1-(4-Bromo-1-methyl-1H-pyrrol-2-yl)-2,2,2-trichloro-1-ethanone → Ethyl 4-bromo-1-methyl-1H-pyrrole-2-carboxylate

In ethanol (100 ml), 1-(4-bromo-1-methyl-1H-pyrrol-2-yl)-2,2,2-trichloroethanone (12.1 g, 40 mmol) prepared in the Step 10-1-1 was dissolved, and under an ice cooling a 20% sodium ethoxide-ethanol solution was added thereto. Thereafter, the mixture was heated under reflux for 3 hours. After the mixture was allowed to cool, the solvent was distilled off, and 3.5% hydrochloric acid (100 ml) and chloroform (150 ml) was added to the mixture. The organic phase was collected by separation, washed with a saturated sodium hydrogen carbonate aqueous solution and water in order, and dried over anhydrous magnesium sulfate. The solvent was distilled off, and the resulting residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:5) to give the title compound (7.39 g, 80%).

1. dissolutionwas dissolved
2. temperatureThereafter, the mixture was heated
3. temperatureunder reflux for 3 hours
4. temperatureto cool
5. distillationthe solvent was distilled off
6. addition3.5% hydrochloric acid (100 ml) and chloroform (150 ml) was added to the mixture
7. customThe organic phase was collected by separation
8. washwashed with a saturated sodium hydrogen carbonate aqueous solution and water in order
9. dry with materialdried over anhydrous magnesium sulfate
10. distillationThe solvent was distilled off
11. customthe resulting residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:5)

ORD record

ord-652c1095f4554c6095f158b2448bc7e0

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09200008B2