2-Nitroaniline
| |||
Names | |||
---|---|---|---|
Preferred IUPAC name
2-Nitroaniline | |||
Systematic IUPAC name
2-Nitrobenzenamine | |||
Other names
ortho-Nitroaniline
o-Nitroaniline | |||
Identifiers | |||
3D model (JSmol)
|
|||
ChEMBL | |||
ChemSpider | |||
ECHA InfoCard | 100.001.687 | ||
EC Number |
| ||
PubChem CID
|
|||
RTECS number |
| ||
UNII | |||
UN number | 1661 | ||
CompTox Dashboard (EPA)
|
|||
| |||
| |||
Properties | |||
C6H6N2O2 | |||
Molar mass | 138.126 g·mol−1 | ||
Appearance | Orange solid | ||
Density | 1.442 g/mol | ||
Melting point | 71.5 °C (160.7 °F; 344.6 K) | ||
Boiling point | 284 °C (543 °F; 557 K) | ||
0.117 g/100 ml (20°C) (SIDS) | |||
Acidity (pKa) | -0.3 (of anilinium salt) | ||
-66.47·10−6 cm3/mol | |||
Hazards | |||
GHS labelling: | |||
![]() ![]() | |||
Danger | |||
H301, H311, H331, H373, H412 | |||
P260, P261, P264, P270, P271, P273, P280, P301+P310, P302+P352, P304+P340, P311, P312, P314, P321, P322, P330, P361, P363, P403+P233, P405, P501 | |||
Flash point | 168 °C (334 °F; 441 K) | ||
Related compounds | |||
Related compounds
|
3-Nitroaniline, 4-Nitroaniline | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
2-Nitroaniline is an organic compound with the formula H2NC6H4NO2. It is a derivative of aniline, carrying a nitro functional group in position 2.[1] It is mainly used as a precursor to o-phenylenediamine.
Synthesis
[edit]2-Nitroaniline is prepared commercially by the reaction of 2-nitrochlorobenzene with ammonia:[2]
- ClC6H4NO2 + 2 NH3 → H2NC6H4NO2 + NH4Cl
Many other methods exist for the synthesis of this compound. Direct nitration of aniline is inefficient since anilinium is produced instead. Nitration of acetanilide gives only traces of 2-nitro isomer is obtained due to the great steric effect of the amide. Sulfonation is usually used to block the 4 position and increases the effectiveness to 56%.[3][4]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/2-nitroaniline_synthesis.svg/488px-2-nitroaniline_synthesis.svg.png)
Uses and reactions
[edit]2-Nitroaniline is the main precursor to phenylenediamines, which are converted to benzimidazoles, a family of heterocycles that are key components in pharmaceuticals.[2]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/6/6d/O-Nitroanilin_Wasserstoffbr%C3%BCcke.svg/142px-O-Nitroanilin_Wasserstoffbr%C3%BCcke.svg.png)
Aside from its reduction to phenylenediamine, 2-nitroaniline undergoes other reactions anticipated for aromatic amines. It is protonated to give the anilinium salts. Owing to the influence of the nitro substituent, the amine exhibits a basicity nearly 100,000x lower than aniline itself. Diazotization gives diazonium derivative,[5] which is a precursor to some diazo dyes. Acetylation affords 2-nitroacetanilide.
See also
[edit]References
[edit]- ^ "Safety data for o-nitroaniline". Archived from the original on 2009-06-28. Retrieved 2011-01-17.
- ^ a b Gerald Booth (2007). "Nitro Compounds, Aromatic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a17_411. ISBN 978-3527306732.
- ^ T. W. Grahan, Solomons; Craig, B. Fryhle; Scott, A. Snyder (2011). Organic chemistry (11 ed.). John Wiley & Sons. pp. 606–607. ISBN 978-1119077251.
- ^ Louis Ehrenfeld, Milton Puterbaugh (1929). "o-Nitrianiline". Organic Syntheses. 9: 64. doi:10.15227/orgsyn.009.0064.
- ^ G. Wittig; R. W. Hoffmann (1967). "1,2,3-Benzothiadiazole 1,1-Dioxide". Org. Synth. 47: 4. doi:10.15227/orgsyn.047.0004.
External links
[edit]- Analysis of 2-Nitroaniline Archived 2014-08-08 at the Wayback Machine