Mesitylene

Mesitylene


IUPAC name	1,3,5-Trimethylbenzene
Other names	Mesitylene sym-Trimethylbenzene
Identifiers
CAS number	[108-67-8]
EINECS number	203-604-4
SMILES	c1(C)cc(C)cc(C)c1
Properties
Molecular formula	C₉H₁₂
Molar mass	120.19 g/mol
Density	0.8637 g/cm³ at 20 °C
Melting point	-44.8 °C
Boiling point	164.7 °C
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

In organic chemistry, mesitylene or 1,3,5-trimethylbenzene (C₉H₁₂) is an aromatic hydrocarbon with three methyl substituents attached to the benzene ring. It is prepared from distillation of acetone with sulfuric acid or by the trimerization of propyne in sulfuric acid, which in both cases acts as a homogeneous catalyst and dehydrating agent. It is commonly used as a solvent in research and industry. Mesitylene is flammable and an irritant. Mesitylene has a very low freezing point.

In the electronics industry, mesitylene has also been used as a developer for photopatternable silicones due to its solvent properties.

1,3,5-Trimethylbenzene is also a major urban volatile organic compound (VOC) which results from combustion. It plays a significant role in aerosol and tropospheric ozone formation as well as other reactions in atmospheric chemistry.

The mesityl group (Mes) is a functional group found as an attachment in many organic compounds.