Hydrochloric Acid → 6-Bromo-7-methyl-1H-indole-2,3-dione

Temperature

80 °C

Chloral alcoholate (0.43 g, 1.05 eq) and Na2SO4 (2.84 g, 20 mmol) were dissolved in 10 mL water. 3-Bromo-2-methylaniline (0.33 g, 1.77 mmol) was added to the solution followed by 0.16 mL conc. HCl aqueous solution and NH2OH.HCl (0.38 g, 3.0 eq). The mixture was refluxed for 15 min and stirring was continued for additional 1 hr at RT. The precipitate was collected by filtration, washed with water and dried under vacuum. This precipitate was dissolved in 1 mL H2SO4 and the solution was heated (80° C.) for 15 min. After cooling down to RT, the mixture was poured into ice-water mixture and the precipitate was collected, washed with water and dried under vacuum to give the title compound (0.26 g, 61%).

1. temperatureThe mixture was refluxed for 15 min
2. filtrationThe precipitate was collected by filtration
3. washwashed with water
4. customdried under vacuum
5. dissolutionThis precipitate was dissolved in 1 mL H2SO4
6. temperatureAfter cooling down to RT
7. additionthe mixture was poured into ice-water mixture
8. customthe precipitate was collected
9. washwashed with water
10. customdried under vacuum

ORD record

ord-3f5947e437ae4c5fb6eecf5ec9953d21

Source dataset

uspto-grants-2013_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08470782B2