Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States.
J Am Chem Soc. 2012 Sep 26;134(38):15708-11. doi: 10.1021/ja307612b. Epub 2012 Sep 13.
As oil supplies dwindle, there is a growing need to develop new routes to chemical intermediates that utilize alternative feedstocks. We report here a synthesis of para-xylene, one of the highest volume chemicals derived from petroleum, using only ethylene as a feedstock. Ethylene is an attractive alternative feedstock, as it can be derived from renewable biomass resources or harnessed from large domestic shale gas deposits. The synthesis relies on the conversion of hexene (from trimerization of ethylene) to 2,4-hexadiene followed by a Diels-Alder reaction with ethylene to form 3,6-dimethylcyclohexene. This monoene is readily dehydrogenated to para-xylene uncontaminated by the ortho and meta isomers. We report here a selective synthesis of para-xylene, uncontaminated by the ortho or meta isomers, using ethylene as the sole feedstock.
随着石油供应的减少，人们越来越需要开发利用替代原料生产化学中间体的新途径。在这里，我们报告了一种仅使用乙烯作为原料生产对二甲苯（一种源自石油的最大宗化学品）的方法。乙烯是一种很有吸引力的替代原料，因为它可以从可再生生物质资源中获得，也可以从国内大型页岩气储量中提取。该合成方法依赖于将己烯（由乙烯三聚化得到）转化为 2,4-己二烯，然后与乙烯进行 Diels-Alder 反应生成 3,6-二甲基环己烯。这种单烯很容易脱氢生成对二甲苯，不会被邻位和间位异构体污染。在这里，我们报告了一种使用乙烯作为唯一原料的选择性合成对二甲苯的方法，不会被邻位或间位异构体污染。
