Ethanol → Ethyl 4-bromopyrrole-2-carboxylate

Temperature

25 °C

1H-Pyrrole-2-carboxylic acid ethyl ester (10 g) was dissolved in carbon tetrachloride (50 ml). A carbon tetrachloride solution (50 ml) of bromine was added dropwise thereto on ice over 30 minutes. The reaction mixture was stirred at 25° C. for one hour. The suspension of reaction mixture was added dropwise to an ethanol solution (100 ml) of 10% sodium ethoxide on ice over 20 minutes. The solvent was concentrated under reduced pressure. The resulting residue was diluted with ethyl acetate (40 ml) and water (20 ml). The organic layer was washed with an aqueous solution saturated with sodium chloride (10 ml), and then concentrated. The residue obtained by concentration under reduced pressure was purified by silica gel column chromatography (hexane/ethyl acetate). Thus, a brown solid was obtained (10 g, 99%).

1. additionThe suspension of reaction mixture
2. concentrationThe solvent was concentrated under reduced pressure
3. additionThe resulting residue was diluted with ethyl acetate (40 ml) and water (20 ml)
4. washThe organic layer was washed with an aqueous solution saturated with sodium chloride (10 ml)
5. concentrationconcentrated
6. customThe residue obtained by concentration under reduced pressure
7. customwas purified by silica gel column chromatography (hexane/ethyl acetate)
8. customThus, a brown solid was obtained (10 g, 99%)

ORD record

ord-e99c2722ad274979a1d814b158aade69

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09102692B2