Hydrochloric Acid → 4-Bromo-3-chloro-3,4,4-trifluorobutan-1-ol

Temperature

5 °C

A solution of sodium hydrosulfite (34.8 g, 0.2 mol) and sodium bicarbonate (22.0 g, 0.262 mol) in water (400 mL) was treated with 400 mL of THF and the mixture was cooled to 5° C. A mixture of 1,2-dibromo-1-chlorotrifluoroethane (VI) (55.26 g, 0.2 mol) and ethyl vinyl ether (21.6 g, 0.3 mol) was added in one portion to the above mixture with stirring and cooling. The mixture was then stirred at 10°-15° C. for 30 min and then solid sodium chloride was added to saturate the aqueous layer. The aqueous layer was separated and extracted with THF (100 mL). The combined THF extract was diluted with water (100 mL) and treated with sodium borohydride (7.57 g, 0.2 mol) in portions with stirring and cooling (ice-water bath). The mixture was stiffed for 30 min and then acidified 3N HCl by dropwise addition. The aqueous layer was saturated with sodium chloride and the organic layer was separated, washed with brine and dried over anhydrous magnesium sulfate. The residue obtained after evaporation of the solvent was distilled under vacuum to give 37.7 g (78%) of the desired alcohol as a clear oil, bp 98°-100° C./40 mmHg.

1. additionwas added in one portion to the above mixture
2. temperaturecooling
3. stirringThe mixture was then stirred at 10°-15° C. for 30 min
4. concentrationto saturate the aqueous layer
5. customThe aqueous layer was separated
6. extractionextracted with THF (100 mL)
7. extractionThe combined THF extract
8. additionwas diluted with water (100 mL)
9. stirringwith stirring
10. additionby dropwise addition
11. customthe organic layer was separated
12. washwashed with brine
13. dry with materialdried over anhydrous magnesium sulfate
14. customThe residue obtained
15. customafter evaporation of the solvent
16. distillationwas distilled under vacuum

ORD record

ord-afa2a16797554bbb8ee3823427bd1f49

Source dataset

uspto-grants-1997_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05627174