Cymene describes organic compounds with the formula C10H14, condensed 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 as aromatic hydrocarbons. They bear two substituents: an isopropyl (CH(CH3)2) group and a methyl group.
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.
References