Hydrochloric Acid → 2-[4-(Trifluoromethoxy)phenyl]ethanol

Temperature

-50 °C

A Grignard reagent prepared from 4-trifluoromethoxybromobenzene (54 g, 220 mmol) and dried Mg (5.4 g, 220 mmol) in 250 ml ether solvent was cooled down to -50° C., followed by gradually dropwise adding thereto ethylene oxide (29.3 g, 670 mmol), gradually heating the resulting reaction mixture up to room temperature, further stirring it for one hour at room temperature, adding the reaction solution to 6N HCl (300 ml), extracting the resulting product with ethyl acetate, washing the extraction solution successively with a saturated aqueous solution of sodium bicarbonate and water, drying over magnesium sulfate, distilling off the solvent, distilling the residue under reduced pressure by means of a Vigoureaux tube, to isolate a colorless liquid, 2-(4-trifluoromethoxyphenyl)ethanol (14.5 g, 70.3 mmol) having a b.p. of 82° to 84° C. under 3.5 Torr, adding to this liquid, xylene (60 ml) and HBr aqueous solution (47%) (60 ml), refluxing the mixture for 9 hours, adding water to the reaction mixture, extracting the resulting product with toluene, washing the reaction solution successively with a saturated aqueous solution of sodium bicarbonate and water, drying the resulting organic layer over magnesium sulfate, distilling off the solvent, distilling the residue under reduced pressure using Vigoureux tube, to isolate a colorless liquid, 2-(4-trifluoromethoxyphenyl)bromoethane (12.0 g, 51.9 mmol) having a b.p. of 75° C. under 4 Torr. The yield of this product from 4-trifluoromethoxybromobenzene was 23.6%.

1. additionby gradually dropwise adding
2. customthe resulting reaction mixture up to room temperature
3. extractionextracting the resulting product with ethyl acetate
4. washwashing the extraction solution successively with a saturated aqueous solution of sodium bicarbonate and water
5. dry with materialdrying over magnesium sulfate
6. distillationdistilling off the solvent
7. distillationdistilling the residue under reduced pressure by means of a Vigoureaux tube

ORD record

ord-640782266f294b508ba33073ee8b7e69

Source dataset

uspto-grants-1997_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05702641