore described.
4. Mononitrosometaamidophenol or mononitrosometaamidoorthocresol or mono-
nitrosometaamidoparacresol produced substantially as hereinbefore described.
5. The acetyl derivatives of the nitroso derivatives mentioned under Claim 4
produced substantially as hereinbefore described.
6. The production of mononitrosomonomethylmetaamidoparacresol or mono-
nitrosomonoethylmetaamidoparacresol by the hereindescribed processes which
consist in
?
T.
7.
(a) Treating monomethylmetaamidoparacresol or monoethylmetaamidopara-
cresol with nitrous acid in strongly acidulated solutions substantially, as
herein before described.
(b) Reacting with metallic nitrites on the acid salts of monomethylmetaamido-
paracresol or monoethylmetaamidoparacresol in the absence of further
mineralic acids, substantially as hereinbefore described.
Mononitrosomonomethylmetaamidoparacresol or mononitrosomonoethylmeta-
amidoparacresol produced substantially as hereinbefore described.
8. The production of violet to blue basic colouring matters by the herein-
described process which consists in
mono-
(a) Reacting with mononitrosomonomethylmetaamidoparacresol or
nitrosomonoethylmetaamidoparacresol on the aromatic amines enumerated
in the Specification under third, substantially as hereinbefore described..

page_text: (b) Reacting with mononitrosometaamidophenol or mononitrosometaamido-
paracresol on the aromatic amines enumerated in the Specification under
fourth, substantially as hereinbefore described.
(c) Reacting with the acetyl derivatives of mononitrosometaamidophenol or
mononitrosometaamidoparacresol on the aromatic amines mentioned in the
Specification under fifth and saponifying the acetylated dyestuffs obtained in
the first stage, all substantially as hereinbefore described.
9. The violet to blue basic colouring matters produced substantially as herein-
before described.
Dated this 21st day of November 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.