Electric Literature of 285984-25-0,Some common heterocyclic compound, 285984-25-0, name is 3-(tert-Butyl)-1-(p-tolyl)-1H-pyrazol-5-amine, molecular formula is C14H19N3, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
In a 250 mL pre-flask was added 100 mL of ethanol,(30 mmol) of pivaloylacetonitrile,(33. 63 mmol) of 4-methylphenylhydrazine,3. 6 mL of concentrated hydrochloric acid was added dropwise with stirring, heated under reflux for 8 hours,Cooled, concentrated, the residue adjusted with dilute sodium hydroxide PH10-11,Extracted three times with ethyl acetate, dried over anhydrous sodium sulfate, concentrated,The resulting solid was recrystallized from ethyl acetate / petroleum ether to give white crystals C,Yield 80.3%. 5-tert-butyl-2-p-methylphenyl-3-aminopyrazole (3. 5 mmolC) was placed in 100 ml three-necked flask and dissolved in 30 ml of tetrahydrofuran. The three-necked flask was allowed to cool to -20 C, stirring in batches by adding 2. 9g sodium bicarbonate, 15min, dropwise trichloroethyl chloroformate(3. 5 mmol),Control solution temperature does not exceed C,After completion of the dropwise addition, the mixture was stirred for 30 min and then heated to 0 C for 12 h. After completion of the reaction, the mixture was filtered and the residue was rinsed with ethyl acetate and the filtrate was concentrated to yield 85%
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-(tert-Butyl)-1-(p-tolyl)-1H-pyrazol-5-amine, its application will become more common.
Reference:
Patent; institute of pharmacology and toxicology of AMMS; Zhong, Wu; Li, Song; Zhu, Dianxi; LI, Xing-zhou; Zhou, Xin-bo; Wang, Xiaokui; (44 pag.)CN106518767; (2017); A;,
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