ethyltoluene
{{Short description|Organic compounds with the empirical formula CH3C6H4CH2CH3}}
Ethyltoluene describes organic compounds with the formula {{chem2|CH3C6H4CH2CH3}}. 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 ring bears two substituents: a methyl group and an ethyl group.
| class="wikitable" style="text-align:center; font-size:90%"
| colspan="4" class="colspan="4"" | Cymenes |
| Name
| 2-ethyltoluene || 3-ethyltoluene || 4-Ethyltoluene |
|---|
| Structural formula |
| CAS number
| 611-14-3 || 620-14-4 || 622-96-8 |
| melting point (°C)
| −80.8 || −95.5 || −62.3 |
| boiling point (°C)
| 165 || 161.3 || 162 |
Production and reactions
Ethyltoluenes are prepared by alkylation of toluene with ethylene:
:{{chem2|CH3C6H5 + CH2\dCH2 -> CH3C6H4CH2CH3}}
These alkylations are catalyzed by various Lewis acids, such as aluminium trichloride.
3- and 4-Ethyltoluenes are mainly of interest as precursors to methylstyrenes:
:{{chem2|CH3C6H4CH2CH3 -> CH3C6H4CH\dCH2 + H2}}
This dehydrogenation is conducted in the presence of zinc oxide catalysts.{{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 }}