反应详情

温度

25 °C

To a solution of 4-(trifluoromethyl)thiazole-2-carbonitrile (0.9 g, 5 mmol) and TEA (1.1 mL, 7.5 mmol) in DCM (20 mL) was added hydroxylamine hydrochloride (0.35 g, 5 mmol), then the mixture was stirred at 25° C. for 2 hours. The mixture was concentrated in vacuo and the residue was purified by a silica gel column chromatography (PETROLEUM ETHER/EtOAc (V/V)=10/1) to give the crude product as a white solid. To the white solid in acetic acid (25 mL) were added Ac2O (0.32 mL, 3.33 mmol) and Pd—C (10%, 0.2 g), then the mixture was stirred at 25° C. for 12 hours under N2. The reaction mixture was filtered and the filtrate was concentrated in vacuo. Then the residue was crystallized from EtOAc (2 mL) and ether (10 mL) to give the title compound as a white solid (0.74 g, 58%). The compound was characterized by the following spectroscopic data:

1. concentrationThe mixture was concentrated in vacuo
2. customthe residue was purified by a silica gel column chromatography (PETROLEUM ETHER/EtOAc (V/V)=10/1)
3. customto give the crude product as a white solid
4. stirringthe mixture was stirred at 25° C. for 12 hours under N2
5. filtrationThe reaction mixture was filtered
6. concentrationthe filtrate was concentrated in vacuo
7. customThen the residue was crystallized from EtOAc (2 mL) and ether (10 mL)