Cymene

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Cymene
p-cymene
IUPAC name 1-methyl-4-(1-methylethyl)benzene
Other names 4-isopropyltoluene
Identifiers
CAS number [99-87-6]
PubChem 7463
EINECS number 202-796-7
SMILES CC(C)c1ccc(C)cc1
InChI InChI=1/C10H14/c1-8(2)10-6-4-9

(3)5-7-10/h4-8H,1-3H3

Properties
Molecular formula C10H14
Molar mass 134.21 g/mol
Appearance Colourless liquid
Density 0.857 g/cm3
Melting point

-68°C

Boiling point

177°C

Solubility in water Negligible
Hazards
R-phrases R10
S-phrases S16
Flash point 47°C
Autoignition
temperature
435°C
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Cymene, or p-cymene, is a naturally occurring aromatic organic compound. It is classified as a hydrocarbon related to a monoterpene. Its structure consists of a benzene ring para-substituted with a methyl group and an isopropyl group. It is insoluble in water, but miscible with ethanol and ether.

Cymene is a constituent of a number of essential oils, most commonly the oil of cumin and thyme.

There are two less common geometric isomers. o-Cymene, in which the alkyl groups are ortho-substituted, and m-cymene, in which they are meta-substituted. p-Cymene is the only natural isomer.

Cymene is a common ligand for ruthenium. The parent compound is [(η6-cymene)MCl2]2. This half-sandwich compound is prepared by the reaction of ruthenium trichloride with the terpene α-phellandrene. The osmium complex is also known.[1]

[edit] References

  1. ^ Bennett, M. A.; Huang, T. N.; Matheson, T. W. and Smith, A. K. (1982). "(h6-Hexamethylbenzene)ruthenium complexes". Inorganic Syntheses 21: 74–8. doi:10.1002/9780470132524.ch16.