Cymene describes organic compounds with the formula , condensed formula . Three isomers exist: 1,2- 1,3-, and 1,4-. All are colorless liquids, immiscible in water, with similar boiling points. They are classified as aromatic hydrocarbons. They bear two substituents: an isopropyl () group and a methyl group. Cymenes Name o-Cymene m-Cymene p-Cymene Structural formula CAS number 527-84-4 535-77-3 99–87–6 melting point (°C) −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:
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.
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