Preparation device and preparation method of nicarbazin

Abstract

The invention provides a preparation method of nicarbazin. The preparation method includes the following steps: 1, adding wet paranitroaniline and a solvent into a reaction bottle, and conducting heating, refluxing and water separation; 2, after conducting water distribution, conducting cooling to the room temperature, adding bis(trichloromethyl)carbonate, then conducting heating and stirring to obtain 4, 4'-binitro diphenylcarbamide, and absorbing the generated hydrogen chloride gas with the solvent; 3, adding the liquid absorbing the hydrogen chloride gas as a reaction solvent in another reaction bottle, and adding acetylacetone and urea for a reaction to generate 2-hydroxyl-4,6-dimethyl pyrimidine hydrochloride; 4, regulating the obtained 2-hydroxyl-4,6-dimethyl pyrimidine hydrochloride to be alkaline, then allowing 2-hydroxyl-4,6-dimethyl pyridine hydrochloride to react with 4,4'-binitro diphenylcarbamide in a solution to generate the nicarbazin under the stirring condition, and conducting processing to obtain the finished product of the nicarbazin. The special devices are used and comprise a reaction kettle, a condenser, a gas-liquid separator, a water separator, an anti-inverse-suction one-way valve, an absorption kettle and a second reaction kettle. The raw materials are fully utilized, the product yield is high, the cost is low, and the three wastes are few.

Description

[0001] Technical field: [0002] The invention relates to a nicarbazine preparation technology, mainly designing a nicarbazine preparation device and preparation method. [0003] Background technique: [0004] Nicarbazine (nicarbazin), also known as coccidia net, was developed by Marck Company of the United States in 1955. It has been an effective anticoccidial drug since it came out. It has been used in the world for more than half a century and has been listed in the United States. , Japan and the European Community and other countries veterinary pharmacopoeia, and also included in the Chinese veterinary pharmacopoeia. A large number of tests have proved that nicarbazine is a highly efficient, non-toxic, stable performance, small drug resistance, ideal anticoccidia feed additive, and it is effective against various Eimeria in chickens such as tender, fragile, poisonous giant, Heap shape, Eimeria brucei have good control effect. Another advantage is that it has little or no ...

AI Technical Summary

Problems solved by technology

[0017] Triphosgene can replace phosgene and p-nitroaniline to prepare DNC. During the reaction, in addition to generating DNC, a by-product hydrogen chloride is also generated. Hydrogen chloride will form ammonium salt with p-nitroaniline in the system, making the reaction difficult. completely

[0021] 3. O-dichlorobenzene has a high boiling point and cannot be used for boiling water removal in the system, and it is highly toxic, which is not conducive to labor protection and health

[0022] 4. The "one pot" reaction is carried out in series, the reaction time is long, the efficiency is low, and it is not conducive to quality control

[0026] At present, there are many technologies for studying the synthesis of nicarbazine, but many of them are reduced to theoretical experiments. The methods are uneconomical, the steps are complicated and unreasonable, and the problems of difficulty in realizing effective reactions due to little consideration of raw materials and unutilization of intermediate products are more prominent. These issues must be considered in mass production practice

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