Carbon Dioxide → 3-Chloro-2-fluoro-6-(trifluoromethyl)benzoic acid

Temperature

-78 °C

77.0 g of 3-fluoro-4-chlorobenzotrifluoride was dissolved in 750 ml of dried tetrahydrofuran, and to the solution, 250 ml of hexane solution of n-butyl lithium (1.6 mol/l) was added dropwise over 15 minutes at -78° C. under a nitrogen atmosphere. After stirring the solution at -78° C. for 2 hours. 50 g of dry ice was gradually added to the solution at the same temperature. After elevating the temperature of the solution up to room temperature, 500 ml of ice water was added to the solution to separate the resulting solution. While cooling down the aqueous layer, the layer was adjusted to a pH value of 1 with concentrated hydrochloric acid. The aqueous layer was then extracted with ether, washed with water and dried over anhydrous magnesium sulfate. The solvent was distilled under reduced pressure, and the oily residue obtained was crystalized with n-hexane, followed by a filtration and then dried to obtain 88.4 g of the title compound(mp. 92-93° C.).

1. additionwas added to the solution
2. customto separate the resulting solution
3. temperatureWhile cooling down the aqueous layer
4. extractionThe aqueous layer was then extracted with ether
5. washwashed with water
6. dry with materialdried over anhydrous magnesium sulfate
7. distillationThe solvent was distilled under reduced pressure
8. customthe oily residue obtained
9. customwas crystalized with n-hexane
10. filtrationfollowed by a filtration
11. customdried

ORD record

ord-8b85ed6de7204fdd82bd1c047d044d6c

Source dataset

uspto-grants-2000_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06054605