Sulfuric Acid → 5-Bromo-2-nitrophenol

Participants

Reaction Conditions

Reaction Steps

To a solution of concentrated sulfuric acid (32.6 mL) in water (105 mL) was added potassium nitrate (51.5 g, 509 mmol) at 10° C. The reaction mixture was stirred for 5 min before adding 3-bromophenol (49.35 g, 285 mmol) dropwise so that the temperature of the reaction was maintained around 10° C. The reaction mixture was stirred at ambient temperature for an additional 2 h, diluted with water (350 mL) and extracted with diethyl ether. The organic layer was washed with brine, dried over sodium sulfate and concentrated in vacuo. The crude material was purified by flash column chromatography (SiO2, 19:1 hexanes/ethyl acetate) to give 5-bromo-2-nitrophenol (11.3 g, 18%) as a yellow-green solid: 1H NMR (DMSO-d6, 300 MHz) δ 11.44 (s, 1H), 7.84 (d, J=8.7 Hz, 1H), 7.33 (d, J=2.1 Hz, 1H), 7.18 (dd, J=8.7, 2.1 Hz, 1H).

Provenance & Evidence