[F:1][CH:2]([F:14])[C:3]([C:5]1[CH:10]=[CH:9][C:8]([O:11]C)=[CH:7][C:6]=1[F:13])=[O:4].B(Br)(Br)Br>C(Cl)Cl>[F:14][CH:2]([F:1])[C:3]([C:5]1[CH:10]=[CH:9][C:8]([OH:11])=[CH:7][C:6]=1[F:13])=[O:4]To 2,2-difluoro-1-(2-fluoro-4-methoxyphenyl)ethanone (45.0 g, 0.22 mol) in 400 mL of CH2Cl2 at −78° C. was added BBr3 (165.67 g, 0.66 mol) in 100 mL of CH2Cl2 dropwise. The resulting solution was stirred overnight at 25° C., and was quenched by dropwise addition of CH3OH (900 mL) at −30° C. and after stirring for 2 hours at −30° C. and for 1 hour at 25° C., the solvents were evaporated and the residue was purified by column chromatography (PE/EA 6:1) to afford 2,2-difluoro-1-(2-fluoro-4-hydroxyphenyl)ethanone as a solid.
Wird geladen…