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 round botom flask, 100 mL of ethanol was added, (30 mmol) of pivaloylacetonitrile, (33.63 mmol) of 4-methylphenylhydrazine, A solution of 3.6 mL of concentrated hydrochloric acid was added dropwise with stirring,Heated to reflux for 8 hours, cool down, concentrate, The residue was adjusted to pH 10-11 with dilute sodium hydroxide, Extracted three times with ethyl acetate, Dried over anhydrous sodium sulfate, concentrate, 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 a 100 ml three-Dissolved in 30 ml of tetrahydrofuran, Place the three-necked flask in a cryogenic tank to cool to -20 C, 2.9 g of sodium bicarbonate was added in portions with stirring, After 15 min, A solution of trichloroethyl chloroformate (3.5 mmol) was added dropwise, Control the solution temperature does not exceed 0 deg C, After dripping, Continue stirring for 30min, And then heated to 0 C for 12 h. After completion of the reaction, The mixture is filtered, The residue was washed with ethyl acetate, The filtrate was concentrated, 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.