Nitric Acid → 2,5-Dibromo-3-nitrothiophene

Reaction equation

[Br:1][C:2]1[S:3][C:4]([Br:7])=[CH:5][CH:6]=1.[N+:8]([O-])([OH:10])=[O:9].S(=O)(=O)(O)O>>[Br:1][C:2]1[S:3][C:4]([Br:7])=[CH:5][C:6]=1[N+:8]([O-:10])=[O:9]

Participants

Reactant 3

HCID 944Nitric Acid

HCID 1118Sulfuric Acid

HCID 184532,5-Dibromothiophene

Product 1

HCID 49618952,5-Dibromo-3-nitrothiopheneYield 13.7%

Conditions

Temperature: 0 °C

Procedure

2,5-dibromothiophene (10.0 g, 0.0413 mol) was added in portions to nitric acid (38 mL) and concentrated sulfuric acid (75 mL) cooled at 0° C. with an ice bath. On complete addition, the reaction was removed from the cold bath and was stirred for 30 minutes before the reaction mixture was poured onto ice water (400 mL) and extracted with ethyl acetate. The organic layer was separated, dried (Na2SO4), concentrated under vacuum and the residue purified by silica gel chromatography to afford the title product as solid (1.6 g, 13.7% yield).