Hydrochloric Acid → 3-Tolylboronic acid

Participants

Reaction Conditions

Reaction Steps

n-Butyllithium (15 mL, 2.5M in hexane, 37.4 mmol) was added dropwise to a solution of 3-bromotoluene (5.8 g, 34.0 mmol) in 50 mL of THF cooled to -78° C. The resulting suspension was stirred at -78° C. for 30 min, treated with trimethyl borate (10.6 g, 102.2 mmol), stirred -78° C. for 10 min, and allowed to warm to room temperature. The reaction mixture was stirred at room temperature for 16 hours, then cooled in an ice bath and acidified to pH 6 with 2N HCl. The mixture was extracted with methylene chloride, and the organic extract was washed with bdne, dried over Na2SO4, and concentrated to yield 4.24 g of 3-methylphenyl boronic acid.

Provenance & Evidence