Names | |
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Preferred IUPAC name N-Phenylbenzene-1,4-diamine | |
Other names
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Identifiers | |
CAS Number | |
3D model (JSmol) | |
Beilstein Reference | 908935 |
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.002.684 |
EC Number |
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Gmelin Reference | 241334 |
PubChem CID | |
RTECS number |
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UNII | |
UN number | 1673 |
CompTox Dashboard (EPA) | |
InChI
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SMILES
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Properties | |
Chemical formula | C12H12N2 |
Molar mass | 184.242 g·mol |
Appearance | purple–black or dark purple |
Density | 1.09 g/mL |
Melting point | 75 °C (167 °F; 348 K) |
Boiling point | 354 °C (669 °F; 627 K) |
Hazards | |
GHS labelling: | |
Pictograms | |
Signal word | Warning |
Hazard statements | H302, H317, H319, H410 |
Precautionary statements | P261, P264, P270, P272, P273, P280, P301+P312, P302+P352, P305+P351+P338, P321, P330, P333+P313, P337+P313, P363, P391, P501 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). Infobox references |
4-Aminodiphenylamine is a diphenylamine with an additional amine substituent. This dimer of aniline has various industrial uses, including as a hair dye ingredient, but also has raised concerns about toxicity by skin contact. It is also a starting material for the synthesis of 6PPD, an antiozonant for various rubber products. A colorimetric test for the quantitative analysis of nitrite, at levels below 100 nanograms per milliliter, is based on nitrite-catalyzed coupling of 4-aminodiphenylamine with N,N-dimethylaniline.
Synthesis
The most common route of industrial production is by the metal catalysed reaction of aniline with 4‑nitrochlorobenzene to give 4‑nitrodiphenylamine (Buchwald–Hartwig amination):
Subsequent hydrogenation gives 4-aminodiphenylamine. An alternative is the direct reaction of nitrobenzene with aniline via a nucleophilic aromatic substitution of hydrogen (vicarious nucleophilic substitution). This again requires a reduction step but is a good example of industrial green chemistry as it eliminates the need for organochlorine starting materials and metal catalysts.
References
- Khanna, S. K.; Tewari, Pushpa; Joshi, Anil; Singh, G. B. (1987). "Studies on the skin uptake and efflux kinetics of N-phenyl-p-phenylenediamine: an aromatic amine intermediate". International Journal of Cosmetic Science. 9 (3): 137–147. doi:10.1111/j.1467-2494.1987.tb00470.x. PMID 19456976. S2CID 205555627.
- Engels, Hans-Wilhelm; Weidenhaupt, Herrmann‐Josef; Pieroth, Manfred; Hofmann, Werner; Menting, Karl‐Hans; Mergenhagen, Thomas; Schmoll, Ralf; Uhrlandt, Stefan (2007). "Rubber, 4. Chemicals and Additives". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a23_365.pub2. ISBN 978-3527306732.
- Kadowaki, Ryoichi; Nakano, Shigenori; Kawashima, Takuji (1999). "Sensitive flow injection colorimetry of nitrite by catalytic coupling of N-phenyl-p-phenylenediamine with N,N-dimethylaniline". Talanta. 48 (1): 103–107. doi:10.1016/s0039-9140(98)00227-6. PMID 18967448.
- Bochkarev, V.V.; Soroka, L.S.; Bashkin, J.K. (December 2016). "Resource-efficient technology to produce 4-aminodiphenylamine". Resource-Efficient Technologies. 2 (4): 215–224. doi:10.1016/j.reffit.2016.10.011.
- Stern, Michael K.; Hileman, Fredrick D.; Bashkin, James K. (November 1992). "The direct coupling of aniline and nitrobenzene: a new example of nucleophilic aromatic substitution for hydrogen". Journal of the American Chemical Society. 114 (23): 9237–9238. doi:10.1021/ja00049a095.
- Bashkin, James; Rains, Roger; Stern, Michael (1999). "Taking green chemistry from the laboratory to chemical plant". Green Chemistry. 1 (2): G41. doi:10.1039/GC990G41.