The Manufacture or Production of Paranitrobenzaldehyde-ortho- sulphonic Acid and Colouring Matters therefrom
Year: 1897

page_text: Date of Application, 23rd Sept., 1897
Complete Specification Left, 19th July, 1898-Accepted, 20th Aug., 1898
The Manufacture or Production of Paranitrobenzaldehyde-ortho-
sulphonic Acid and Colouring Matters therefrom.
We, ARTHUR GEORGE GREEN, F.I.C., F.C.S., of 13, King's Drive, Heaton Moor,
Stockport, and ANDRÉ RAOUL WAHL, of 331, Ashton New Road, Clayton, near
Manchester, and THE CLAYTON ANILINE COMPANY LIMITED, of Clayton aforesaid, all
in the County of Lancaster, do hereby declare the nature of this invention to be as
follows:-
Paranitrotoluene sulphonic acid when treated with alkaline oxidising agents is con-
verted successively into dinitrodiphenylethane disulphonic acid-
•
[4:21] (NO2) (SOH) CH, CH₂ · CH₂ CH₂ (SO₂H) (NO₂) [1: 2: 4]
CH CH, (SO,H) (NO₂) [1:2:4]
The paranitrobenzaldehyde orthosulphonic acid forms an important starting point
for the preparation of colouring matters of the triphenylmethane and pyrone groups,
which in general with other colouring-matters containing a sulphonic residue (HSO₂)
in the ortho position to the central methane carbon, possess great stability against
the action of alkalies, whilst, in other respects also, they are valuable dyes.
preparation of paranitrobenzaldehyde orthosulphonic acid is illustrated by the follow-
ing example:-
The
20 lbs. of dinitrodiphenylethylene disulphonate of soda are dissolved in 25 gallons
of water and the solution is cooled to about 10° Centigrade and into it whilst agitated
energetically is slowly run 8 lbs. of potassium permanganate dissolved in 15 gallons
of water. The mixture is then gently warmed and filtered from the precipitated
oxide of manganese. The filtrate is neutralised with hydrochloric acid and con-
centrated until on cooling the sodium salt of paranitrobenzaldehyde orthosulphonic
acid crystallises out in small white crystals which are very soluble in water, but
insoluble in alcohol. In aqueous solution it gives, with aniline, a yellow precipitate;
with phenylhydrazine, an orange-red precipitate; and with paraphenylene diamine, a
brownish-orange precipitate.
In place of the potassium permanganate of the above example, other oxidising
agents may be used and since the dinitrodiphenylethylene disulphonic acid is itself

page_text: formed by oxidation of paranitrotoluene sulphonic acid it follows that by employ-
ment of a suitable oxidising agent the series of reactions may be combined into one
operation and the aldehyde obtained direct from paranitrotoluene sulphonic
acid.
The paranitrobenzaldehyde orthosulphonic acid condenses readily with secondary
and tertiary amines of the benzene and naphthalene series, with the production of
leuco compounds of blue and green colouring-matters of the triphenylmethane
group. It also condenses with the alkylated metamidophenols and metamidocresols
giving rise to dioxyalkyldiamidonitrotriphenyl methane sulphonic acids which, by
treatment with dehydrating agents, such as concentrated sulphuric acid, are converted
into alkyldiamidonitrotriphenylmethane oxide sulphonic acids, which latter are leuco
compounds of red-colouring-matters analogous to the rhodamines. These condensa-
tions are effected by boiling together the constituents in slightly acid aqueous
solution or by heating them together in the presence of condensing agents such as
sulphuric acid, zinc chloride, or the like. The conversion of the leuco compounds
into the corresponding colouring-matters can be effected by oxidation with lead
peroxide, ferric chloride, potassium bichromate, and the like.
The general method of preparation of these colouring-matters is illustrated by the
following example :—
25 lbs. of paranitrobenzaldehyde orthosulphonate of soda is dissolved in 25 gallons
of water with the addition of 1 gallon of hydrochloric acid (33 per cent. HCl), 58 lbs.
of benzylethylaniline sulphonic acid are added and the mixture is boiled for 24 hours.
The solution is then diluted with 200 gallons of water, acidified with 10 lbs. of
sulphuric acid and oxidised cold by the addition of 25 lbs. of peroxide of lead.
sulphate of lead is filtered off and the solution of the colouring-matter after
neutralisation with ammonia is evaporated to dryness. It dyes wool and silk a
blueish-green unaffected by alkalies.
The
1005
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.
The Manufacture or Production of Paranitrobenzaldehyde-ortho-
sulphonic Acid and Colouring Matters therefrom.
We, ARTHUR GEORGE GREEN, F.I.C., F.C.S., of 13, King's Drive, Heaton Moor,
Stockport, and ANDRÉ RAOUL WAHL, of 331, Ashton New Road, Clayton, near
Manchester, and THE CLAYTON, ANILINE COMPANY LIMITED, of Clayton aforesaid, all
in the County of Lancaster, 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:―
In Letters Patent No. 5351 of 1897 we have shewn that para-nitrotoluene sulphonic
acid when treated with alkaline oxidising agents is converted successively into dinitro-
diphenylethane disulphonic acid.
.
[4:21] (NO2) (SO₂H) CH, CH, CH, CH, (SO,H) (NO2) [1:2:4]
and dinitrodiphenylethylene disulphonic acid.
3
.
[421] NO, (SO,H) CH, CH: CH C, H, (SO,H) NO, [1:2:4]

page_text: By submitting the latter body to still further oxidation, paranitrobenzaldehyde
orthosulphonic acid is produced. This reaction is represented by the equation

page_text: EXAMPLE 3.
A solution of 12 lbs of paranitrobenzaldehyde orthosulphonic acid in 17 gallons
of water is mixed with 16 lbs. of metaamidophenol and 8 lbs. of sulphuric acid, and
boiled for several hours. The leuco-compound which separates out is dried. 10 lbs.
of the said leuco compound are dissolved in 40 lbs. of concentrated sulphuric acid and
the mixture is heated for about half-an-hour at a temperature of from 135° to 140°
Centigrade. The oxidation of the leuco compound to the colouring-matter takes place
under these conditions simultaneously with the dehydration. The red sulphuric acid
solution is cooled and poured into 40 gallons of cold water. The colouring-matter in
part separates out the remainder being precipitated by the addition of salt. Filtered
off and dried it forms a red powder, scarcely soluble in cold water but more soluble in
hot water. It dyes silk a bluish. red.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. The manufacture of paranitrobenzaldehyde orthosulphonic acid by oxidizing
dinitrodiphenylethylenedisulphonic acid of Letters Patent 5351 of 1897.
2. The manufacture of paranitrobenzaldehyde ortho-sulphonic acid by oxidising
dinitrodiphenylethylene disulphonic acid of Letters Patent 5351 of 1897 by means
of potassium permanganate at a low temperature.
3. The manufacture of colouring-matters of the triphenylmethane series by the
condensation of paranitrobenzaldehydeorthosulphonic acid with secondary, or tertiary,
amines of the benzene series, or sulphonic acids thereof, and subsequent oxidation.
4. The manufacture of colouring-matters of the pyrone group by the condensation
of paranitrobenzaldehydeorthosulphonic acid with alkylated, or alphylated, meta-
midophenols, or metamidocresols, or sulphonic acids thereof, and subsequent
dehydration and oxidation.
5. As a new product paranitrobenzaldehyde orthosulphonic acid.
6. As new products the colouring-matters such as are obtained by the processes
claimed under the foregoing Claims 3 and 4.
Dated this 19th day of July 1898.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.