{{for|the ancient Greek city|Cymene (Thessaly)}} '''Cymene''' describes organic compounds with the formula {{chem2|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 ({{chem2|CH(CH3)2}}) group and a methyl group.<ref name=HC>{{cite book |doi=10.1002/14356007.a13_227.pub3 |chapter=Hydrocarbons |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2014 |last1=Schmidt |first1=Roland |last2=Griesbaum |first2=Karl |last3=Behr |first3=Arno |last4=Biedenkapp |first4=Dieter |last5=Voges |first5=Heinz-Werner |last6=Garbe |first6=Dorothea |last7=Paetz |first7=Christian |last8=Collin |first8=Gerd |last9=Mayer |first9=Dieter |last10=Höke |first10=Hartmut |pages=1–74 |isbn=9783527306732 }}</ref> {|class="wikitable" style="text-align:center; font-size:90%" | colspan="4" class="colspan=&quot;4&quot;" | '''Cymenes''' |- ! Name | ''o''-Cymene || ''m''-Cymene || ''p''-Cymene |- ! Structural formula | 110px || 110px || 90px |- ! 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: :{{chem2|CH3C6H5 + 2 CH3CH\dCH2 -> 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.<ref name=HC/>

==References== {{Reflist}}

{{Hydrocarbons}}

Category:Alkylbenzenes Category:C4-Benzenes Category:Monoterpenes Category:Isopropyl compounds

{{Organic-chem-stub}}