Carbon Dioxide → 5-Bromo-2,3,4-trifluorobenzoic acid

Temperatur

-78 °C

To a solution of 1-bromo-2,3,4-trifluorobenzene (1) (5.0 mL, 41.7 mmol) in THF (120 mL) was added lithium diisopropylamine (2.0 M solution, 21 mL, 42 mmol) at −78° C. After stirring for 1 hour at −78° C., the mixture was added to a solution of CO2 in THF (1 L). The dry-ice bath was removed and the reaction mixture stirred overnight at room temperature. The reaction mixture was quenched with 10% aqueous HCl (835 mL), concentrated, and washed with ether (250 mL). The combined organics were washed with 5% aqueous NaOH (300 mL) and water (100 mL, pH 12). The aqueous layer was acidified (pH 0) with concentrated HCl. The resulting suspension was extracted with ether (2×300 mL), dried over MgSO4, filtered, concentrated under reduced pressure to afford 7.70 g (72% yield) of the desired product (2).

1. customThe dry-ice bath was removed
2. stirringthe reaction mixture stirred overnight at room temperature
3. customThe reaction mixture was quenched with 10% aqueous HCl (835 mL)
4. concentrationconcentrated
5. washwashed with ether (250 mL)
6. washThe combined organics were washed with 5% aqueous NaOH (300 mL) and water (100 mL, pH 12)
7. extractionThe resulting suspension was extracted with ether (2×300 mL)
8. dry with materialdried over MgSO4
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure

ORD-Eintrag

ord-93342c594d724692a8d7bba574c78ddf

Quelldatensatz

uspto-grants-2007_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07271178B2