4-Nitrochlorobenzene
![]() | |
Names | |
---|---|
IUPAC name
1-Chloro-4-nitrobenzene
| |
Other names
4-Chloro-1-nitrobenzene; 4-Chloronitrobenzene; p-Nitrochlorobenzene; PNCBO
| |
Identifiers | |
3D model (JSmol)
|
|
ChemSpider | |
ECHA InfoCard | 100.002.554 |
KEGG | |
CompTox Dashboard (EPA)
|
|
| |
| |
Properties | |
C6H4ClNO2 | |
Molar mass | 157.55 g·mol−1 |
Appearance | Light yellow solid |
Density | 1.52 g/cm³ (20 °C) |
Melting point | 83.6 °C (182.5 °F; 356.8 K) |
Boiling point | 242.0 °C (467.6 °F; 515.1 K) |
Insoluble | |
Solubility in other solvents | Soluble in toluene, ether, acetone, hot ethanol |
Hazards | |
Flash point | 12 °C (54 °F; 285 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
4-Nitrochlorobenzene is the organic compound with the formula ClC6H4NO2. It is a pale yellow solid. 4-Nitrochlorobenzene is a common intermediate in the production of a number of industrially useful compounds, including common antioxidants found in rubber. Other isomers with the formula ClC6H4NO2 include 2-nitrochlorobenzene and 3-nitrochlorobenzene.
Preparation
4-Nitrochlorobenzene is prepared industrially by nitration of chlorobenzene:[1]
- ClC6H5 + HNO3 → ClC6H4NO2 + H2O
This reaction affords both the 2- and the 4-nitro derivatives, in about a 1:2 ratio. These isomers are separated by distillation. 4-Nitrochlorobenzene was originally prepared by the nitration of 4-bromochlorobenzene by Holleman and coworkers.[2]
Applications
4-Nitrochlorobenzene is an intermediate in the preparation of a variety of derivatives. Nitration gives 2,4-dinitrochlorobenzene, and 3,4-dichloronitrobenzene. Reduction with iron metal gives 4-chloroaniline. The electron-withdrawing nature of the appended nitro-group makes the benzene ring especially susceptible to nucleophilic aromatic substitution, unlike related chlorobenzene. Thus, the strong nucleophiles hydroxide, methoxide, and amide displace chloride to give respectively 4-nitrophenol, 4-nitroanisole, 4-nitroaniline. [1]
Another major use of 4-nitrochlorobenzene is its condensation with aniline to produce 4-nitrodiphenylamine. Reductive alkylation of the nitro group affords secondary aryl amines, which are useful antioxidants for rubber.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/c2/Dapsone.svg/230px-Dapsone.svg.png)
Safety
The National Institute for Occupational Safety and Health considers 4-nitrochlorobenzene as a potential occupational carcinogen that may be absorbed through the skin.[3] The Occupational Safety and Health Administration set a permissible exposure limit of 1 mg/m3, while the American Conference of Governmental Industrial Hygienists recommends an airborne exposure limit of 0.64 mg/m3, over a time-weighted average of eight hours.[4][5]
References
- ^ a b c Gerald Booth "Nitro Compounds, Aromatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH: Weinheim, 2005. doi:10.1002/14356007.a17_411
- ^ "The nitration of mixed dihalogen benzenes" Recueil des Travaux Chimiques des Pays-Bas et de la Belgique. Amsterdam, 1915; pp. 204-235.
- ^ CDC - Immediately Dangerous to Life or Health Concentrations (IDLH): p-nitrochlorobenzene
- ^ CDC - NIOSH Pocket Guide to Chemical Hazards
- ^ New Jersey Department of Health and Senior Services - Hazardous Substance Fact Sheet