Tetra-n-butylammonium tribromide → 4-Bromo-2-ethyl-6-fluorophenol

A solution of tetrabutyl ammonium tribromide (4.2 g, 8.6 mmol) in CHCl3 (25 mL) was added to a stirred solution of 2-ethyl-6-fluoro-phenol (1.1 g, 7.9 mmol) dissolved in CHCl3 (25 mL). The reaction mixture was stirred for 24 hrs and then quenched with 5% solution of sodium thiosulfate (30 mL). The biphasic mixture was stirred for 30 mins and then the layers were separated. The organic layer was washed with 1N HCl, saturated NaHCO3, brine, dried over Na2SO4 and concentrated. The crude residue was purified by flash column chromatography (0–10% EtOAc in hexanes) to give the desired product (1 g, 60%). 1H NMR (400 MHz, CDCl3): δ 1.21 (t, J=7.6 Hz, 3 H), 2.65 (q, J=7.6 Hz, 2 H), 5.09 (d, J=4.8 Hz, 1 H), 7.06 (s, 1 H), 7.09 (d, J=11.9 Hz, 1 H).

1. customquenched with 5% solution of sodium thiosulfate (30 mL)
2. stirringThe biphasic mixture was stirred for 30 mins
3. customthe layers were separated
4. washThe organic layer was washed with 1N HCl, saturated NaHCO3, brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated
7. customThe crude residue was purified by flash column chromatography (0–10% EtOAc in hexanes)

ORD record

ord-a085a84b8088407ab7e6903044f6e125

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07148226B2