These common heterocyclic compound, 1904-31-0, name is 1-Methyl-1H-pyrazol-3-amine, its 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. Quality Control of 1-Methyl-1H-pyrazol-3-amine
Step 1: (S) -tert-Butyl (1- (2- (3- (cyclopropylmethoxy) -4- (difluoromethoxy) phenyl) -4- ( (1-methyl-1H-pyrazol-3-yl) carbamoyl) oxazol-5-yl) ethyl) carbamate[2043]To 15 mL of dichloromethane were added (S) -5- (1- ( (tert-butoxycarbonyl) amino) ethyl) -2- (3- (cyclopropylmethoxy) -4- (difluoromethoxy) phenyl) oxazole-4-carboxylic acid (250 mg, 0.53 mmol) , 3-amino-1-methylpyrazole (62 mg, 0.64 mmol) , 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (153 mg, 0.80 mmol) and 1-hydroxy-7-azabenzotriazole (182 mg, 1.33 mmol) . To the mixture was added N, N-diisopropylethylamine (0.37 mL, 2.14 mmol) dropwise at 0 . The resulting mixture was stirred at rt for 3.5 hours. The reaction mixture was washed with water (10 mL × 2) and the organic layer was dried over anhydrous sodium sulfate. The organic solvent was removed and the residue was purified by silica gel column chromatography (PE/EtOAc (v/v) 2/1) to give a white solid (260 mg, 85) .[2044]1H NMR (400 MHz, CDCl3) : delta ppm 7.59 (s, 1H) , 7.58 ?7.55 (m, 1H) , 7.31 (d, J 2.1 Hz, 1H) , 7.25 (d, J 8.8 Hz, 1H) , 6.79 (d, J 2.2 Hz, 1H) , 6.71 (t, JF-H 75.1 Hz, 1H) , 5.36 ?5.32 (m, 1H) , 4.00 (d, J 7.0 Hz, 2H) , 3.86 (s, 3H) , 1.56 (d, J 7.0 Hz, 3H) , 1.43 (s, 9H) , 1.37 ?1.32 (m, 1H) , 0.73 ?0.68 (m, 2H) , 0.46 ?0.42 (m, 2H) and MS-ESI: m/z 548.8 [M+H]+.
The synthetic route of 1-Methyl-1H-pyrazol-3-amine has been constantly updated, and we look forward to future research findings.
Reference:
Patent; SUNSHINE LAKE PHARMA CO., LTD.; LIU, Bing; YU, Tianzhu; ZHANG, Yingjun; ZHANG, Xiangyu; ZHANG, Shiguo; CHENG, Changchung; ZHANG, Jiancun; WO2015/161830; (2015); A1;,
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