反应详情

To a solution of 1-(pyridin-2-yl)-5-(trifluoromethyl)-1H-pyrazole-4-carboxylic acid (2.57 g, 9.99 mmol) in DMF (30 mL) was added EDC (2.395 g, 12.49 mmol), HOBt (1.913 g, 12.49 mmol) and Hunig's Base (5.24 mL, 30.0 mmol). The reaction was stirred for 40 min. at room temperature, then N-hydroxy-4-(hydroxymethyl)benzimidamide, Int.2, (2.076 g, 12.49 mmol) was added. The reaction mixture was stirred at room temperature for 7 h, then additional EDC (2.395 g, 12.49 mmol), HOBt (1.913 g, 12.49 mmol) and Hunig's Base (5.24 mL, 30.0 mmol) were added. The reaction was heated to 60° C. for 2 h, then at 110° C. for 10 min. 1N aq. HCl was added to adjust the pH to 1, then 30 mL of water was added. The resulting precipitated product was collected by filtration and washed with water to afford (4-(5-(1-(pyridin-2-yl)-5-(trifluoromethyl)-1H-pyrazol-4-yl)-1,2,4-oxadiazol-3-yl)phenyl)methanol (2.28 g, 5.83 mmol, 58%) as a light yellow solid.

1. stirringThe reaction mixture was stirred at room temperature for 7 h
2. temperatureThe reaction was heated to 60° C. for 2 h
3. waitat 110° C. for 10 min
4. customThe resulting precipitated product
5. filtrationwas collected by filtration
6. washwashed with water