反应详情

To a stirred solution of 5-phenyl-1H-pyrazole-3-carboxylic acid (1.25 g, 0.00665 mol) in DMF (3 mL) was added DIPEA (4.296 g 0.03324 mol), HOBt (1.123 g, 0.00831 mol) and EDCI.HCl (1.593 g, 0.00831 mol) at ambient temperature. After 2 minutes glycine acid ethyl ester hydrochloride (0.928 g, 0.00665 mol) was and the resulting mixture was stirred overnight. The reaction mixture was then diluted with cold water and the product was extracted with ethyl acetate. The ethyl acetate layer was collected and washed with brine solution, dried over sodium sulfate and concentrated under reduced pressure to afford 0.76 g (42% of [(5-phenyl-1H-pyrazole-3-carbonyl)-amino]-acetic acid ethyl ester. LCMS: 274.11 (M+1)+, 96.7%. To a stirred solution of [(5-phenyl-1H-pyrazole-3-carbonyl)-amino]-acetic acid ethyl ester (0.615 g, 0.0025 mol) in a mixture of THF (10 mL), methanol (5 mL) and H2O (5 mL) was added LiOH.H2O (0.283 g, 0.00675 mol) at ambient temperature. The reaction mixture was stirred at the same temperature for 2 hours. Volatiles were evaporated and the residue was diluted with water, acidified with 10% HCl solution. The resulting precipitate was isolated by filtration, washed water followed by hexane and to afford 0.238 g (38%) of [(5-phenyl-1H-pyrazole-3-carbonyl)-amino]-acetic acid. LCMS: 246.08 (M+1)+, 95.60%

1. customVolatiles were evaporated
2. additionthe residue was diluted with water
3. customThe resulting precipitate was isolated by filtration
4. washwashed water