Carbon Dioxide → 2-Bromo-5-(trifluoromethyl)benzoic acid

Temperature

-78 °C

To a solution of n-BuLi (26.7 mL of 2.5M solution in tetrahydrofuran (THF), 66.7 mmol) in THF (130 mL) at −78° C. was added 2,2,6,6-tetramethylpiperidine (22.5 mL, 133.4 mmol). The mixture was stirred at −78° C. for 30 minutes and then carefully lowered to −100° C. using liquid nitrogen. Neat 1-bromo-4-(trifluoromethyl)benzene (15 g, 66.7 mmol) was added. The mixture was kept at −100° C. for 6 hours and poured onto freshly crushed dry ice. The resulting mixture was stirred at room temperature for 16 hours. The residue solvent was removed by evaporation. Water (150 mL) was added and the mixture was extracted with diethyl ether (3×50 mL). The aqueous layer was acidified using concentrated hydrochloric acid (HCl), extracted with methylene chloride (3×50 mL). The combined organic layers were washed with saturated sodium chloride (NaCl) (75 ml), dried with magnesium sulfate (MgSO4), filtered and concentrated to yield the title compound as a white solid (5.41 g). 1H NMR (400 MHz, CDCl3) δ 7.7 (dd, J=8.4, 2.3 Hz, 1 H) 7.9 (d, J=8.4 Hz, 1 H) 8.3 (d, J=2.0 Hz, 1 H). MS (ES+) Calc: 267.93, Found: 266.7 (M−1).

1. customcarefully lowered to −100° C.
2. waitThe mixture was kept at −100° C. for 6 hours
3. stirringThe resulting mixture was stirred at room temperature for 16 hours
4. customThe residue solvent was removed by evaporation
5. additionWater (150 mL) was added
6. extractionthe mixture was extracted with diethyl ether (3×50 mL)
7. extractionextracted with methylene chloride (3×50 mL)
8. washThe combined organic layers were washed with saturated sodium chloride (NaCl) (75 ml)
9. dry with materialdried with magnesium sulfate (MgSO4)
10. filtrationfiltered
11. concentrationconcentrated

ORD record

ord-1d18ec4095dc40bd9ab8ef2e626e4ed3

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08383660B2