反应详情

To a solution of ethyl 5-bromothiophene-2-carboxylate (1.5 g, 6.38 mmol) in aqueous conc. H2SO4 (6 ml) cooled to 0° C., aqueous 65% HNO3 (2 ml) was added, and the reaction was left to warm to RT and stirred for 1 hour. The mixture was poured into ice-water and extracted with EtOAc (×3); the combined organic layers were dried over sodium sulfate and the solvent was removed affording ethyl 5-bromo-4-nitrothiophene-2-carboxylate (Int. 40) which was used without any additional purification (550 mg, 1.964 mmol).

1. waitthe reaction was left
2. extractionextracted with EtOAc (×3)
3. dry with materialthe combined organic layers were dried over sodium sulfate
4. customthe solvent was removed