反应详情

温度

0 °C

4-Chloro-2-(pyridin-3-yl)thiazole (1.00 g, 5.09 mmol) was placed in a dry flask and concentrated H2SO4 (2.50 g, 25.4 mmol) was added. The contents were cooled to 0° C., and fuming HNO3 (641 mg, 10.17 mmol) was slowly added. The mixture was stirred at 40° C. for 3 h and cooled to room temperature. The contents were slowly added to an ice-cold saturated aqueous solution of NaHCO3. The mixture was extracted with ethyl acetate (2×50 mL) and the extracts were combined, rinsed with brine and concentrated in vacuo to give 4-chloro-5-nitro-2-(pyridin-3-yl)thiazole as a peach-colored solid (985 mg, 80% yield): mp 110-112° C.; 1H NMR (300 MHz, CDCl3) 9.18 (d, J=2.1 Hz, 1H), 8.81 (dd, J=5.1, 1.8 Hz, 1H)), 8.27 (ddd, J=7.3, 4.2, 2.4 Hz, 1H), 7.49 (dd, J=7.8, 5.1 Hz, 1H); EIMS m/z 241 ([M+H])+.

1. temperaturecooled to room temperature
2. extractionThe mixture was extracted with ethyl acetate (2×50 mL)
3. washrinsed with brine
4. concentrationconcentrated in vacuo