Sulfuric Acid → 2-Bromo-5-methanesulfonyl-3-nitrothiophene
Reaction equation
[Br:1][C:2]1[S:3][C:4]([S:7]([CH3:10])(=[O:9])=[O:8])=[CH:5][CH:6]=1.S(=O)(=O)(O)O.[N+:16]([O-])([O-:18])=[O:17].[Na+]>>[Br:1][C:2]1[S:3][C:4]([S:7]([CH3:10])(=[O:9])=[O:8])=[CH:5][C:6]=1[N+:16]([O-:18])=[O:17]Participants
4
Conditions
- Temperature
- 0 °C
Procedure
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).