[F:1][C:2]1[CH:3]=[C:4]([OH:10])[CH:5]=[CH:6][C:7]=1[O:8][CH3:9].[Br:11]Br.O.S([O-])([O-])=O.[Na+].[Na+]>ClCCl>[Br:11][C:5]1[CH:6]=[C:7]([O:8][CH3:9])[C:2]([F:1])=[CH:3][C:4]=1[OH:10]3-Fluoro-4-methoxy-phenol (21.32 g; 0.15 mol) prepared according to literature [Freedman, J.; Stewart, K. T.; J. Heterocycl. Chem. 1989, 26, 1547-1554] is dissolved in dry dichloromethane (300 mL). The well stirred reaction mixture is cooled to −15° C. (ice/salt). A solution of bromine (23.97 g; 0.15 mol) in dry dichloromethane (75 mL) is dropped into the reaction mixture. After complete addition stirring is continued for one hour. Water (150 mL) containing sodium sulfite (3.0 g) is added to the reaction mixture. Stirring is continued at ambient temperature for 30 min. The organic layer is separated, ished with water (100 mL) and dried over MgSO4 in the presence of decolorizing charcoal. After filtration the solvent is completely removed under reduced pressure. The residue is crystallized from tert-butylmethylether/hexane to yield the title compound as a colorless solid.
Wird geladen…
