Sulfuric Acid → 4-Bromo-3-(trifluoromethyl)phenol

Temperature

0 °C

4-Bromo-3-trifluoromethylaniline (48 g, 0.2 mol) was treated with water (300 ml) and concentrated H2SO4 (36 ml) at 60° C. for 1 hour. The resulting suspension was cooled in an ice bath and treated with sodium nitrite (16 g, 0.23 mol) in water (30 ml) maintaining the temperature of the reaction mixture below 10° C. The resulting solution was stirred at 0° C. for 1 hour, and then added portionwise, over 1 hour, to a 25% H2SO4 aqueous solution (160 ml) whilst steam distilling. After collecting approximately 1 liter of distillate, the aqueous distillate was extracted with ether and the organic solution dried using MgSO4, filtered and concentrated. The product, 4-bromo-3-trifluoromethylphenol, was obtained by distillation under reduced pressure. Yield 18.0 g (37%); boiling point 68-71/1 mmHg.

1. temperatureThe resulting suspension was cooled in an ice bath
2. temperaturemaintaining the temperature of the reaction mixture below 10° C
3. distillationdistilling
4. distillationAfter collecting approximately 1 liter of distillate
5. extractionthe aqueous distillate was extracted with ether
6. customthe organic solution dried
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-6a1bd8a00faa462fbf15b455dc582202

Source dataset

uspto-grants-1998_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05707995