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|Section2= |Section3= }} Durene, or 1,2,4,5-tetramethylbenzene, is an organic compound with the formula C6H2(CH3)4. It is a colourless solid with a sweet odor. The compound is classified as an alkylbenzene. It is one of three isomers of tetramethylbenzene, the other two being prehnitene (1,2,3,4-tetramethylbenzene, m.p. −6.2 °C) and isodurene (1,2,3,5-tetramethylbenzene, m.p. −23.7 °C). Durene has an unusually high melting point, reflecting its high molecular symmetry.〔Karl Griesbaum, Arno Behr, Dieter Biedenkapp, Heinz-Werner Voges, Dorothea Garbe, Christian Paetz, Gerd Collin, Dieter Mayer, Hartmut Höke “Hydrocarbons” in Ullmann's Encyclopedia of Industrial Chemistry, 2002 Wiley-VCH, Weinheim. 〕 ==Production== It is a component of coal tar. It is produced by methylation of other methylated benzene compounds such as p-xylene and pseudocumene.〔Durene was first prepared in 1870 from pseudocumene. See: Paul Jannasch and Rudolph Fittig (1870) ("Ueber das Tetramethylbenzol" ) (On tetramethylbenzene), ''Zeitschrift für Chemie'', 6 : 161-162.〕 :C6H4(CH3)2 + 2 CH3Cl → C6H2(CH3)4 + 2 HCl In industry, a mixture of xylenes and trimethylbenzenes is alkylated with methanol. Durene can be separated from its isomers by selective crystallization, exploiting its high melting point.〔 The original synthesis of durene involved a similar reaction starting from toluene.〔E. Ador and A. Rilliet "Ueber durch Einwirkung von Chlormethyl auf Benzol in Gegenwart von Aluminiumchlorid erhaltene Kohlenwasserstoffe" Chem. Ber. 1879, volume 12, pages 329–332. 〕 Durene is a significant byproduct of the production of gasoline from methanol via the "MTG (Methanol to Gasoline) process".〔(【引用サイトリンク】title=The Production of Methanol and Gasoline )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Durene」の詳細全文を読む スポンサード リンク
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