Carbon Dioxide → 3-Bromo-2-fluorobenzoic acid

Temperature

-10 °C

To a stirred solution of 2,2,6,6-tetramethylpiperidine (31.1 g, 0.22 mol) in THF (200 mL) was added dropwise a solution of butyl lithium (0.22 mol) in hexane (146.7 mL) at −10° C. The mixture was stirred for 1.5 h at −10° C. and the fluoroarene (1-bromo-2-fluorobenzene) in THF (100 mL) was consecutively added to the solution at −75° C. The mixture was stirred for 2 h at −75° C., before being poured on excess of CO2 gas. Then the reaction mixture was warmed to room temperature and stirred over night. After evaporation of the solvent, the residue was dissolved in water (150 mL), washed with diethyl ether (2×50 mL), acidified (to pH 1) and the solid was filtered off and dried under vacuum to give 24.3 g of the title compound as a white solid (yield: 55%).

1. stirringThe mixture was stirred for 2 h at −75° C.
2. temperatureThen the reaction mixture was warmed to room temperature
3. stirringstirred over night
4. customAfter evaporation of the solvent
5. dissolutionthe residue was dissolved in water (150 mL)
6. washwashed with diethyl ether (2×50 mL)
7. filtrationthe solid was filtered off
8. customdried under vacuum

ORD record

ord-76db9f8c6d66422ba92ba33edbabc21a

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08084449B2