反应详情

To a stirred solution of 1-methyl-5-pyridin-2-yl-1H-pyrazole-3-carboxylic acid ethyl ester (655 mg, 2.8 mmol) at r.t. in ethanol (6 ml) under an argon atmosphere was added 1 N NaOH (5.7 ml) in one portion. The mixture was stirred at r.t. for 5 hrs, neutralized by the addition of 1 N HCl and concentrated to leave a light brown solid. This was triturated in a mixture of Et2O (10 ml) and EtOH (1 ml). The suspension was stirred at r.t. for 2 h. The solids was collected by filtration, washed with Et2O and dried to give the title compound (0.79 g, 100% with 73% purity; impurity: NaCl) as light brown solid. MS: M=204.2 (M+H)+

1. concentrationconcentrated
2. customto leave a light brown solid
3. customThis was triturated in a mixture of Et2O (10 ml) and EtOH (1 ml)
4. stirringThe suspension was stirred at r.t. for 2 h
5. filtrationThe solids was collected by filtration
6. washwashed with Et2O
7. customdried