N-bromobutanimide → 1-(4-Bromo-1-methyl-1H-pyrrol-2-yl)-2,2,2-trichloro-1-ethanone

Under an ice cooling, N-methylpyrrole (8.10 g, 100 mmol) was dissolved in methylene chloride (100 ml), and trichloroacetyl chloride (20.00 g, 115 mmol) was added thereto. Thereafter, the mixture was stirred at a room temperature for 16 hours. A saturated sodium hydrogen carbonate aqueous solution was added to the mixture. The organic phase was collected by separation, washed with water, and dried over anhydrous magnesium sulfate. The solvent was distilled off. Thus, 2,2,2-trichloro-1-(methyl-1H-pyrrol-2-yl)ethanone (16.3 g, 72%) was obtained. The resulting 2,2,2-trichloro-1-(methyl-1H-pyrrol-2-yl)ethanone (15.0 g, 66.7 mmol) was dissolved in chloroform (150 ml), and N-bromosuccinimide (12.5 g, 70.2 mmol) was added thereto at a room temperature. The mixture was heated under reflux for 16 hours. After the mixture was allowed to cool, a saturated sodium hydrogen carbonate aqueous solution was added to the mixture. The organic phase was collected by separation, washed with water, and dried over anhydrous magnesium sulfate. The solvent was distilled off. The resulting residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:9) to give the title compound (14.0 g, 69%).

1. customat a room temperature
2. temperatureThe mixture was heated
3. temperatureunder reflux for 16 hours
4. temperatureto cool
5. customThe organic phase was collected by separation
6. washwashed with water
7. dry with materialdried over anhydrous magnesium sulfate
8. distillationThe solvent was distilled off
9. customThe resulting residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:9)

ORD record

ord-b0e2ca9a7a1a451299508675c04f9839

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09200008B2