Production of<i>p</i>-Methylstyrene and<i>p</i>-Divinylbenzene from Furanic Compounds
作者:Maura Koehle、Erisa Saraçi、Paul Dauenhauer、Raul F. Lobo
DOI:10.1002/cssc.201601554
日期:2017.1.10
cycloaddition and dehydration of 2‐ethyl‐5‐methyl‐furan with ethylene over zeolite H‐Beta. Dehydrogenation of p‐ethyltoluene to yield p‐methylstyrene completes the synthesis but was not investigated because it is a known process. The first two steps were accomplished in high yield (>88 %) and the Diels–Alder step resulted in a 67 % yield of p‐ethyltoluene with a 99.5 % selectivity to the para isomer (final yield
开发了一种四步催化工艺,以从生物质来源的物种甲基呋喃生产对甲基苯乙烯。首先,将甲基呋喃用乙酸酐在H-β沸石上酰化。其次,在亚铬酸铜上,用氢将乙酰基还原为乙基。第三,对-乙基甲苯是通过Diels-Alder环加成反应生成的,然后将2-乙基-5-甲基呋喃与乙烯在H-β沸石上脱水。对乙基甲苯脱氢以生成对甲基苯乙烯完成了合成过程,但尚未进行研究,因为这是已知方法。前两个步骤以高收率(> 88%)完成,而Diels–Alder步骤产生了67%的p收率。对乙基异构体的对甲苯异构体的选择性为99.5%(最终产率为53.5%)。该方法还用于制备对二乙烯基苯。结果表明,呋喃在H-Beta沸石上的酰化反应是高度选择性和高产率的反应,可用于从生物质衍生的呋喃中生产其他有价值的分子。