反应详情

To a stirring solution of 2-cyclopentyl phenol (7.9 g, 48.7 mmol) in acetic acid (32 mL) and water (16 mL) was added HBr (33% in AcOH, 50.45 mL, 292.2 mmol) followed by the dropwise addition of DMSO (34.8 g, 31.6 mL, 445.0 mmol) over 10 min. The reaction was quenched with saturated aqueous NaHCO3 and concentrated in vacuo to remove gasses. The residue was brought up in ether (200 mL), washed with water (2×100 mL) and brine (100 mL) then dried over Na2SO4. The solution was filtered and concentrated in vacuo to produce an oil which was purified by silica gel chromatography (0-10% ethyl acetate/hexane) to provide 4-bromo-2-cyclopentylphenol (10.5 g, 89% yield) as a colorless oil. 1H NMR (400.0 MHz, DMSO-d6) δ 9.59 (s, 1H), 7.20 (d, J=2.5 Hz, 1H), 7.13 (dd, J=2.5, 8.5 Hz, 1H), 6.73 (d, J=8.5 Hz, 1H), 3.21-3.13 (m, 1H), 1.95-1.88 (m, 2H), 1.77-1.69 (m, 2H), 1.65-1.44 (m, 4H).

1. customThe reaction was quenched with saturated aqueous NaHCO3
2. concentrationconcentrated in vacuo
3. customto remove gasses
4. washwashed with water (2×100 mL) and brine (100 mL)
5. dry with materialthen dried over Na2SO4
6. filtrationThe solution was filtered
7. concentrationconcentrated in vacuo
8. customto produce an oil which
9. customwas purified by silica gel chromatography (0-10% ethyl acetate/hexane)