1,2,4,5-Tetramethylbenzene

white to brown semi-transparent crystals

Colorless crystals or scales with a camphor-like odor

Plasticizers; polymers; fibers; organic synthesis.

1,2,4,5-Tetramethylbenzene is used in method for reducing odor in room in remodeling work by removing causative substances.

ChEBI: Durene is a tetramethylbenzene carrying methyl groups at positions 1, 2, 4 and 5.

Colorless crystals with a camphor-like odor.

Insoluble in water.

Vigorous reactions, sometimes amounting to explosions, can result from the contact between aromatic hydrocarbons, such as 1,2,4,5-Tetramethylbenzene, and strong oxidizing agents. They can react exothermically with bases and with diazo compounds. Substitution at the benzene nucleus occurs by halogenation (acid catalyst), nitration, sulfonation, and the Friedel-Crafts reaction.

Even tetramethylbenzene is one of the components of coal tar, originally prepared from metatrimethylbenzene in 1870. It is obtained by the methylation reaction of other toluene, such as p-xylene or meta-trimethylbenzene.
C6H4(CH3)2 + 2CH3Cl → C6H2(CH3)4 + 2 HCl
Industrially produced using the alkylation reaction of xylene with trimethylbenzene and methanol. Homotetramethylene can be selectively crystallized from its isomers based on its high melting point. Primitive syntheses include similar reactions with toluene as a feedstock.

Chromatograph durene on alumina, and recrystallise it from aqueous EtOH or *benzene. Zone-refining removes duroaldehydes. Dry it under vacuum. [Yamauchi et al. J Phys Chem 89 4804 1985.] It has also been sublimed in vacuo [Johnston et al. J Am Chem Soc 109 1291 1987]. [Beilstein 5 H 431, 5 I 207, 5 II 329, 5 III 979, 5 IV 1076.]

The initial threshold screening level (ITSL) for 1,2,4,5-tetramethyl benzene is 20 μg/m3 (annual averaging time).