The Manufacture and Production of Derivatives of Diphenylethane and of Diphenylethylene
Year: 1897

page_text: Date of Application, 27th Feb., 1897
Complete Specification Left, 23rd Nov., 1897-Accepted, 24th Dec., 1897
.
PROVISIONAL SPECIFICATION.
"The Manufacture and Production of Derivatives of Diphenylethane
and of Diphenylethylene."
We, ARTHUR GEORGE GREEN, F.I.C., F.C.S., of 13 Kings Drive, Heaton Moor,
near Stockport, and ANDRÉ RAOUL WAHL, of 331 Ashton New Road, Clayton, near
Manchester, Consulting Chemists, and THE CLAYTON ANILINE CO. LIMITED, of Clayton
aforesaid, do hereby declare the nature of this invention to be as follows:-
We have discovered that by oxidation of paranitrotoluene sulphonic acid in alkaline
solution two molecules undergo condensation with production of dinitro-
diphenylethane disulphonic acid,
-
NO₂CH.(SO,H)CH: CHCН(SO₂H)NO..
These two products are obtained either in admixture with each other or separately
according to the quantity of the oxidising agent employed and the conditions under
which the reaction is performed.
In general dinitrodiphenylethane disulphonic acid is the chief or sole product
when a quantity of oxidising agent is employed equal to one atom of oxygen for
every two molecules of paranitrotoluene sulphonic acid. On the other hand
dinitrodiphenylethylene disulphonic acid is the chief or sole product when the
oxidising agent is employed in quantity equivalent to two atoms of oxygen for two
molecules of paranitrotoluene sulphonic acid. For the production of the former
compound it is moreover advantageous to use a large excess of caustic alkali in order
that the product which is sparingly soluble in the alkali may be precipitated and so
protected from further change. For the production of the latter compound on the
other hand a smaller quantity of caustic alkali is necessary. In place of
paranitrotoluene sulphonic acid there may be employed with like effect the unstable
safranine-red compound which is formed from the latter by the action of caustic
alkalies and constitutes the first stage of the "curcumine" reaction.
The dinitrodiphenylethylene disulphonic acid can also be obtained by oxidation of
dinitrodiphenylethane disulphonic acid whether the latter has been prepared in the
manuer already described or by any other method. Inversely the dinitrodiphe-
nylethylene disulphonic acid can be converted into dinitrodiphenylethane disulphonic
acid by submitting it to reduction in alkaline solution when it is converted into the
safranine-red body already mentioned which by oxidation gives dinitrodiphenylethane
disulphonic acid.
For the above mentioned reactions any suitable oxidising agent capable of acting
in alkaline solution may be employed such as sodium hypochlorite, sodium peroxide,

page_text: lead peroxide, potassium ferricyanide ammonium persulphate and the like, but we
have found that the most suitable for the purpose is sodium hypochlorite..
The oxidation may also be brought about by submitting paranitrotoluene sulphonic
acid to electrolysis at the anode pole in alkaline solution.
By reduction in acid solution dinitrodiphenylethane disulphonic acid is converted
into diamidodiphenylethane disulphonic acid
The reduction of the dinitro compounds to the diamido compounds can be accorn-
plished by any of the usual acid reducing agents such as stannous chloride, zinc dust,
iron, and the like.
Both the nitro compounds and the corresponding amido compounds are employed
as intermediate bodies in the manufacture of colouring-matters.
The following examples are given to illustrate the general method of carrying out
our Invention into practice but we do not limit ourselves to the precise details.
The
Example No. 1. 100 lbs of sodium paranitrotoluene sulphonate are dissolved in 100
gallons of warm water. 50 gallons of caustic soda lye of 30% NaOH are added and
whilst the temperature is kept at about 40°-50° centrigrade, 22 gallons of sodium
hypochlorite solution containing 7% of available chlorine are slowly run in. When
all the hypochlorite has disappeared 200 gallons of cold water are added and the
precipitated sodium salt of dinitrodiphenylethane disulphonic acid is filtered off. It
is purified by dissolving in dilute hydrochloric acid and adding strong hydrochloric
acid to the hot solution when on cooling the free sulphonic acid crystallises out in
large colourless micaceous plates. The product appears to be identical with the
"dinitrodibenzyl disulphonic acid" obtained by Bender (Berichte of the German
Chemical Society, 28, 423) as a bye product in the preparation of curcumine. The
free acid is easily soluble in water. The sodium salt is sparingly soluble in presence
of caustic soda. The ammonium salt is also somewhat sparingly soluble.
aniline and phenyl hydrazine salts are nearly insoluble white precipitates.
Example No 2. 100 lbs. of sodium paranitrotoluene sulphonate are dissolved in
200 gallons of warm water. 20 gallons of caustic soda lye of 30% Na OH and 50 gallons
of sodium hypochlorite solution containing 7% available chlorine are added. The
solution is kept at about 40° Centigrade until the hypochlorite has entirely disappeared.
On cooling the sodium dinitrodiphenylethylene disulphonate crystallises out in nearly
colourless flat needles, which are filtered off and dried. The free acid is obtained by
dissolving the sodium salt in dilute hydrochloric acid and adding to the hot solution
strong hydrochloric acid in excess. On cooling the sulphonic acid crystallises out in
needles. The alkaline salts like those of dinitrodiphenylethane disulphonic acid are
somewhat sparingly soluble and the aniline and phenylhydrazine salts form very
sparingly soluble precipitates. As both the acid and its salts are colourless it cannot
be identical with the so called "dinitrostilbenedisulphonic acid" described by
Fischer and Heff (Berichte 26, 2234) which is a yellow colouring matter.
Example No. 3. 100 lbs. of dinitrodiphenylethane disulphonic acid or its sodium
salt, are dissolved in 100 gallons of hot water and reduced by addition of 50 gallons of
hydrochloric acid and 200 lbs of iron borings. When the reduction is complete the
product is filtered off, dissolved in aqueous sodium carbonate and filtered from
unaltered iron. From the filtrate the diamidodiphenylethane disulphonic acid is
precipitated by addition of a mineral acid.
Example No. 4.
100 lbs. of dinitrodiphenylethylene disulphonic acid are dissolved
in 100 gallons of boiling water with addition of 50 gallons of hydrochloric acid. To
the boiling solution is slowly added 150 lbs. of zinc dust. When the reduction is

page_text: complete the precipitate is filtered off, extracted with sodium carbonate, filtered from
undissolved zinc and the diamidodiphenylethylene disulphonic acid is precipitated
from the filtrate by addition of an acid.
"The Manufacture and Production of Derivatives of Diphenylethane
and of Diphenylethylene.”.
We, ARTHUR GEORGE GREEN, F.I.C., F.C.S., of 13 Kings Drive, Heaton Moore
near Stockport, and ANDRÉ RAOUL WAHL, of 331 Ashton New Road, Clayton near
Manchester, Consulting Chemists, and THE CLAYTON ANILINE COMPANY LIMITED, or
Clayton aforesaid, 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 :-
We have discovered that by oxidation of paranitrotoluene sulphonic acid in alkaline
solution, two molecules undergo condensation with production of dinitrodiphenylethane
disulphonic acid,
These two products are obtained either in admixture with each other, or separately,
according to the quantity of the oxidising agent employed and the conditions under
which the reaction is performed. In general dinitrodiphenylethane disulphonic acid
is the chief, or sole, product when a quantity of oxidising agent is employed equal to
one atom of oxygen for every two molecules of paranitrotoluene sulphonic acid. On
the other hand dinitrodiphenylethylene disulphonic acid is the chief, or sole, product
when the oxidising agent is employed in quantity equivalent to two atoms of oxygen
for two molecules of paranitrotoluene sulphonic acid. For the production of the
former compound it is, moreover, advantageous to use a large excess of caustic alkali
in order that the product, which is sparingly soluble in the alkali, may be precipitated,
and so protected from further change. For the production of the latter compound
on the other hand a smaller quantity of caustic alkali is desirable. In place of
paranitrotoluene sulphonic acid there may be employed with like effect the unstable
safranine-red compound which is formed from the latter by the gentle action of caustic
alkalies. This red substance which cannot be isolated on account of the ease with
which it changes into sun yellow, or curcumine, appears to be the alkaline salt of a
colourless nitrolic acid, the lead salt of which has a bright blue colour. The
dinitrodiphenylethylene disulphonic acid can also be obtained by oxidation of
dinitrodiphenylethane disulphonic acid whether the latter has been prepared in the
manner already described, or by any other method. Inversely the dinitrodiphenyl-
ethylene disulphonic acid can be converted into dinitrodiphenylethane disulphonic
acid by submitting it to reduction in alkaline solution when it is converted into the
safranine-red body already mentioned which by oxidation gives dinitrodiphenylethane
disulphonic acid.

page_text: For the above mentioned reactions any suitable oxidizing agent capable of acting
in alkaline solution may be employed, such as sodium hypochlorite, sodium peroxide,
lead peroxide, ammonium persulphate, and the like; but we have found that the
most suitable for the purpose is sodium hypochlorite. The oxidation may also be
brought about by submitting paranitrotoluene sulphonic acid to electrolysis at the
anode pole in alkaline solution.
By reduction in acid solution dinitrodiphenylethane disulphonic acid is converted
into diamidodiphenylethane disulphonic acid
NH,.C Hg(SO,H).CH,.CH,.C Hg(SO,H).NH,
0 The reduction of the dinitro compounds to the diamido compounds can be
accomplished by any of the usual acid reducing agents, such as stannous chloride,
zinc dust, iron, and the like.
Both the nitro compounds and the corresponding amido compounds are employed
as intermediate bodies in the manufacture of colouring matters.
The following examples are given to illustrate the general method of carrying out
our invention into practice; but we do not limit ourselves to the precise details.
Example No. 1. 100 lbs of sodium paranitrotoluene sulphonate are dissolved in
100 gallons of warm water. 50 gallons of caustic soda lye, of 30 per cent. NaOH,
are added and, whilst the temperature is kept at about 40°-50° centigrade,
22 gallons of sodium hypochlorite solution containing 7 per cent. of available
chlorine are slowly run in. When all the hypochlorite has disappeared 200 gallons
of cold water are added and the sparingly soluble sodium salt of dinitrodiphenyl-
ethane disulphonic acid is filtered off. It is purified by dissolving in dilute hydro-
chloric acid and adding strong hydrochloric acid to the hot solution, when, on cooling,
the free sulphonic acid crystallises out in large colourless micaceous plates. The
product appears to be identical with the "dinitrodibenzyl disulphonic acid " obtained
by Bender (Berichte of the German Chemical Society 28, 423) as a bye product in
the preparation of curcumine. The free acid is easily soluble in water. The sodium
salt is sparingly soluble in the presence of caustic soda. The ammonium salt is also
somewhat sparingly soluble. The aniline and phenylhydrazine salts are nearly
insoluble white precipitates.
Example No. 2. 100 lbs of sodium paranitrotoluene sulphonate are dissolved in
200 gallons of warm water. 200 gallons of caustic soda lye, of 30 per cent. NaOH,
and 50 gallons of sodium hypochlorite solution containing 7 per cent. available chlorine
are added. The solution is kept at about 400 centigrade until the hypochlorite
has entirely disappeared. On cooling the sodium dinitrodiphenylethylene disul-
phonate crystallises out in nearly colourless flat needles which are filtered off and
dried. The free acid is obtained by dissolving the sodium salt in dilute hydrochloric
acid and adding to the hot solution strong hydrochloric acid in excess.
On cooling
the sulphonic acid crystallises out in needles. The alkaline salts, like those of
dinitrodiphenylethane disulphonic acid, are somewhat sparingly soluble, and the
aniline and phenylhydrazine salts form very sparingly soluble precipitates. As both
the acid and its salts are' colourless it cannot be identical with the so-called
"dinitrostilbenedisulphonic acid" described by Fischer and Hepp (Berichte 26,
2234) which is a yellow-colouring matter.
Example No. 3. 100 lbs of dinitrodiphenylethylene disulphonic acid are dissolved
in 100 gallons of boiling water with the addition of 50 gallons of hydrochloric acid.
To the boiling solution is slowly added 150 lbs of zinc dust. When the reduction is
complete the precipitate is filtered off, extracted with sodium carbonate, filtered from

page_text: undissolved zinc and the diamidodiphenylethylene disulphonic acid is precipitated
from the filtrate by the addition of an acid.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The manufacture and production of dinitrodiphenylethane disulphonic acid by
alkaline oxidation of paranitrotoluene sulphonic acid, or of the red unstable trans-
formation product of the latter by caustic alkali, substantially as hereinbefore
described.
2. The manufacture and production of dinitrodiphenylethylene disulphonic acid by
alkaline oxidation of paranitrotoluene sulphonic acid, or of the red unstable trans-
formation product of the latter by caustic alkali, substantially as hereinbefore
described.
3. The manufacture and production of dinitrodiphenylethylene disulphonic acid by
alkaline oxidation of dinitrodiphenylethane disulphonic acid substantially as herein-
before described.
4. The method of carrying out the processes claimed under the foregoing first
second and third claiming clauses by the employment of sodium hypochlorite as
oxidising agent as described in the foregoing Examples 1 and 2.
5. The manufacture and production of diamidodiphenylethylene disulphonic acid
by the reduction of dinitrodiphenylethylene disulphonic acid in acid solution.
6. As a new product the dinitrodiphenylethylene disulphonic acid such as is
obtained by the processes claimed under the foregoing second third and fourth
claiming clauses.
0
Th: 00-11 Nawambor 1907
JOHNSONS & WILLCOX
47 Lincoln's Inn Fields, London, W.C., Agents.