Cymene

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
CAS number 527-84-4 535-77-3 99-87-6
melting point  -71.54  -63.75  -67.94
boiling point (°C) 178.15 175.05 177.10

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]

References

  1. ^ a b 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.
  • v
  • t
  • e
Hydrocarbons
Saturated
aliphatic
hydrocarbons
Alkanes
CnH2n + 2
Linear alkanes
Branched alkanes
Cycloalkanes
Alkylcycloalkanes
Bicycloalkanes
Polycycloalkanes
Other
  • Spiroalkanes
Unsaturated
aliphatic
hydrocarbons
Alkenes
CnH2n
Linear alkenes
Branched alkenes
Alkynes
CnH2n − 2
Linear alkynes
Branched alkynes
  • Isopentyne
  • Isohexyne
  • Isoheptyne
  • Isooctyne
  • Isononyne
  • Isodecyne
Cycloalkenes
Alkylcycloalkenes
Bicycloalkenes
Cycloalkynes
Dienes
Other
Aromatic
hydrocarbons
PAHs
Acenes
Other
Alkylbenzenes
C2-Benzenes
Xylenes
  • o-Xylene
  • m-Xylene
  • p-Xylene
Other
C3-Benzenes
Trimethylbenzenes
Other
C4-Benzenes
Cymenes
  • o-Cymene
  • m-Cymene
  • p-Cymene
Tetramethylbenzenes
Other
Other
Vinylbenzenes
Other
Other


Stub icon

This organic chemistry article is a stub. You can help Wikipedia by expanding it.

  • v
  • t
  • e