Manufacture of Dinitro- and Diamido-anthraflavic Acid.
Year: 1899

page_text: Date of Application, 11th Oct., 1899
Complete Specification Left, 28th June, 1900-Accepted, 28th July, 1900
PROVISIONAL SPECIFICATION.
Manufacture of Dinitro- and Diamido-anthraflavic Acid.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention (as communicated to me from abroad by The Farbwerke vormals
Meister Lucius & Brüning, of Hoechst "/Main, in the Empire of Germany,
Chemical Manufacturers) to be as follows:-
According to a communication from Schradinger (Ber. S. 1487) a tetranitro-
derivative readily soluble in hot water may be obtained by the action of nitric
acid upon anthraflavic acid.
My foreign correspondents have made the observation that the said dioxy-
anthraquinone may be transformed by the calculated quantity of molecules of
nitric acid into a product which is a dinitro-derivative and not, as was to be
expected, from former experience a mixture of anthraflavic acid and its tetranitro-
derivative.
EXAMPLE I.
24 kilos of anthraflavic acid are dissolved in 10 times the quantity of fuming
sulphuric acid (oleum) of 20% strength into which are stirred while cooling 20.2
kilos. of saltpetre. Whilst this operation is proceeding, the resulting compound
partly separates in crystals. The reaction is completed by heating the mass to
50° C. and the dinitro-compound is isolated by pouring the mass into ice water
and by washing the filtered product till it is neutralised; by dissolving it in
sodium acetate and precipitating with acid the compound is obtained in a pure
state.
EXAMPLE II.
24 kilos. of anthraflavic acid are dissolved in 800 kilos. of sulphuric acid of 66°
specific gravity; into the solution are slowly run 12.6 kilos. (2 molecules) of nitric
acid as such or in the form of nitration acid. After standing for 12 hours, the
whole is poured into water and the compound being filtered is purified by treating
it with lime-water and separating the lime-salt solution with acids. Dinitro-
anthraflavic acid is easily soluble in soda-lye and sodium carbonate, and acetate,
and in lime, or baryta-water with an orange-red colour. The product is soluble
with difficulty in water, glacial acetic acid and benzene, but is easily soluble in
alcohol, from which it crystallises as yellow needles in stellar groups, having a
melting point above 300° C.
A few hundredth parts of the product are of a substance which is soluble with
some difficulty in alcohol and appears to be an isomeric dinitro-anthraflavic acid.
The reduction of the compound is carried out according to the usual methods.
EXAMPLE.
A 1.
1:11 with andúm corhonote in 10
}

page_text: molecules) of sodium sulphide. The liquid assumes a red tint after heating it
on the water-bath for from to hour, the amido compound thus obtained is
precipitated with an acid and purified by dissolving it with sodium carbonate.
It is soluble in sulphuric acid with a yellow-red, in fuming sulphuric acid (oleum)
of 20% strength with a yellow, in alcohol rather easily with a red colour, and
with more difficulty in glacial acetic acid but it is almost insoluble in benzene.
The diamido-anthraflavic acid, thus obtained, dyes wool in an acid bath or when
previously mordanted, without being fast to fulling; the colour is transformed on
subsequent treatment with bichromate into a valuable red-brown fast to fulling.
Dated this 11th day of October 1899.
ABEL & IMRAY,
Agents for the Applicant.
Manufacture of Dinitro- and Diamido-anthraflavic Acid.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, in the
County of London, Chartered Patent Agent, do hereby declare the nature of this
invention (as communicated to me from abroad by The Farbwerke vormals
Meister Lucius & Brüning, of Hoechst "/Main, in the Empire of Germany,
Chemical Manufacturers) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
According to a communication from Schradinger (Ber. 8. 1847) a tetranitro-
derivative readily soluble in hot water may be obtained by the action of nitric
acid upon anthraflavic acid.
My foreign correspondents have made the observation that the said dioxy-
anthraquinone may be transformed by the calculated molecular proportion of
nitric acid into a product which is a dinitro-derivative and not, as was to be
expected from former experience a mixture of anthraflavic acid and its tetranitro-
derivative.
EXAMPLE I.
24 kilos. of anthraflavic acid áre dissolved in 10 times the quantity of fuming
sulphuric acid (oleum) of 20 per cent. strength into which are stirred while cool-
ing 20.2 kilos. of saltpetre. Whilst this operation is proceeding, the compound
produced partly separates as crystals. The reaction is completed by heating the
mass to 50° C. and the dinitro-compound is isolated by pouring the mass into
ice water and by washing the filtered product till it is free from acid; by
dissolving it in sodium acetate and precipitating with acid the compound is
obtained in a pure state.
EXAMPLE II.
24 kilos. of anthraflavic acid are dissolved in 800 kilos. of sulphuric acid of GGO
Beaumé specific gravity; into the solution are slowly run 12.6 kilos. (2 molecular
proportions) of nitric acid as such or mixed with sulphuric acid. After standing
for 12 hours, the whole is poured into water and the compound being filtered is
purified by treating it with lime-water and precipitating it from the lime-salt
solution with acids. Dinitroanthraflavic acid is easily soluble in soda-lye and
sodium carbonate, and acetate, and in lime or baryta-water with an orange-red
colour.
The product is soluble with difficulty in water, glacial acetic acid and benzene,
but is easily soluble in alcohol, from which it crystallises as yellow needles in
stellate groups, having a melting point above 300° C.

page_text: A small percentage of the product is a substance which is soluble with some
difficulty in alcohol and appears to be an isomeric dinitro-anthraflavic acid.
The reduction of the compound is carried out according to the usual methods.
EXAMPLE.
20 kilos. of dinitroanthraflavic acid are dissolved with sodium carbonate in 10
times the quantity of water and the reduction is carried out with 29.1 kilos. (2
molecular proportions) of sodium sulphate. The liquid assumes a red tint after
it has been heated on the water-bath for from 1 to 1 hour, the amido-compound
thus obtained is precipitated with an acid and purified by dissolving it in sodium
carbonate. It is soluble in sulphuric acid to a yellow-red solution, in fuming
sulphuric acid (oleum) of 20 per cent. strength to a yellow solution, in alcohol
rather easily to a red solution, and with more difficulty in glacial acetic acid;
but it is almost insoluble in benzene. The diamido-anthrafiavic acid, thus
obtained, dyes wool in an acid bath or when previously mordanted, without being
fast to fulling; the colour is transformed on subsequent treatment with bichro-
mate into a valuable red-brown fast to fulling.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. The herein described manufacture of dinitroanthraflavic acid by nitrating
anthraflavic acid with the calculated quantity of nitric acid in sulphuric acid.
2. Dinitroanthraflavic acid manufactured as above set forth.
3. The herein described manufacture of diamidoanthraflavic acid by nitrating
anthraflavic acid with the calculated quantity of nitric acid in sulphuric acid
and reducing the product.
4. Diamidoanthraflavic acid, manufactured as above set forth.