Cymene

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Cymene describes organic compounds with the formula CH3C6H4CH(CH3)2. Three isomers exist: 1,2- 1,3-, and 1,4-. All are colorless liquids, immiscible in water, with similar boiling points. They are classified are aromatic hydrocarbons. The bearing two substituents: an isopropyl (CH(CH3)2) group and a methyl group. [1]

Cymenes
Name o-Cymene m-Cymene p-Cymene
Structural formula O-Cymol.svg M-Cymol.svg P-Cymol.svg
CAS number 527-84-4535-77-399-87-6
melting point  -71.54 -63.75 -67.94
boiling point (°C)178.15175.05177.10

Production and reactions

m- and p-Cymene are prepared by alkylation of toluene with propylene:

CH3C6H5 + 2 CH3CH=CH2 → CH3C6H4CH(CH3)2

These alkylations are catalyzed by various Lewis acids, such as aluminium trichloride.

m- and p-Cymene are mainly of interest as precursors to the respective cresols, which exploits the Hock rearrangements. [1]

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<i>o</i>-Cymene Organic compound

o-Cymene is an organic compound classified as an aromatic hydrocarbon. Its structure consists of a benzene ring ortho-substituted with a methyl group and an isopropyl group. It is a flammable colorless liquid which is nearly insoluble in water but soluble in organic solvents.

<i>m</i>-Cymene Organic compound

m-Cymene is an organic compound classified as an aromatic hydrocarbon. Its structure consists of a benzene ring meta-substituted with a methyl group and an isopropyl group. It is a flammable colorless liquid which is nearly insoluble in water but soluble in organic solvents.

References

  1. 1 2 Schmidt, Roland; Griesbaum, Karl; Behr, Arno; Biedenkapp, Dieter; Voges, Heinz-Werner; Garbe, Dorothea; Paetz, Christian; Collin, Gerd; Mayer, Dieter; Höke, Hartmut (2014). "Hydrocarbons". Ullmann's Encyclopedia of Industrial Chemistry. pp. 1–74. doi:10.1002/14356007.a13_227.pub3. ISBN   9783527306732.