Bromine → 4-Bromo-2,6-difluoroaniline

Temperature

10 °C

507.5 g of 2,6-difluoroaniline are added to 2500 ml of acetic acid, the mixture is cooled to 10° C., and a solution of 195 ml of bromine in 250 ml of acetic acid is added dropwise at 10-15° C. over the course of 3 hours. The mixture is subsequently stirred at room temperature for a further 1 hour and poured into 5000 ml of ice-water, the precipitated crystals are filtered off with suction and washed a number of times with a total of 3000 ml of ice-water, and the crystals are dried over Al2O3 under reduced pressure, giving 4-bromo-2,6-difluoroaniline, yield 91.7%, GC 99.6%.

1. filtrationthe precipitated crystals are filtered off with suction
2. washwashed a number of times with a total of 3000 ml of ice-water
3. customthe crystals are dried over Al2O3 under reduced pressure

ORD record

ord-cc6b385e0f6746c092e513de05a175bf

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06716491B2