1,3,5-Trichlorobenzene

Description

Trichlorobenzenes (TCBs) are synthetic chemicals that occur in three different isomeric forms. The three chlorinated cyclic aromatic isomers are 1,2,3-trichlorobenzene (1,2,3-TCB), 1,2,4-trichlorobenzene (1,2,4-TCB), and 1,3,5-trichlorobenzene (1,3,5-TCB). 1,2,4-TCB is one of the 188 chemicals designated as a hazardous air pollutant under the Clean Air Act.

Chemical properties

white to beige crystalline powder

The Uses of 1,3,5-Trichlorobenzene

1,3,5-Trichlorobenzene is used for someof these applications plus as a termite preparation and insecticide. These compounds are found as unintended by-products of the manufacture of the mono- and dichlorobenzenes.

The Uses of 1,3,5-Trichlorobenzene

Trichlorobenzenes are primarily used as solvents in chemical manufacturing industries. 1,2,4-Trichlorobenzene is economically the most important isomer. 1,2,4-Trichlorobenzene is used as a solvent in chemical reactions to dissolve oils, waxes, and resins. Furthermore, it is also used as a dye carrier. 1,2,3- Trichlorobenzene is used as an intermediate for pesticides production, pigments, and dyes. 1,3,5-Trichlorobenzene is not marketed commercially and has very limited use as a chemical intermediate. Besides, trichlorobenzenes can also be used as degreasing agents, as septic tanks and drain cleaners, and as an ingredient in wood preservatives and abrasive formulations. Other minor uses include metal work, anticorrosive paint, and corrosion inhibitor in sprays. In the past, mixed isomers of trichlorobenzenes were used to control termites; however, their use has been discontinued.

The Uses of 1,3,5-Trichlorobenzene

1,3,5-Trichlorobenzene is an isomer of 1,2,4-Trichlorobenzene (T774220) which is a solvent in various organic chemical reactions.

Definition

ChEBI: 1,3,5-trichlorobenzene is a trichlorobenzene carrying chloro substituents at positions 1, 3 and 5.

General Description

White to off-white crystals.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

Can react vigorously with oxidizing materials. .

Fire Hazard

1,3,5-Trichlorobenzene is combustible.

Safety Profile

Moderately toxic by ingestion and intraperitoneal routes. Mutation data reported. When heated to decomposition it emits toxic vapors of Cl-.

Environmental Fate

Biological. Under aerobic conditions, soil microbes degraded 1,3,5-trichlorobenzene to 1,3- and 1,4-dichlorobenzene and carbon dioxide (Kobayashi and Rittman, 1982). A mixed culture of soil bacteria or a Pseudomonas sp. transformed 1,3,5-trichlorobenzene to 2,4,6-trichlorophenol (Ballschiter and Scholz, 1980).
In an enrichment culture derived from a contaminated site in Bayou d’Inde, LA, 1,3,5- trichlorobenzene underwent reductive dechlorination yielding 1,3-dichlorobenzene. The maximum dechlorination rate, based on the recommended Michaelis-Menten model, was 9.5 nM/d (Pavlostathis and Prytula, 2000).
Photolytic. The sunlight irradiation of 1,3,5-trichlorobenzene (20 g) in a 100-mL borosilicate glass-stoppered Erlenmeyer flask for 56 d yielded 160 ppm pentachlorobiphenyl (Uyeta et al., 1976). A photooxidation half-life of 6.17 months was reported for the vapor-phase reaction of 1,3,5-trichlorobenzene with OH radicals (Atkinson, 1985).

Purification Methods

Recrystallise it from dry *benzene or toluene. [Beilstein 5 IV 666.]

Toxicity evaluation

The liver is themain target of trichlorobenzenes irrespective of the route of exposure. The mechanisms of liver toxicity induced by these chemicals have not been illustrated. It might involve intermediate arene oxides formed during initial transformation to trichlorophenols. In addition, exposure to 1,2,4-TCB induced porphyria in rats by inducing daminolevulinic acid (ALA) synthetase, a rate-limiting enzyme in the biosynthesis of heme, and also heme oxygenase, a ratelimiting enzyme in the degradation of heme synthetase, and therefore increasing heme production.