DE128845C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

The representation of the valuable for technology halogen-substituted amidoanthraquinone derivatives that have become halogen-substituted of the nitroanthraquinone derivatives, only performed in two separate operations be, d. H. by first reducing the nitro compound and the amido compound formed was then halogenized afterwards. It has now been shown that the nitroanthraquinone derivatives by the energetic action of hydrobromic acid alone or of hydrogen bromide in the presence of bromine in bromamidoanthraquinone derivatives can be converted by simultaneously reducing the nitro groups and replacing hydrogen atoms occurs through halogen.

This course of the reaction could not be foreseen, as the literature did not determine anything Contains clues as to whether when treating the highly molecular and persistent Nitroanthraquinones with hydrobromic acid have any reaction at all, and if so, what for one, whether z. B. only a reduction or a more complicated implementation to be expected was.

The process generally consists in heating the nitroanthraquinone derivative in question with hydrobromic acid under pressure. In this connection the oxygen of the nitro group evidently reacts with the hydrogen bromide in such a way that bromine is set free, and this then apparently has the same substituting effect as if it reacted directly to the amido derivatives in question under the same conditions. Accordingly, according to example I essentially a dibromoamidoanthraquinone is obtained, according to example II a dibromoamidoanthraquinone sulfonic acid, according to example III a tetrabromo-1 · 8-diamidoanthraquinone. The reaction appears to begin at about 120 ⁰ and runs zweckmäfsig at about 150 ^0th However, even with higher heating, z. B. to 200 ⁰ , apparently mainly the same products; The same is true of the use of a dilute or more concentrated hydrobromic acid.

One can also proceed in such a way that one uses the Hydrobromic acid nor bromine. clogs; Finally, one can also use the nitroanthraquinones with hydrogen bromide supplying agents, e.g. B. with bromine and glacial acetic acid.

We give the following examples to explain our process in more detail:

Example I.

10 weight th. Mononitroanthraquinone with 5 weight th. Glacial acetic acid and 75 weight th. Bromine heated ^{to 150 °} C. in the enclosed tube for 12 hours. The reaction mixture is then poured into water, filtered off and washed.

See table for properties.

Example II.

10 weight th. ß-nitroanthraquinone monosulfonic acid (Claus) are with 45 weight th.

Claims (1)

Heated in a sealed tube for 6 hours at 150 ⁰ C. hydrobromic acid (HBr 48 per cent.). The reaction mixture is then poured into water, and the reaction product is salted out from the orange-red solution, filtered off and washed with sodium chloride solution.
'See table for properties. Example III. 10 weight th. 1 · 8-Dinitroanthraquinone are with 9 weight th. Glacial acetic acid and 75 weight th. Bromine heated ^{to 150 °} C. in the enclosed tube for 12 hours. The reaction product is deposited in the manner indicated in Example I. See table for properties. Dibrommonoamidoan-
thrachinon according to Bei
game I. Dibrommonoamidoan-
thraquinone sulfonic acid
according to example II Tetrabromo-1: 8-diamido-
anthraquinone according to Bei
game III Appearance brownish red powder brick-red powder dark red powder Solution in water insoluble orange insoluble Solution in concentrated
sulfuric acid brownish yellow light yellow brownish yellow Solution in sulfuric acid
66 ⁰ B. + boric acid cold orange-red orange red-brown Solution in sulfuric acid
66 ⁰ B. + boric acid to approx.
ioo ° warmed cherry red with weak
Fluorescence cherry red with splendid,
saffron-red fluorescence violet without fluorescence Solution in alcohol orange wine yellow orange Solution in glacial acetic acid orange wine yellow orange Solution in xylene orange-red insoluble orange Solution in nitrobenzene orange-red very little soluble, orange orange-red Solution in aniline cold orange-red almost completely insoluble orange-red Solution in aniline at
Heat Brown brownish red violet red Solution in aniline blue-violet violet red blue. The procedure described does not apply to the nitroanthraquinones given in these examples limited. Instead of these, their isomers or other nitro derivatives of anthraquinone can be used with similar success be used; the other reaction conditions (temperature, concentration etc.) vary within wide limits. Pa τ ε ν τ - A ν s ρ ε υ c η: Process for the direct conversion of nitroanthraquinone derivatives into bromamidoanthraquinone derivatives, consisting in that the nitroanthraquinone derivatives with hydrobromic acid, heated with or without the addition of bromine, or with agents which supply hydrogen bromide.