反应详情

温度

0 °C

Phosphorus pentachloride (4.67 g, 22.4 mmol) is placed in a three neck round bottom flask and cooled to 0° C. Chlorosulfonic acid (6.53 g, 56.0 mmol) is added slowly. The reaction is stirred until the fuming action stops and the reaction mixture becomes clear. Then a solution of 3-ethyl-6-methyl-5-(thiophen-2-yl)-1H-pyridin-2-one (4.92 g, 22.4 mmol) of the above reaction in chloroform (35 mL) is added dropwise, and stirring at 0° C. is maintained for 5 min, then at room temperature. After 30 min, the reaction is poured into ice water (200 mL) and extracted with dichloromethane. The organic layer is washed with water, dried (sodium sulfate), filtered and concentrated and the residue is triturated with hepatane-30% ethyl acetate to afford the title compound (6.88 g, 97% yield) as a yellow solid. MS: m/e=318 (M+H). 1H-NMR (D6-DMSO, δ ppm) 13.2 (br s, 1H); 7.25 (s, 1H); 7.05 (d, 1H, J=3.2 Hz); 6.82 (d, 1H, J=3.2 Hz); 2.39 (q, 2H, J=7.4 Hz); 2.27 (s, 3H); 1.10 (t, 3H, J=7.4 Hz).

1. additionis added dropwise
2. stirringstirring at 0° C.
3. temperatureis maintained for 5 min
4. customat room temperature
5. extractionextracted with dichloromethane
6. washThe organic layer is washed with water
7. dry with materialdried (sodium sulfate)
8. filtrationfiltered
9. concentrationconcentrated
10. customthe residue is triturated with hepatane-30% ethyl acetate