Sulfuric Acid → Methyl 5-bromo-3-nitrothiophene-2-carboxylate

Participants

Reaction Steps

Sulfuric acid (98% strength; 12 mL) was added to a solution of 3-nitrothiophene-2-carboxylic acid methyl ester (Barker et al., Synth. Commun. 1995, 25, 3729; 20.8 g) in trifluoroacetic acid (60 mL). At 0° C., N-bromosuccinimide (21.9 g) was added in portions over a period of 45 minutes. After a further 30 minutes, the mixture was warmed to room temperature and poured into ice-water. The organic phase obtained by extraction with dichloromethane was dried over magnesium sulfate and concentrated. The residue was purified by chromatography on silica gel. The product with the molecular weight of 266.07 (C6H4BrNO4S) was obtained in this way; MS (ESI): 266 (M+H+).

Provenance & Evidence