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对硝基间甲酚是合成著名低毒高效农药杀螟硫磷(Sumithion)的重要中间体,以往均从纯间甲酚经硝化反应合成,由于纯间甲酚来源有限.最近Hercules公司发表了从混合间对甲酚制取对硝基间甲酚的方法。他们采用间甲酚含量为60%的二混甲酚为原料,硝化后再以苯-亚硫酸钠水溶液萃取,再使对硝基间甲酚结晶析出. 我们认为该法的主要缺点是对甲酚同时被硝化为硝化物.未能综合利用,另外.用苯萃取时耗用大量溶剂,且不安全,而且成本过高.我们经研究提出亚硝化、分离、氧化、再钠盐纯化,克服了上述缺陷.硝化物最后采取钠盐纯化的方法,使它直接与硫代磷酰氯缩合合成杀螟硫磷.
Nitro-m-cresol is an important intermediate for the synthesis of the famous low toxicity and high efficiency pesticide fenitrothion (Sumithion), which have been synthesized from the pure m-cresol by the nitration reaction due to the limited source of the pure m-cresol Recently Hercules published Preparation of p-nitrocresol from p-cresol mixture. They used catechol content of 60% of the two mixed cresol as raw material, nitrification and then benzene - aqueous sodium sulfite extraction, and then p-nitro-m-cresol crystallization.We believe that the main drawback of this method is the cresol at the same time Was nitrified into nitrification. Not comprehensive utilization, the other with benzene extraction consume a large amount of solvent, and unsafe, and the cost is too high. We have proposed nitrosation, separation, oxidation, re-purification of sodium salt to overcome the above Defects.Nitride finally take the method of sodium salt purification, it is directly condensed with thiophosphoryl chloride synthesis fenitrothion.