Improvements in the Production of Para-nitro-phenol and Ortho-nitro-toluene-para-sulphonic Acid.
Year: 1895

page_text: Date of Application, 17th Dec., 1895
Complete Specification Left, 17th Sept., 1896-Accepted, 21st Nov., 1896
PROVISIONAL SPECIFICATION.
Improvements in the Production of Para-nitro-phenol and
Ortho-nitro-toluene-para-sulphonic Acid.
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU
RHONE, anct. GILLIARD P. MONNET & CARTIER, of Lyons, France,
Manufacturers.
I, GEORGE BELOE ELLIS of the Firm of J. C. Mewburn & Ellis of 55
and 56 Chancery Lane, in the County of London, Chartered Patent Agents, do
hereby declare the nature of this invention to be as follows:-
This invention has reference to the production of para-nitro-phenol and ortho-
nitro-toluene-para-sulphonic acid.
The simple nitro derivatives of phenol, especially para-nitro-phenol, possess very
great technical value as the starting point for the synthetical production of
numerous dyes and other compounds employed in the arts and in medicine and for
these purposes it is necessary to obtain them as free from isomerides as possible.
Direct nitration of phenol always produces the two isomerides, ortho and para-
nitro-phenol, in proportions varying according to the conditions of nitration. Up
to the present time it has been impossible to obtain in this manner one or the other
of the isomerides exclusively, and the operation is moreover always accompanied
by the formation of tarry products which are of little or no value.
According to the present invention phenol is combined with an aromatic
sulpho-chloride, preferably with para-toluene-sulpho-chloride, in the presence of
alkali, whereby an ester is obtained which can easily be nitrated without
production of tarry products and with the exclusive formation of a para-nitro-
phenol derivative. The para-toluene-sulphonic ester of phenol is then nitrated.
and a nitro group is thus introduced into the toluene radical in the ortho position
simultaneously with the nitration of phenol in the para position, and the para-
nitro-phenol ester of ortho-nitro-toluene-para-sulphonic acid is formed.
nitrated ester is subsequently subjected to hydrolysis by means of aqueous
solutions of caustic alkalies and the para-nitro-phenolate of the alkali together
with the alkali salt of ortho-nitro-toluene-para-sulphonic acid is thereby obtained.
From these salts para-nitro-phenol and ortho-nitro-toluene-para-sulphonic acid
are easily isolated in a state of purity. The latter may be employed in the
nanufacture of vanillin.
This
The chemical reactious which take place in performing these operations may:
be represented by the following equations:-

page_text: usual way by dissolving sodium phenolate in five times its weight of water at
80° Centigrade and adding the theoretical quantity of para-toluene-sulpho-chloride,
stirring vigorously the whole time. On cooling the ester is separated in a pure
state in theoretical quantity.
The nitration of the para-toluene-sulphonic acid phenol-ester can be effected
by making an intimate mixture of 100 kilos. of para-toluene-sulphonic acid phenol
ester with 100 kilos. of potassium nitrate and adding the mixture in small
quantities at a time, to 1000 kilos. of sulphuric acid (66° B.) the temperature
being maintained at 15° C. throughout the operation by any suitable means of
cooling the mass.
When the reaction is finished the nitrated product is separated from the
sulphuric acid by filtration or centrifugal action, and well washed with water.
Under these conditions only the dinitrated product indicated above is formed,
namely, ortho-nitro-toluene-para-sulphonic-acid-para-nitro-phenol-ester, which melts
at 115° Centigrade.
The hydrolysis of the nitrated ester can be effected by suspending the nitrated
product in its own weight of caustic soda solution of 36° B., which is heated at 100° C.
until complete solution is effected and then allowed to cool. The para-nitro-phenolate
of sodium crystallises out and may be separated by filtration from the ortho-nitro-
toluene-para-sulphonate of sodium which remains in solution. The respective
products, para-nitro-phenol and ortho-nitro-toluene-para-sulphonic acid, can be
liberated from their sodium salts by means of dilute mineral acids.
Dated this 17th day of December 1895.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, Loudon, Chartered Patent Agents.
Improvements in the Production of Para-nitro-phenol and
Ortho-nitro-toluene-para-sulphonic Acid.
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU
RHÔNE, anct. GILLIARD P. MONNET & CARTIER, of Lyons, France,
Manufacturers.
I, GEORGE BELOE ELLIS of the Firm of J. C. Mewburn & Ellis of 55
and 56 Chancery Lane, in the County of London, Chartered Patent Agents,
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 has reference to the production of para-nitro-phenol and ortho-
nitro-toluene-sulphonic acid.
The simple nitro derivatives of phenol, especially para-nitro-phenol, possess very
great technical value as the starting point for the synthetical production of
numerous dyes and other compounds employed in the arts and in medicine, and for
these purposes it is necessary to obtain them as free from isomerides as possible.
Direct nitration of phenol always produces the two isomerides, ortho- and para-
nitro-phenol, in proportions varying according to the conditions of nitration. Up
to the present time it has been impossible to obtain in this manner one or the other
of the isomerides exclusively, and the operation is moreover always accompanied
by the formation of tarry products which are of little or no value.
According to the present invention phenol is previously combined with an
aromatic sulpho-chloride, preferably with para-toluenesulphochloride, in the
presence of an alkali, whereby an ester is obtained which can easily be nitrated

page_text: without production of tarry products and with the exclusive formation of a
para-nitro-phenol derivative."
The para-toluene-sulphonic ester of phenol is then nitrated and a nitro group
is thus introduced into the toluene radicle in the ortho position simultaneously with
the nitration of phenol in the para position, and the para-nitro-phenol ester of
ortho-nitro-toluene-para-sulphonic acid is formed. This di-nitrated ester is
subsequently subjected to hydrolysis by means of aqueous solutions of caustic
alkalies and the para-nitro-phenolate of the alkali together with the alkali salt of
ortho-nitro-toluene-para-sulphonic acid is thereby obtained. From these salts para-
nitro-phenol and ortho-nitro-toluene-para-sulphonic acid are easily isolated in a
state of purity. The latter may be employed in the manufacture of vanillin.
The chemical reactions which take place in performing these operations may be
represented by the following equations:-
By the saponification of this product with the aid of caustic alkalies it could be
split up into para-nitro-phenol and benzene-sulphonic acid.
This method has not however found industrial employment because the saponifica-
tion of the para-nitro-phenol-benzene-sulphonic-acid-ester is very difficult and not only
requires the employment of a large excess of alkali in very concentrated solution
but also the employment of a temperature at which the products of the reaction
are partially decomposed.
These difficulties are overcome according to the present invention by a more
energetic nitration of the ester than Schiaparelli employed, whereby it has been
discovered that a di-nitrated product may be obtained of the composition illustrated;
by the formula
which can be easily saponified, even at the temperature of the water bath and
with caustic alkalies even in very dilute solution. Moreover the products of
saponification, para-nitro-phenol and the corresponding nitro-sulphonic acid, are.
obtained in quantities corresponding to theory.
It has been discovered that all the aromatic sulphochlorides can be employed in
the above manner in the manufacture of para-nitro-phenol but the para-toluene-
sulphochloride has been more particularly used because it is obtained in large
quantities as a bye product of another manufacture. By combination with

page_text: phenol in the presence of alkali the para-toluene-sulphonic ester of phenol is
obtained.
In carrying out the manufacture of para-nitro-phenol according to this invention
other aromatic sulphochlorides, such as benzene-sulphochloride, ortho-toluene-
sulphocholoride, a-naphthalene-sulphochloride, ẞ-naphthalene-sulphochloride, etc.,
may be employed in the same manner, save that different proportions by weight of
the sulphochlorides and their compounds must be used according to their molecular
weight.
EXAMPLE I.
The phenol ester of paratoluene-sulphonic acid can be prepared in the usual way
by dissolving sodium phenolate in five times its weight of water at 80° C. and adding
the theoretical quantity of paratoluenesulphiochloride, stirring vigorously the whole
time. Or it may be preferable to dissolve 100 kilos. phenol and 42 kilos. caustic
soda in 1000 litres of water, heat with a steam jet, and add gradually 210 kilos. of
paratoluene-sulphochloride. When all the sulphochloride has been added the
heating is continued until no odour of sulphochloride remains. The mass is then
allowed to cool, the ester filtered off, washed freely with water and dried. It melts
about 94° or 95° C.
The nitration of the paratoluenesulphonic-acid-phenol-ester can be effected by
making an intimate, finely-powdered mixture of 100 kilos. of paratoluene-sulphonic-
acid-phenol-ester with 100 kilos. of potassium nitrate and adding the mixture in
small quantities at a time to 1000 kilos. of sulphuric acid (66° B.), the temperature
being maintained about 15° C. throughout the operation by any suitable means of
cooling the mass. The nitrate of potassium can be substituted by the corresponding
quantity of nitric acid in concentrated solution.
When the reaction is finished the nitrated product is separated from the sulphuric
acid by filtration or centrifugal action and well washed with water. Under these
conditions only the dinitrated product indicated above is formed, namely ortho-
nitro-toluene-para-sulphonic-acid-para-nitro-phenol-ester, which, after drying and
recrystallisation from benzene, melts at 115° C.
The hydrolysis of the di-nitrated ester can be effected by suspending the nitrated
product in its own weight of caustic soda solution of 36° B., or to 100 kilos. di-nitro
ester 30 kilos. caustic soda in aqueous solution, which is heated to 100° C. until
complete solution is effected and then allowed to cool. The para-nitro-phenolate
of sodium crystallises out and may be separated by filtration from the ortho-
nitro-toluene-para-sulphonate of sodium which remains in solution, The respective
products, para-nitro-phenol and ortho-nitro-toluene-para-sulphonic acid, can be
liberated from their sodium salts by means of dilute mineral acids.
is obtained, which melts at 132 to 133° C. and may be easily hydrolysed by caustic
alkalies, yielding meta-nitro-benzene-sulphonic acid and para-nitro-phenol.

page_text: to those specified in Example I, the phenol ester of ortho-toluene-sulphonic acid
can be obtained; it melts at 52° C. By nitration of this compound a dinitrated
product can be obtained the composition of which may be expressed by the
formula
phenol, the
Dy causing a-napntaleme supnochioride to act on
a-naphtalene-sulphonic acid can be obtained. It melts at 75° C. On nitration a
mixture of various para-nitro-phenol esters of different nitrated a-naphtalene-
sulphonic acids are obtained which have not been isolated. On hydrolysis the
mixture yields para-nitro-phenol and a mixture of several nitro a-naphtalene-
sulphonic acids.
EXAMPLE V.
By the action of ẞ-naphtalene sulphochloride on phenol, the phenol ester of
B-naphtalene-sulphonic acid can be obtained. It inelts at 98° to 99° C. By
Ditration under the conditions given in Example it is transformed into a
nitrated product which upon hydrolysis with caustic soda yields para-
nitro-phenol and different nitrated derivatives of ẞ-naphtalene-sulphonic acid.
The nitrated esters in Examples IV and V are not hydrolysed so easily as the
foregoing.
Having now particularly described and ascertained the nature of this invention
as communicated to me and in what manner the same is to be performed, I declare
that what I claim is :-
1. The manufacture of paranitrophenol by the combination of phenol with a
sulphochloride of an aromatic hydrocarbon, e.g., benzene sulpho-chloride, ortho- or
para-toluenesulphochloride, a- or ß-naphtalene-sulphochloride etc., in the presence
of alkali, and conversion of the resulting ester into di-nitrated or poly-nitrated
products which can be easily saponified by caustic alkalies in aqueous solution, and
saponification of the same substantially as described.
2. The manufacture of ortho-nitro-toluene-para-sulphonic acid by combination of
para-toluene-sulpho-chloride with phenol in presence of alkali, nitration of the
resulting ester to a dinitrated product, namely the para-nitro-phenol ester of ortho-
nitro-toluene-para-sulphonic acid, which melts at 115° C., and saponification of the
dinitrated ester by means of caustic alkali in aqueous solution, substantially
as described.
3. The process whereby para-nitrophenol and ortho-nitro-toluene-para-sulphonic
acid are produced simultaneously by nitration of the phenol ester of paratoluene-
sulphonic acid into a dinitrated product and its saponification by means of caustic
alkali in aqueous solution, and the separation of the two dissociation products in
the usual way, substantially as described.
4. As novel products the phenol esters of ortho-tolueue-sulphonic acid, a-naphta-
lene-sulphonic acid and ẞ-naphtalene-sulphonic acid, and the para-nitro-phenol
esters of meta-nitro-benzene-sulphonic acid, ortho-nitro-toluene-para-sulphonic acid
and para-nitro-toluene-ortho-sulphonic acid obtained as intermediate products
in the manufacture of para-nitro-phenol, substantially as described.

page_text: 5. The herein described process of nitration of phenol esters of aromatic sulpho
acids whereby dinitrated or poly-nitrated esters may be obtained which are easily
saponified by means of caustic alkalies in aqueous, solution.
Dated this 17th day of September 1896.
J. C. MEW BURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.