反应详情

N-Bromosuccinimide (5.86 g, 0.033 mol) was added to a solution of ethyl 5-ethyl-1H-pyrrole-2-carboxylate (Intermediate 12, 5.0 g, 0.03 mol) in DCM (85 ml) at 0° C., and the reaction was stirred for 30 minutes then poured to a chilled beaker containing 2 N NaOH (50 ml). The layers were separated and the aqueous layer was extracted with DCM (×3). The combined organic extracts were washed with water and brine, dried over magnesium sulfate and concentrated. The resultant dark brown solid was purified by flash chromatography (hexanes/EtOAc, 10:1) to give the title product as a white solid (5.0 g, 68%).

1. additionthen poured to a chilled beaker
2. customThe layers were separated
3. extractionthe aqueous layer was extracted with DCM (×3)
4. washThe combined organic extracts were washed with water and brine
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated
7. customThe resultant dark brown solid was purified by flash chromatography (hexanes/EtOAc, 10:1)