Boron tribromide → 2-(2,6-Difluorophenyl)phenol

Treatment of 2,6-difluorobromobenzene (8.9 g, 46.1 mmol) with 2-methoxybenzeneboronic acid (10.51 g, 69.2 mmol), dichlorobis(tri-o-tolylphosphine)-palladium(II) (1.81 g, 2.3 mmol), and potassium carbonate (15.9 g, 115.3 mmol) generally according to the procedure described for Intermediate 37 provided 4.6 g (45%) of 2′,6′-difluoro-1,1′-biphenyl-2-yl methyl ether. To a solution of 2′,6′-difluoro-1,1′-biphenyl-2-yl methyl ether (4.5 g, 20.4 mmol) in dichloromethane (100 mL) cooled to −78° C. was added boron tribromide (5.11 g, 1.0 M in dichloromethane) and the reaction mixture was allowed to stir for 30 min. The reaction mixture was allowed to warn to room temperature and was quenched by the addition of ice (150 mL). The organic layer was separated and the aqueous layer was extracted with dichloromethane (500 mL). The combined organic layers were washed with water (400 mL), saturated aqueous sodium chloride (100 mL), dried (magnesium sulfate), and the solvent removed in vacuo to provide a crude oil. Purification by flash column chromatography (silica, hexanes:ethyl acetate 95:5) provided 3.95 g (94%) of 2′,6′-difluoro-1,1′-biphenyl-2-ol as a colorless oil. Anal. calcd. for C12H8F2O: C, 69.9; H, 3.91. Found: C, 68.51; H, 4.06.

1. customto warn to room temperature
2. customwas quenched by the addition of ice (150 mL)
3. customThe organic layer was separated
4. extractionthe aqueous layer was extracted with dichloromethane (500 mL)
5. washThe combined organic layers were washed with water (400 mL), saturated aqueous sodium chloride (100 mL)
6. dry with materialdried (magnesium sulfate)
7. customthe solvent removed in vacuo
8. customto provide a crude oil
9. customPurification by flash column chromatography (silica, hexanes:ethyl acetate 95:5)

ORD record

ord-b9b59048fc274c81a60015da45f47f2f

Source dataset

uspto-grants-2008_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07435837B2