A process for preparing alpha 2, 4 - 5 two chloride (two methyl fluoride) 4, 5 - two 3 - 5 1H1 carbonyl methyl hydrogen, 2, 4 - three - 4: triazole based fluorobenzene ethyl propionate (product) method, which is characterized in that the 4 - two fluorine methyl 4, 5 - two - 5 - 3 - methyl carbonyl hydrogen (- 1 - 5 - amino - 2 - F - 4 - chlorophenyl) - 1H - 1, 2, 4 - three triazole (amine) diazotized with ethyl acrylate and the aryl amine diazotization reaction was performed at the same time, by the following 5 steps, in addition to outside amine the amount of components are expressed as molar equivalents corresponding to the 1 molar equivalent of amine (a): after adding acetone 10 - 30 equivalent amine solution agitation in 0.05 and 0.5 (the equivalent of cuprous chloride; B) the solution temperature is reduced to 20 to 30 DEG C, keeping the temperature in this range, stirring while adding enough hydrochloric acid into the amine hydrochloride; (c) will be maintained at a temperature below 10 DEG C, ethyl acrylate add 5 - 20 equivalent to the resultant slurry stirring in (d); after the adjustment of the stirring of the reaction mixture temperature to 0 DEG C, and then to control the temperature of about 20 degrees Celsius, sodium nitrite added 1 to 2 equivalent, which lasted 1 to 6 hours, then, continue stirring for 15 to 90 minutes; (E) recycling products.
【技术实现步骤摘要】
本专利技术涉及除草剂α-2-二氯-5-[4-(二氟甲基)-4,5-二氢-3-甲基-5-羰基-1H-1,2,4-三唑-1-基]-4-氟苯丙酸乙酯的制备方法的最后一步,即米尔文(Meerwein)重氮化和芳基化反应。美国专利5,125,958号揭示了具有以下结构的除草剂。 常用的方法中米尔文重氮化和芳基化反应往往由2个步骤完成。首先,芳胺在水溶液,如亚硝酸钠水溶液中被重氮化,然后,将重氮化后的胺溶液添加到待进行芳基化的化合物的溶液中。在美国专利5,125,958号中,制备除草剂的最后一步包括4-二氟甲基-4,5-二氢-3-甲基-5-羰基-1-(5-氨基-2-氟-4-氯苯基)-1H-1,2,4-三唑这一胺的重氮化步骤。但是,发现在水溶液中进行此胺的重氮化反应时,2-氟取代基被水解成相应的酚而消失,所以,以上专利所述的重氮化反应由传统的2步反应完成,但反应在非水溶性介质中进行,并将亚硝酸叔丁酯作为亚硝酸根的来源。然后,将经重氮化的胺添加到丙烯酸乙酯(芳基化)就得到了目的产物除草剂。这种制备方法只能够满足实验室中少量生产,不能够满足大量的生产和工业生产。这不仅是因为亚硝酸叔丁 ...
【技术保护点】
【技术特征摘要】
1.一种制备α-2-二氯-5-[4-(二氟甲基)-4,5-二氢-3-甲基-5-羰基-1H-1,2,4-三唑-1-基]-4-氟苯丙酸乙酯(产物)的方法,其特征在于,4-二氟甲基-4,5-二氢-3-甲基-5-羰基-1-(5-氨基-2-氟-4-氯苯基)-1H-1,2,4-三唑(胺)的重氮化与丙烯酸乙酯和经重氮化的胺的芳基化是同时进行的,反应由以下5步完成,其中除胺之外的组分的量都表示为对应于1摩尔当量胺的摩尔当量(a)在经过搅拌的胺溶液中加入10-30当量的丙酮和0.05-0.5当量的氯化亚铜;(b)将溶液的温度降至-20-30℃,保持温度在此范围内,边搅拌边添加足够的盐酸使胺转变为盐酸盐;(c)将温度保持在10℃以下,边搅拌边向生成物的淤浆中添加5-20当量的丙烯酸乙酯;(d)将经过搅拌的反应混合物的温度调整到0℃左右,然后将温度控制在约20...
【专利技术属性】
技术研发人员:J·W·阿热,C·A·波尔茨,
申请(专利权)人:FMC有限公司,
类型:发明
国别省市:
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