Hexachloroethane → 2-Chloro-3-fluorobenzoic acid

Temperature

-90 °C

A solution of 3-fluorobenzoic acid (8.0 g, 64.3 mmol) in 40 mL of THF was added dropwise to a solution of sec-butyllithium (90 mL, 128.6 mmol) and N,N,N′,N′-tetramethylethylenediamine (20.0 mL, 147.9 mmol) in THF (100 mL) at −90° C. After addition, the reaction mixture was stirred at −90° C. for 30 minutes. Hexachloroethane (54 g, 257.2 mmol) in THF (100 mL) was added to reaction mixture dropwise. Then the reaction mixture was stirred at −78° C. to room temperature for 16 hours. The solvent was evaporated and the water was added to the residue. The reaction mixture was acidifed to PH=1 by added conc. hydrochloric acid. Then the reaction mixture was extracted with ether (3×). The combined organic phase was dried and conc. The crude product was washed with hexane for 3 times. Then it was filtered to get pure product (9.2 g, 93%). EI-MS m/z 172.89 (M−).

1. additionAfter addition
2. stirringThen the reaction mixture was stirred at −78° C. to room temperature for 16 hours
3. customThe solvent was evaporated
4. additionthe water was added to the residue
5. additionby added conc. hydrochloric acid
6. extractionThen the reaction mixture was extracted with ether (3×)
7. customThe combined organic phase was dried
8. washconc. The crude product was washed with hexane for 3 times
9. filtrationThen it was filtered

ORD record

ord-bf7a77e998c242509cd4b52ae0e914b7

Source dataset

uspto-grants-2004_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06680317B2