[Cl:1][C:2]1[CH:8]=[CH:7][C:5]([NH2:6])=[CH:4][C:3]=1[O:9][CH3:10].[Br:11]N1C(=O)CCC1=O.[O-]S([O-])=O.[Na+].[Na+]>C(Cl)Cl>[Br:11][C:7]1[CH:8]=[C:2]([Cl:1])[C:3]([O:9][CH3:10])=[CH:4][C:5]=1[NH2:6]A solution of 4-chloro-3-methoxyaniline (1.0 equivalent) dissolved in CH2Cl2 (15 volumes) at 5° C. was treated portion wise with N-bromosuccinimide (1.03 equivalents), warmed to 20° C. and mixed for 5 minutes. A 5% aqueous Na2SO3 solution (10 volumes) was added and the mixture was stirred for 10 minutes. The layers were separated and the organic layer was washed with water and saturated brine, dried (Na2SO4), filtered and concentrated. The resulting solid was triturated with a minimal volume of heptane and the solid was collected by filtration and dried to constant mass (80% yield).
Wird geladen…