Molecular Formula | C7H3BrF2O2 |
Molar Mass | 237 |
Density | 1.872±0.06 g/cm3(Predicted) |
Boling Point | 285.0±40.0 °C(Predicted) |
pKa | 2.70±0.10(Predicted) |
Storage Condition | Sealed in dry,Room Temperature |
Introduction | 4-bromo-2, 5-difluorobenzoic acid is an organic intermediate, which can be prepared from 1, 4-dibromo-2, 5-difluorobenzene as raw material and 1, 4-dibromo-2, 5-difluorobenzene are prepared by reacting hydrogen with dry ice. |
Preparation | The solution of 1, 4-dibromo-2, 5-difluorobenzene (640mg,2.35mmol) in anhydrous ether (10mL) will be cooled in a dry ice-acetone bath is treated drop by drop with 2.5M n-butyl lithium/hexane (1.04mL,2.59mmol). The solution was stirred at -78°C for 30 minutes, and then treated with a piece of dry ice. After 5 minutes, remove the cooling bath and stir the mixture for another 30 minutes while warming to room temperature. Wash the mixture with EtOAc and water. The organic phase is separated and washed twice with saturated NaHCO3 aqueous solution. The combined organic phase was acidified with an aqueous solution of 1MHCl, extracted twice with DCM, dried and concentrated to give 4-bromo-2, 5-difluorobenzoic acid, which is a white solid. |