N-bromobutanimide → Methyl 5-bromo-1H-pyrrole-3-carboxylate

Participants

Reaction Steps

A solution (70 mL) of methyl 1H-pyrrole-3-carboxylate (4.48 g) in tetrahydrofuran was cooled to −78° C., N-bromosuccinimide (6.30 g) was added, pyridine (5 drops) was added, and the mixture was left standing in a freezer (−20° C.) for 3 days. The reaction mixture was concentrated under reduced pressure, water was added to the residue and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane-ethyl acetate=9:1→1:1) to give the title compound as a pale-yellow solid (yield 3.59 g, 49%).

Provenance & Evidence