Hydrochloric Acid → (3-Methoxyphenyl)boronic acid

Participants

Reaction Steps

n-Butyllithium in n-hexane (925.0 mL, 1.59 M) was added dropwise to a mixture of THF (1,000 mL) and 1-bromo-3-methoxybenzene (T-1) (250.0 g, 1.34 mol) at −70° C. under an atmosphere of nitrogen. After the addition had been completed, the reaction mixture was stirred at the same temperature for 1 hour. Triisopropyl borate (300.9 g, 1.60 mol) was added dropwise, and then the mixture was warmed slowly to room temperature. The stirring was continued at room temperature for 18 hours, and the reaction mixture was poured into 6M-hydrochloric acid. The mixture was extracted with ethyl acetate (500 mL) four times, and the organic layer was washed with water. After the organic layer had been dried over anhydrous magnesium sulfate, the organic solvent was distilled off under reduced pressure. The residue was sufficiently washed with heptane to leave colorless solids (156.1 g) of 3-methoxyphenylboronic acid (T-2).

Provenance & Evidence