反应详情

To a solution of ethyl 1H-pyrrole-2-carboxylate (1.17 g) in carbon tetrachloride (40 ml), a solution of bromine (1.48 g) in carbon tetrachloride (80 ml) was added dropwise at −15° C., and the mixture was stirred for one hour. The mixture was warmed to a room temperature, and a 2-N sodium hydroxide aqueous solution (80 ml) was added thereto. The resulting mixture was subjected to extraction with ethyl acetate, and the organic layer was dried over anhydrous magnesium sulfate and concentrated under a reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:6) to give ethyl 4-bromo-1H-pyrrole-2-carboxylate (700 mg, 38%).

1. extractionThe resulting mixture was subjected to extraction with ethyl acetate
2. dry with materialthe organic layer was dried over anhydrous magnesium sulfate
3. concentrationconcentrated under a reduced pressure
4. customThe residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:6)