In dye chemistry.
UN1578 Chloronitrobenzenes, solid or liquid,
Hazard Class: 6.1; Labels: 6.1-Poisonous materials.
p-Nitrochlorobenzene is a yellow crystalline
solid with a sweet odor.
Biological. Under aerobic conditions, the yeast Rhodosporidium sp. metabolized pchloronitrobenzene
to 4-chloroacetanilide and 4-chloro-2-hydroxyacetanilide as final major
metabolites. Intermediate compounds identified include 4-chloronitrosobenzene, 4-chlorophenylhydroxylamine,
and 4-chloroaniline (Corbett and Corbett, 1981).
Under continuous flow conditions involving feeding, aeration, settling, and reflux, a mixture of
p-chloronitrobenzene and 2,4-dinitrochlorobenzene was reduced 61–70% after 8–13 d by
Arthrobacter simplex, a microorganism isolated from industrial waste. A similar experiment was
conducted using two aeration columns. One column contained A. simplex, the other a mixture of
A. simplex and microorganisms isolated from soil (Streptomyces coelicolor, Fusarium sp.,
probably aquaeductum and Trichoderma viride). After 10 d, 89.5–91% of the nitro compounds
was reduced. p-Chloronitrobenzene was reduced to 4-chloroaniline and six unidentified
compounds (Bielaszczyk et al., 1967).
Photolytic. An aqueous solution containing p-chloronitrobenzene and a titanium dioxide
(catalyst) suspension was irradiated with UV light (λ >290 nm). 2-Chloro-5-nitrophenol was the
only compound identified as a minor degradation product. Continued irradiation caused additional
degradation yielding carbon dioxide, water, hydrochloric and nitric acids (Hustert et al., 1987).
Irradiation of p-chloronitrobenzene in air and nitrogen produced 4-chloro-2-nitrophenol and 4-
chlorophenol, respectively (Kanno and Nojima, 1979).
Chemical. Although no products were identified, p-chloronitrobenzene (1.5 x 10-5 M) was
reduced by iron metal (33.3 g/L acid washed 18–20 mesh) in a carbonate buffer (1.5 x 10-2 M) at
pH 5.9 and 15 °C. Based on the pseudo-first-order disappearance rate of 0.0336/min, the half-life
was 20.6 min (Agrawal and Tratnyek, 1996).
A strong oxidizer. Reacts violently with
oxidizers, combustibles, alkalis, sodium methoxide; and
with experimental carcinogenic data. A
poison by ingestion. Experimental
reproductive effects. Mutation data
reported. Flammable liquid when exposed to
heat, sparks, or flame. May explode on
heating. Potentially violent reaction with
sodium methoxide. When heated to
decomDosition it emits very toxic fumes of NOx and Cl-. See also other
chloronitrobenzene entries and NITRO
COMPOUNDS OF AROMATIC
Incineration (816℃, 0.5 second
for primary combustion; 1204℃, 1.0 second for secondary
combustion). The formation of elemental chlorine
can be prevented through injection of steam or methane
into the combustion process. nitrogen oxides may be abated
through the use of thermal or catalytic devices.
Crystallise the nitrobenzene from 95% EtOH (charcoal) and sublime it in vacuo. [Emmons JAm Chem Soc 76 3470 1954, Newman & Forrest J Am Chem Soc 69 1221 1947, Beilstein 5 IV 723.]
p-Nitrochlorobenzene is largely used to produce p-nitrophenol with smaller production of p-nitroaniline.
p-Chloronitrobenzene is extensively used in different industries as an intermediate in the
manufacture of dyes, rubber, and agricultural chemicals. It is incompatible with strong
oxidizers and alkalis
Air & Water Reactions
Insoluble in water.
Manufacture of dyes, rubber, and agricultural
p-Nitrochlorobenzene is made by the nitration of chlorobenzene.
4-Chloronitrobenzene reacts with oxidizing agents. Reacts violently and finally explosively when added to a solution of sodium methoxide in methanol. . Unstable when heated.
Repeated exposure to high levels of p-chloronitrobenzene causes adverse health effects.
The symptoms of toxicity include, but are not limited to, anoxia, unpleasant taste, anemia, methemoglobinemia, hematuria (blood in the urine), spleen, kidney, bone marrow
changes, and reproductive effects. The target organs of p-chloronitrobenzene poisoning
have been identifi ed as the blood, liver, kidneys, cardiovascular system, spleen, bone
marrow, and reproductive system.
The annual production of p-CNB in the United States in 1993
was 35,000 metric tons and on the order of 50,000–70,000
metric tons in Germany. It is used as an intermediate in
the manufacture of dyes, rubber, and agricultural chemicals.
Human exposure may occur to dyestuff workers but the
extent is uncertain because of its use as a chemical intermediate.
p-Chloronitrobenzene has been detected in the surface
water of the Rhine River at a concentration range of
4-Chloronitrobenzene is combustible.
p-Nitrochlorobenzene (PNCB) is used
as an intermediate in pesticide (parathion) manufacture,
drug (phenacetin and acetaminophen) manufacture; and in
dye making; rubber and antioxidant manufacture.
A questionable carcinogen. Very toxic by
inhalation and ingestion. Absorbed via skin. Combustible. Methemoglobinemia.
The Journal of Organic Chemistry, 52, p. 2407, 1987 DOI: 10.1021/jo00388a014Tetrahedron Letters, 19, p. 4519, 1978
No increase in tumor incidence was seen
in rats fed up to 1000 ppm in the diet for 2
years; in mice, results were equivocal, with
high-dose animals showing an increase in vascular
tumors and low-dose males showing an
increase in liver tumors.6 The IARC has determined
that there is inadequate evidence in
experimental animals and humans for the carcinogenicity
Light yellow crystalline solid. Density 1.520 g / cm3. Melting point 83°C. Sweet odor. Very toxic by inhalation, ingestion, and skin absorption. p-Chloronitrobenzene is extensively used in different industries as an intermediate in the manufacture of dyes, rubber, and agricultural chemicals. It is incompatible with strong oxidisers and alkalis.
light yellow crystals