5418-51-9Relevant articles and documents
One-pot synthesis method for synthesizing 2-hydroxy-5-nitropyridine
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Paragraph 0027-0031, (2021/05/05)
The invention discloses a one-pot synthesis method for synthesizing 2-hydroxy-5-nitropyridine. The method comprises the following specific reaction steps: adding 2-aminopyridine into concentrated sulfuric acid in batches, controlling the temperature at 10-20 DEG C, adding concentrated nitric acid, keeping the temperature at 40-50 DEG C, and stirring; after nitration is completed, adding reaction liquid into water for quenching, controlling the temperature to be 0-10 DEG C, dropwise adding a sodium nitrite aqueous solution, and carrying out diazo reaction; adding a proper amount of ammonia water to adjust the acid concentration; and filtering the solution after the acid concentration is adjusted, and drying a filter cake to obtain the product. The invention provides a novel preparation method of 2-hydroxy-5-nitropyridine. The method has the advantages that the post-treatment is simple, isomers are separated by utilizing the concentration of acid, and the isomers generated by nitration reaction do not need to be independently purified, the nitration reaction and the diazotization reaction are continuously operated, and thus the waste water generated in the amplified production is greatly reduced, and the production cost is saved; the preparation method is never reported in literatures, is a brand-new preparation method of the 2-hydroxy-5-nitropyridine, and provides a new synthesis thought for similar compounds of the 2-hydroxy-5-nitropyridine.
Preparation method of 2-chloro-5-nitropyridine
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Paragraph 0073-0074; 0092-0093, (2020/06/17)
The invention provides a preparation method of 2-chloro-5-nitropyridine. The preparation method comprises the following steps: preparing 2-hydroxy-5-nitropyridine by taking 2-nitroacetaldehyde diethylacetal as an initial raw material through two methods; and then carrying out a chlorination reaction on the 2-hydroxy-5-nitropyridine and a chlorination reagent to prepare the 2-chloro-5-nitropyridine. The method has the advantages of cheap and accessible raw materials and low cost, does not use a diazotization hydrolysis reaction, is safe, simple and convenient to operate, does not use mixed acid, is less in wastewater yield and environmentally-friendly, does not use a nitration reaction, is high in reaction selectivity, few in side reactions, simple in post-treatment and high in product yield and product, and is suitable for industrial production.
Synthesis of Amides by Nucleophilic Substitution of Hydrogen in 3-Nitropyridine
Amangasieva,Borovlev,Demidov,Avakyan,Borovleva
, p. 867 - 872 (2018/07/31)
3-Nitropyridine reacted with nitrogen-centered carboxylic acid amide anions in anhydrous DMSO in the presence of K3Fe(CN)6 via oxidative nucleophilic substitution of hydrogen to give previously unknown N-(5-nitropyridin-2-yl) carboxa