p-Toluenesulfonic acid monohydrate → 5-Bromo-1-methyl-2-phenyl-1H-benzo[d]imidazole

7.8 g (26 mmol) of 4′-bromo-N-methyl-2′-aminobenzanilide was suspended in 50 mL of xylene. After the addition of 1.5 g (7.7 mmol) of p-toluenesulfonic acid monohydrate, the mixture was heat refluxed for 7 hours. After completion of the reaction, the mixture was filtered. The resulting solid was dissolved in methylene chloride, washed with a 10% potassium carbonate aqueous solution and a saturated sodium chloride solution, and dried over magnesium sulfate. The solvent was then evaporated under reduced pressure. An organic substance was also collected from the filtrate by the same washing method. The solid and the organic substance were purified by silica gel column chromatography to obtain 6.5 g of 5-bromo-1-methyl-2-phenyl-1H-benzimidazole as a white crystal (yield: 89%).

1. temperaturethe mixture was heat
2. temperaturerefluxed for 7 hours
3. customAfter completion of the reaction
4. filtrationthe mixture was filtered
5. dissolutionThe resulting solid was dissolved in methylene chloride
6. washwashed with a 10% potassium carbonate aqueous solution
7. dry with materiala saturated sodium chloride solution, and dried over magnesium sulfate
8. customThe solvent was then evaporated under reduced pressure
9. customAn organic substance was also collected from the filtrate by the
10. washsame washing method
11. customThe solid and the organic substance were purified by silica gel column chromatography

ORD record

ord-ed9fbd6b3b4b433a8cba6f92e0fe9e41

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08803420B2