DE663995C - Process for the preparation of substituted 3-aminopyrene - Google Patents

Description

Process for making substituted 3-aminopyrenes During disubstitution des Pyrene, as found in a large number of cases examined was, always mixtures of pyrene-3, 8- with the corresponding pyrene-3, io-diderivaten. The type of substituents (whether e.g. halogen, S 03H, NO2, ketone or Alkyl radical) shows no significant differences. Even if a second any substituent introduced into a pyrene monosubstituted in the 3-position is predominantly mixtures of the corresponding 3, 8- and 3, io-pyrene derivatives, so z. B. in the nitration of 3-acetaminopyrene or in the halogenation of 3-nitropyrene. The formation of 3-aminopyrene-d-sulfonic acid described in patent specification 615,528 when baking 3-aminopyrene sulfate is the only previously known exception to this rule.

The separation of the mixtures of disubstituted pyrenes obtainable by the above-mentioned methods is in most cases very lossy, since the differences in solubility of the isomers are only very small and make repeated fractional crystallization necessary. The dinitropyrene obtainable with very good yield in the dinitration of pyrene z. B. has already been described by various editors (Graben, A. 158, 292-g3; E. Goldschmiedt, M2, 58o and jahota, M.8, 449), without its inconsistency having been noticed at all. By boiling the crude dinitropyrene several times with pyridine and repeated fractional crystallization of the residue, it was possible to separate pure 3, 8-dinitropyrene (long, shiny, pale yellow needles from nitrobenzene, melting point 309 °) from the mixture in moderate yield, while the g, io isomers could not be isolated in pure form.

It has now been found that the separation of isomeric 3, 8- and 3, io-pyrene derivatives is relatively easy if at least one of the two substituents is an amino group, according to the following formulation: wherein R is a substituent. The differences in solubility that exist in these aminopyrenes are considerably greater than in the case of the corresponding nitropyrenes, so that the separation: the isomer @ n z. B. either with organic solvents $ @; medium or, since the salts of this Am show strong differences in solubility, strong aqueous acids can often be achieved in a single operation.

The uniform aminopyrenes obtainable by the present process are of interest as intermediates in the manufacture of dyes.

Examples 1. 77 parts by weight of dinitropyrene from a temperature of 28o to 29o ° (mixture of 3, 8- and 3, lo-dinitropyrene, obtainable by nitrating pyrene in glacial acetic acid with z moles of nitric acid, i.e. 1.5, or from very finely divided 3 -Nitropyrene in water with nitric acid at 7 o to 8o °) are treated in 550 parts by weight of alcohol with 2 ° 1o nickel catalyst at 70 ° in a stirred autoclave with hydrogen until the pressure no longer decreases. After it has cooled, it is filtered off with suction, the residue is boiled with xylene and the nickel catalyst is filtered off. The 3,8-diaminopyrene separates out of the filtrate in a relatively pure form. After repeated crystallization from xylene or trichlorobenzene, the 3, 8-diaminopyrene is pure. It has a constant melting point of 232 to 233 °, is colorless in concentrated sulfuric acid and has a strong violet fluorescence. The alcoholic filtrate is concentrated and the residue is recrystallized from toluene or xylene. The 3, io-diaminopyrene precipitates in large prisms that melt constantly at 162 °. Larger crystals show dark olive color in both isomers, while the color is ne-yellow on trituration.

2. 29.2 parts by weight of dinitropyrene from F. 28o to s 290 ° are in Suspended 25o parts by weight of alcohol and a solution of 57 parts by weight Sodium sulfhydrate (3%) and 6o parts by weight of water are added. After about The same amount of sodium sulfhydrate is added again for an hour and a half and the mixture is boiled until the purple solution has turned yellow. After cooling down is suctioned off, washed with water and dried. Yield: 18 parts by weight Crude diamino-pyrene with a temperature of 160 °.

18 parts by weight of this diaminopyrene are 36o parts by weight 2% sulfuric acid and 96 parts by weight of water briefly boiled. Here the sulfate of 3, 8-diaminopyrene separates in light gray needles. It will suctioned hot and the sulfate made alkaline with ammonia, with cleavage of the Sulfates occurs. The free amine is filtered off with suction and dried. From.,> ": Ylol recrystallized, it shows a melting point of 23o to 232 ° and is pure '; 8-diaminopyrene.

The sulfate of 3, io-diaminopyrene separates from the filtrate on cooling the end; after making it alkaline with ammonia, the free 3, io-diaminopyrene is obtained, which after recrystallization shows a melting point of 154 ° and is almost pure is.

3. 6o parts by weight of nitroacetaminophenes at a temperature of 25q. ° (mixture of 3, 8- and 3, io-derivative, obtained by nitrating 3-acetaminopyrene with i mol Nitric acid in glacial acetic acid) in 300 parts by weight of alcohol with the addition of 3 ° j, nickel catalyst treated with hydrogen at 65 to 70 ° in a stirred autoclave, until the pressure remains constant. After cooling, it is suctioned off and the residue dissolved in 66o parts by weight of pyridine, filtered and the solution with 300 parts by weight Water diluted; after 2 to 3 hours, the 3, 8-aminoacetäminopyrene separates from, which after recrystallization from a nitrobenzene-chlorobenzene mixture i: i the melting point of 28o °. The aqueous pyridine filtrate is mixed with a further 2000 parts of water diluted. Here the 3-acetamino-io-aminopyrene (F.246 °) separates out. By Boiling these aminoacetaminopyrene with dilute hydrochloric acid saponifies them, and the di: aminopyrene is obtained in its pure form.

One can also proceed in such a way that one uses the mixture of nitroacetaminopyrene saponified with dilute hydrochloric acid, the mixture of nitroaminopyrene is catalytic reduced and then, as indicated above, fractionated the free diamines.

4. 42 parts by weight of chloronitropyrene with a temperature of i52 ° (mixture of 3, 8- and 3, io derivative, prepared by nitrating 3-chloropyrene in glacial acetic acid with i mole of nitric acid, d. 1.5) parts by weight of alcohol are used in Zoo with the addition of 2 ° 1o nickel catalyst treated with hydrogen at 6o to 70 ° in a stirred autoclave, until the pressure remains constant. After cooling, the whole reaction mass, in which the reduction product is partly in excreted form, heated, so much alcohol is still added that essentially only the catalyst Remains undissolved in your hot alcohol. From the hot filtered alcoholic solution On cooling, an aminochloropyrene crystallizes in long yellow needles, which after repeated recrystallization at 1q.2 ° melts constantly and the 3, 8-cliloraininopyrene represents. The 3, io-chloram, itiopyrene crystallizes from the alcoholic filtrates after standing for a long time in yellow leaflets with a temperature of 18 °.

5. 11 5 parts by weight of nitroacetyl pyrene (mixture of 3, 8 and 3, 1o derivatives. Obtained from 3-acetyl pyrene by nitration in glacial acetic acid with 1 mol of nitric acid, i.e. 1.5) are as in Example q. Catalytically reduced in alcohol.

The mixture of 3, 8- and 3, Io-aminoacetyl pyrene thus obtained is separated by recrystallization from alcohol, in which the 3, 8-derivative .schwerer is soluble. It crystallizes from chlorobenzene in orange-yellow prisms with a temperature of 1g2 °, while the more soluble 3, Io-Aminoacetylpren in orange-yellow skewers from Crystallized at 136 °.

6. 24th, 6 parts by weight of pyrene-3-carboxylic acid «earths, finely ground and suspended in 750 parts by weight of nitrobenzene. A mixture of 7.5 parts by weight of nitric acid (1.5) and 50 parts by weight of nitrobenzene is allowed to flow in at 75 ° and the mixture is heated to 170 ° to 180 °, the suspension going completely into solution. On cooling, a mixture of probably 3, 8- and 3, io-nitropyrenecarboxylic acid with a temperature of 27o to 285 ° crystallized in yellow needles is obtained. Concentrated sulfuric acid dissolves with olive-green, diluted sodium hydroxide solution with a yellow-red color.

By catalytic hydrogenation of the aqueous Na salt solution of the two Nitropyrene carboxylic acids with nickel give a light yellow fluorescent solution of the corresponding aminopyrene carboxylic acids, which are obtained by acidification with dilute hydrochloric acid deposited as salts in the form of thick, red-brown flakes. When boiling In this suspension, one isomer with a light yellow color goes into solution and separates turns yellowish after filtration from the residue containing the other isomer thick, mucus. i, g off again. With careful addition of diluted alkali it is preserved yellow-brown flakes of the free 3-aminopyrene-Io-carboxylic acid, soluble in concentrated Sulfuric acid of greenish yellow color and vivid green fluorescence, in dilute Sodium hydroxide solution pale yellow with gray-green fluorescence.

The red-brown hydrochloric acid filter residue is suspended in water and neutralized with dilute sodium hydroxide solution. The isomeric 3-aminopyrene-8-carboxylic acid is obtained in brown flakes, soluble in concentrated sulfuric acid with yellow blue-green fluorescence, in dilute sodium hydroxide solution yellow with gray-green fluorescence.

Claims (1)

PATRNTANSPRUCI3: Process for the preparation of substituted 3-aminopyrenes, characterized in that mixtures of fully isomeric pyrenes of the following constitution are used: in which R denotes a substituent, separates into the two isolators due to the different solubility of the two isomers.