Chloroform → 4-Bromo-2-fluoroanisole

Temperature

10 °C

Into a flask of 5 l were charged 384 g (3.04 mol) of 2-fluoroanisole and 2.5 l of chloroform, to which was added dropwise 504 g (3.16 mol) of bromine over about 3 hours while cooling on an ice water bath at 10° C. The resulting mixture was stirred at room temperature over a night and heated under reflux for 8 hours. After the air cooling, the product was added with 1 l of water and 50 g of sodium bisulfite and sufficiently shaken to separate into two layers. The resulting organic layer was washed with an aqueous solution of 5% sodium hydrogen carbonate and further with 1 l of water and dried on magnesium sulfate. After magnesium sulfate was filtered off, the filtrate was concentrated and distilled under a reduced pressure (4 mmHg, bp: 93-°96° C.) to obtain 585 g (yield: 94%) of 3-fluoro-4-methoxybromobenzene.

1. temperatureheated
2. temperatureunder reflux for 8 hours
3. temperatureAfter the air cooling
4. stirringsufficiently shaken
5. customto separate into two layers
6. washThe resulting organic layer was washed with an aqueous solution of 5% sodium hydrogen carbonate and further with 1 l of water
7. customdried on magnesium sulfate
8. filtrationAfter magnesium sulfate was filtered off
9. concentrationthe filtrate was concentrated
10. distillationdistilled under a reduced pressure (4 mmHg, bp: 93-°96° C.)

ORD record

ord-b3562b5f82ae42299feec8bea0368ff5

Source dataset

uspto-grants-1992_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05098602