2-Chloroaniline → 6-Bromo-2-(2-chlorophenylamino)-3,4-difluorobenzoic acid

Temperatur

-78 °C

To a solution of i-Pr2NH (5.83 mL, 41.2 mmol) in THF (16 mL) at 0° C. was added n-BuLi (16.4 mL, 41.1 mmol, 2.5 M solution in hexanes). After stirring for 15 minutes, the reaction mixture was cooled to −78° C. 2-Chloroaniline (2.89 mL, 27.5 mmol) was added. After vigorous stirring for 10 minutes, a solution of 6-bromo-2,3,4-trifluorobenzoic acid (3.51 g, 13.8 mmol) in THF (4 mL) was added. The reaction mixture was warmed to room temperature and stirred for 2 hours at room temperature. The reaction mixture was concentrated, treated with 10% aqueous HCl (15 mL) until the aqueous phase was acidic, and extracted with EtOAc. The combined organic layers were dried over MgSO4, filtered, and concentrated in vacuo to give the crude material that was triturated three times with boiling CH2Cl2 to afford the desired product (3.18 g, 64%).

1. stirringAfter vigorous stirring for 10 minutes
2. temperatureThe reaction mixture was warmed to room temperature
3. stirringstirred for 2 hours at room temperature
4. concentrationThe reaction mixture was concentrated
5. additiontreated with 10% aqueous HCl (15 mL) until the aqueous phase
6. extractionextracted with EtOAc
7. dry with materialThe combined organic layers were dried over MgSO4
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customto give the crude material that
11. customwas triturated three times with boiling CH2Cl2

ORD-Eintrag

ord-82094c857e4847a5876d3c0617bac126

Quelldatensatz

uspto-grants-2009_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07485643B2