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2,6-二甲基苯酚是重要的化工原料和精细化工中间体,可以用作合成工程塑料聚苯醚和改性聚苯醚的单体,也可用于高温环氧树脂、农药的生产,还可作照相用药剂,同时还是一些药物的原料和中间体,如抗心律失常药慢心律及维生素E等。2,6-二甲基苯酚的合成国内外已有报道,主要有苯酚的氨甲基化法、卤代苯酚的取代、二甲苯的氧化,但条件都比较苛刻。现在多采用苯酚和邻甲酚与甲醇在催化剂存在下于气相状态下进行反应,催化剂多用氧化镁等金属氧化物,需在高温下反应,且选择性不高,会产生很大比例的对位产物,使质量受到影响。有文献报道用2,6-二甲基苯胺为原料,经重氮化、水解而得产物,水解都是在浓酸(80%的浓度)和高温(160℃)下反应,焦油多、副产物多,本文对此法进行了研究改进,在催化剂硫酸铜的存在下,使水解条件变得温和,水解液可以重复使用,降低了成本,提高了收率,具有重要的应用价值。
2,6-dimethylphenol is an important chemical raw materials and fine chemical intermediates, can be used as synthetic engineering plastics polyphenylene ether and modified polyphenylene ether monomer, can also be used for high temperature epoxy resin, pesticide production, Also for photographic agents, but also some of the raw materials and intermediates, such as anti-arrhythmic drugs slow heart rate and vitamin E and so on. The synthesis of 2,6-dimethylphenol has been reported at home and abroad, mainly with the amino methylation of phenol, halogenated phenol substitution, xylene oxidation, but the conditions are harsh. Now more use of phenol and o-cresol and methanol in the presence of a catalyst in the gas phase reaction, the catalyst with magnesium oxide and other metal oxides, to be reacted at high temperatures, and the selectivity is not high, will have a large proportion of para The product, the quality is affected. It has been reported in the literature that 2,6-dimethylaniline is used as a raw material, diazotized and hydrolyzed to give the product. The hydrolysis is carried out under concentrated acid (80% concentration) and high temperature (160 ° C) More products, this article has been studied to improve the catalyst in the presence of copper sulfate, the hydrolysis conditions become mild, the hydrolyzate can be reused, reducing costs and increase yield, has important application value.