Sulfuric Acid → 5-Bromo-2-tert-butylphenol

Participants

Reaction Steps

To a solution of 29.5 g (170.3 mmol) of 3-bromophenol in 100 mL of carbon tetrachloride (under a blanket of argon) was added 16.4 g (221.3 mmol) of 2-methyl-2-propanol followed by 20 mL of conc. sulfuric acid. The reaction mixture was allowed to stir at ambient temperature for 3.5 days. The clear, colorless solution turned pink and eventually turned purple in color. The reaction mixture was neutralized with sat. NaHCO3 (aq.) solution and then extracted between water and dichloromethane. The layers were separated and the aqueous phase was washed with dichloromethane. The organic phases were combined and washed with brine, dried over MgSO4, filtered and concentrated in vacuo to a purple oil. Purification by flash chromatography (silica, 5% ethyl acetate in hexane) followed by kugelrohr distillation (85-95° C., 2 mm Hg) gave the title compound as a clear, slightly yellow oil. PMR (CDCl3): δ 1.38 (9 H, s), 4.93 (1 H, s), 6.84 (1 H, d, J=2.1 Hz), 6.99 (1 H, dd, J=2.1, 8.2 Hz), 7.12 (1 H, d, J=8.2 Hz).

Provenance & Evidence