CAS号 [610-67-3] 生产工艺 邻硝基苯乙醚
CAS名: Benzene, 1-ethoxy-2-nitro- 历史参考文献: Beil. 未检索。
用途: 香料。染料:如冰染偶合组分等。 反应类别: 见反应式。
BIOS 1153, 16-18. (=胶卷PB 85687) o-Nitrophenetole. (Leverkusen). 英国人译自德文(无资料来源)
Plant: 略。 Process: 5000 l. of ethanol 94% and 2000 kg, of o-chloronitrobenzene are charged to the reaction vessel, an air stream of 60 m2 passed through, and the contents heated to 76℃. Ethanol condensed in the condenser is returned to the reaction vessel. The exhaust air is passed through the scrubbing tower and freed from ethanol by washing with water. The wash from the tower is ca. 10% ethanol which is later recovered by distillation.
The dissolving vessel contains 2000 l. of ethanol containing 8-10% of caustic soda, heated to 35-40℃.
When the ethanol is refluxing, the ethanol condensate is directed to the caustic dissolving vessel by means of a 3 way cock, when it dissolves caustic soda and returns to the reaction vessel. When the caustic soda content has fallen to below 6%, after 2-4 hours, a fresh charges of caustic soda (ca. 200 kg.) is charged to the solution vessel. Altogether 820 kg. of caustic soda are required for the reaction. The ethanol reflux is returned to the reaction vessel during the caustic addition.
The temperature in the reaction vessel gradually rises to a maximum of 78℃. The temperature is not allowed to rise above this (by controlling the rate of caustic soda addition, and also the steam flow) other-wise side reactions occur (formation of azoxy-compounds) and the product is worthless.
The pressure in the vessel during the preparation of o-nitrophenetole from o-chloronitrobenzene, is not allowed to rise above 66-80 mm./Hg.
The rate of caustic soda / ethanol addition is controlled by titration of the reation mass; the alkalinity must not exceed 2% caustic soda.
Agitation must in on case be allowed to stop and before starting a batch the driving belt is teated for its trustworthiness. When reaction is complete the charge must be blown to the autoclave as soon as possible. It is cooled to 30℃. the blow-leg fitted and blown to the autoclave.
The charge is neutralized with 150-170 l. of sulphuric acid 78% (280-290 kg.), 200 kg. of soda ash are added, the autoclave is sealed, and 250 kg. of ethyl chloride are then blown in.
The autoclave is heated by means of steam on the coil to 100℃. during 3 hours and raised to 130℃. during a further 2 hours and maintained at 130℃. for 8 hours. The pressure in the autoclave is 10-12 atm.
Isolation: The completed batch is cooled and allowed to settle. The supernatant liquid is blown through an enclosed filter and the filtrates collected in an agitated vessel. The residue of NaCl, Na2SO4, Na2CO3 and sodium nitrophenate is washed 3-4 times with approx. 1000 l. of ethanol, each wash at 50-60℃., and washes blown through the filter.
The salt residues are dissolved inwater, ethanol recovered by distillation and the aqueous residue blown to drain. (这就是排入下水道!)。
The filtered ethanol solution is distilled with direct steam to recover the ethanol (pressure not more than 120 mm./Hg) and after cooling, the oil is separated from the water. The oil is washed twice with dilute NaOH, followed by water. The washed oil is dried under vacuum and is then again filtered.
Reaction times: 略。 Yield: 1960 kg. C.P. 4℃. = 92% of theory. Organic chlorine content: Not more than 0.2-0.3%.
细田豊 《理论制造染料化学》1957年。 P. 481. o-ニトロフェネト- ル. 译自PB 85687. 不再抄录。
张澍声 《精细化工中间体工业生产技术》 1996年。P. 71-72. 邻硝基苯乙醚。 译自BIOS 1153, 16. 不再抄录。
国内研究动态 :
袁云程 高大彬 冯苏宁 (大工)。 相转移催化制备邻硝基苯乙醚。 [J] 染料工业, 1991, 2, 14.
实验部分: 取邻硝基苯酚35 g,溴乙烷41 g,氢氧化钠11 g,苄基三甲基氯化铵3 g,水50 ml,加入三口瓶内。搅拌,升温至80℃开始反应,3小时后停止反应。产物分两层,上层是有机层,下层为水层。分离,减压蒸馏得邻硝基苯乙醚,收率94.8%,纯度99.9%,沸程121-124℃/5mmHg.
一位已经Out 了的老人。抄录历史文献,是献给年轻人了解产品历史而已,至少你在图书馆已不可能看到这类资料了!
陈忠源 2018年2月7日。 本文地址:http://www.陈忠源化学文库.cn/Article.asp?ID=10000620