反应详情

温度

0 °C

2-bromo-5-methylsulfonyl-thiophene (0.3 g, 1.24 mmol) was added to the concentrated sulfuric acid at 0° C. cooling in an ice bath. The resulted mixture was stirred at 0° C. for 5 minutes. Then sodium nitrate was introduced and the mixture was stirred at 0° C. for 1 hour. After this time, the reaction mixture was poured onto to the ice-water (10 mL) and was extracted with ethyl acetate. The organic phase was dried (Na2SO4) and concentrated under vacuum. The residue was purified by silica gel chromatography using a mixture of 95:5 hexane and ethyl acetate as eluent to afford the title product as a solid (0.17 g, 47% yield). 1H NMR (400 MHz, d6-DMSO) δ: 8.37 (1H, s), 2.50 (3H, m).

1. temperaturecooling in an ice bath
2. stirringthe mixture was stirred at 0° C. for 1 hour
3. extractionwas extracted with ethyl acetate
4. dry with materialThe organic phase was dried (Na2SO4)
5. concentrationconcentrated under vacuum
6. customThe residue was purified by silica gel chromatography
7. additiona mixture of 95:5 hexane and ethyl acetate as eluent