Aniline Yellow
- E-4 -aminoazobenzene
- E-1 -amino-4 - phenylazobenzol
- E-4 - phenylazoaniline
- E-4 - Phenyldiazenylanilin (IUPAC)
- E -p- Aminodiphenylimid
- E -p- phenylazoaniline
- E -p- Phenylazophenylamin
- E- AAB
- C. I. 11000
- C. I. Solvent Blue 7
- C. I. Solvent Yellow 1
- Fat Yellow AAB
- Oil Yellow AAB
- Solvent Yellow 1
- Sudan Yellow R
- EINECS 200-453-6
Yellow leaves or needles
Fixed
1.19 g · cm -3
127 ° C.
> 360 ° C
0.4 Pa ( 90 ° C)
- Soluble in benzene, chloroform and ethanol
- Practically insoluble in water
Risk
200 mg · kg -1 ( LD50, mouse, ip)
Template: Infobox chemical / molecular formula search available
Aniline yellow ( p- aminoazobenzene ) is a yellow azo dye. It is a derivative of azobenzene while an aromatic amine.
Properties
Aniline yellow crystallized in yellow needles or leaflets, amorphous aniline yellow is an orange powder, which is highly carcinogenic and beyond is suspected to be mutagenic.
History
Aniline Yellow was the first synthetic azo dye.
1860 described the German chemist Peter Griess the synthesis of a crystallising in golden yellow plates explosive substance, which he had obtained by the action of nitrous acid on an alcoholic aniline solution before described in the following year C. Mene and Hugo ship which yield a yellow dye, which they in first case had recovered by the action of nitrous acid on aniline, while in the latter by the action of sodium stannate and sodium antimonate as oxidants on aniline.
Simpson, Maule and Nicholson, 1864 as the second azo dye ( discovered after 1863 and in the same year on the market separately aniline black ) this dye introduced into the trade, starting that the aniline yellow produced by the method of C. Mene participated in the process of and the substance described by Griess were identical. The reasons why they ignored the explosive properties of the latter completely, is unknown.
The discrepancy gave rise to further investigations by Griess himself and Carl Alexander von Martius, which showed that the " diazoamidobenzene " 1860 manufactured by Griess in boiling hydrochloric acid under nitrogen elimination decomposed into phenol and aniline, while in an oxalate of " Amidodiphenylimids " trade located aniline yellow than decomposition products under the same conditions neither nitrogen nor development phenol and aniline. Was added, that the aniline yellow produced by the method of Mene significantly basic reacted while Griess ' " diazoamidobenzene " put little basic behavior on the day.
Since the ring structure of benzene at this time was still largely unknown, they could make no further statements on the exact structure of the two compounds, but recognized by their same elemental composition after all, already its isomeric nature and the fact that both belong to the same class as discovered by Mitscherlich azobenzene found.
The most important result of these studies, however, was the finding that the formation of one or the other product was dependent on the temperature: While in the cold, the formation of the explosive " Diazoamidobenzols " prevailed, led the application of heat to form the " Amidodiphenylimids " or aniline yellow.
From today's perspective, one can interpret the results as follows:
After the aniline is diazotized as is well known (see diazotization ), the resulting diazonium cation in the heat with another aniline molecule to the thermodynamically more stable p- aminoazobenzene responding ( IUPAC: 4 - [( E)- Phenyldiazenyl ] aniline, thermodynamic control ), at low temperature on the other hand with the nitrogen atom of the amino group of the aniline as its nukleophilster point to form a triazene (IUPAC: (1E ) -1,3- Diphenyltriaz -1-ene, kinetic product control). Failure to recognize such Triazenbildungen instead of azo coupling often leads still to accidents.
Production and representation
Aniline yellow can be obtained by the action of nitrous acid on aniline and. By acid rearrangement of 1,3- Diphenyltriazen
Use
Aniline yellow (also inkjet printers ) used as a staining agent in microscopy, in pyrotechnics for generating yellow smoke, as a yellow pigment in the ink. Furthermore finds / it was used as an insecticide, as a staining agent for paints, waxes and plastics. Aniline Yellow is also a starting material for other dyes.
Proof
Methods of analysis:
Aniline Yellow is defined as carcinogenic amine in the list of aromatic amines, for statutory limits in the EU, included ( 2008: 30 ppm). The import and distribution of commodities that exceed the specified limits, is prohibited in the EU. The implementation in national law is via the Commodities Regulation. The determination is made by the analytical method in the official compendium of test methods § 35 of the LMBG under the section number B- 82.02.
Short Description: reduction of the sample with dithionite extraction of aromatic amines with MTBE and chromatographic assay of the amines ( TLC, HPLC-DAD/MSD ).