Manufacture or Production of Aromatic Aldehydes and of Colouring Matters therefrom.
Year: 1897

page_text: Date of Application, 25th Sept., 1897
Complete Specification Left, 25th June, 1898-Accepted, 24th Sept.,
1898
PROVISIONAL SPECIFICATION.
Manufacture or Production of Aromatic Aldehydes and of Colouring
Matters therefrom.
We, IVAN LEVINSTEIN and LEVINSTEIN LIMITED, of Minshull Street, Man-
chester, in the County of Lancaster, Chemical Manufacturers, do hereby declare
the nature of this invention to be as follows:-
In the Provisional Specification left by us with our application for Letters
Patent No. 19904 dated the 30th August 1897, we have described, that if the
new product therein referred to (which our more recent researches indicate to be
probably a dinitrostilbene sulphonic acid), and which results from the treatment
of para-nitrotoluene sulphonic acid with hypochlorites, is carefully oxidised, a
new compound results which shews all the properties of an aromatic aldehyde.
We have further described, in the Provisional Specification left by us with our
application for Letters Patent No. 21060 dated the 14th September 1897, that
similar (aldehyde) compounds are produced if the products of condensation pre-
pared by heating para-nitrotoluene sulphonic acid with caustic alkalies (as
described in the Specifications of Letters Patent No. 4387 dated the 29th day of
March 1888 and No. 23672 dated the 22nd December 1892), are carefully oxidised,
as for example by potassium permanganate in the cold.
We have now discovered that this reaction is not limited to the above men-
tioned examples but is generally applicable to stilbene derivatives, and that there-
fore aromatic aldehyde compounds may be produced by the oxidisation of the
corresponding stilbene derivatives with suitable oxidising agents, as for example
by means of potassium permanganate in the cold. Thus, for example, if stilbene
ortho-disulphonic acid (which may be easily produced for instance, by replacing
the amido group of the diamidostilbene disulphonic acid by hydrogen in the well
known manner), is oxidised, an aldehyde sulphonic acid is formed. If this aldehyde
compound is condensed with alkylated aromatic amines or with their sulphonic
acids, sulphonic acids of leuco bases result which, when oxidised, give very valu-
able blue-green colouring matters of the triphenylmethane series.
י
Dated this 24th day of September A.D. 1897.
W. E HEYS & SON,
Agents for the Applicants.
Manufacture or Production of Aromatic Aldehydes and of Colouring
Matters therefrom.
We, IVAN LEVINSTEIN, and LEVINSTEIN LIMITED, of Minshull Street, Man-
chester, in the County of Lancaster, Chemical Manufacturers, do hereby declare
DQ71

page_text: 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 the specification left by us with our application for Letters Patent No. 19904
dated the 30th day of August A.D). 1897, we have described that if the new pro-
duct therein referred to (which our more recent researches indicate to be probably
a dinitrostilbene disulphonic acid), and which results from the treatment of para-
nitrotoluene sulphonic acid with hypochlorites, is carefully oxidised, a new com-
pound results which shews all the properties of an aromatic aldehyde. This alde-
hyde has probably the constitution of paranitrobenzaldehyde orthosulphonic acid.
We have now discovered that this reaction is not limited to the above example
but is generally applicable to stilbene derivatives and that therefore aromatic
aldehyde compounds may be produced by the oxidation of the corresponding
stilbene derivatives with suitable oxidising agents, as for example by means of
potassium permanganate in the cold. Thus, for example, orthosulphobenzalde-
hyde may be obtained by carefully oxidising stilbeneorthodisulphonic acid with
potassium permanganate in the cold.
If these aldehyde compounds are condensed with alkylated aromatic amines or
their sulphonic acids, sulphonic acids of leuco bases result which, when oxidised,
give very valuable blue to blueish-green colouring matters of the triphenylme-
thane series..
The following examples are given in illustration of the processes we may employ
in carrying out our invention.
EXAMPLE I.
Production of orthosulphobenzaldehyde from stilbene orthodisulphonic acid.
28.4 kilos. of stilbene orthodisulphonate of sodium (which may be easily produced
as for example by replacing the amido group of diamidostilbene disulphonic acid
by hydrogen in the well known manner), is dissolved in about 800 litres of water
and there is gradually run into it whilst it is being rapidly stirred, a solution of
21.0 kilos. of potassium permanganate in about 500 litres of water. During the
reaction, the temperature is preferably kept at about 5° C., and a current of carbon
dioxide is passed through the liquid: When the oxidation is completed, tho
liquid is boiled up and filtered from the manganese dioxide. It contains the
sodium salt of the orthosulphobenzaldehyde and may be directly used in the pro-
duction of colouring matters. Or, the liquid may be evaporated to dryness and
the sodium salt of the benzaldehyde orthosulphonic acid may be extracted from
the residue by boiling alcohol from which it separates out on cooling as a white
crystalline powder readily soluble in water.
EXAMPLE II.
Production of a pure blue colouring matter by the condensation of orthosulpho-
benzaldehyde with ethylbenzylanilinesulphonic acid.
20.7 kilos. of pure benzaldehyde sodium orthosulphonate obtained as described in
the preceding example, or a corresponding quantity of a less pure sainple, "is dis-
solved in about 200 litres of water weakly acidified with sulphuric acid. 29.5 kilos.
of ethylbenzylaniline sulphonic acid is then added and the whole mixture is
heated to gentle boiling in a reflux apparatus for about 24 hours. When the
formation of the leuco base is completed, the liquid is largely diluted with water
and an excess of sulphuric acid is added. The leuco base is oxidised by gradually
running in the theoretical amount of a paste of lead peroxide prepared from
33.0 kilos. of lead nitrate. When the oxidation is finished, the lead sulphate is
filtered off, the filtrate is made alkaline with ammonia and evaporated to dryness.
The colouring matter thus obtained dyes animal fibres in an acid bath a beautiful
pure blue colour which is distinguished by its brightness and fastness to alkalies.
We desire it to be distinctly understood that we do not limit ourselves to the
above given examples as they are merely types of applicable processes.

page_text: Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
1. The herein before described process for the production of aldehyde compounds
of the benzene series which consists in oxidising stilbene derivatives with suit-
able oxidising agents, and preferably with potassium permanganate in the cold,
substantially as set forth.
2. The process for the production of benzaldehydeorthosulphonic acid by the
oxidation of stilbeneorthodisulphonic acid, substantially as set forth.
3. The process for the production of triphenylmethane colouring matter which.
consists in condensing the aldehyde compounds prepared as set forth in the first
preceding claim, with alkylated aromatic amines or their sulphonic acids to leuco
bases and in oxidising these leuco bases to colouring matters, substantially as
described.
1.
3
1000