Triisopropyl borate → (4-Fluoro-2-methylphenyl)boronic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-bromo-4-fluoro-2-methylbenzene (5 g, 26.45 mmol) in THF (100 mL) was added n-butyllithium (12.7 mL) dropwise at −78° C. Tris(propan-2-yl)borate (10 g, 53.17 mmol) was added dropwise and the reaction was stirred overnight at −78° C. in a liquid nitrogen bath. The resulting solution was diluted with aqueous sodium hydroxide (1N, 30 mL) and extracted with ether (2×50 mL). The aqueous layers were combined and adjusted to pH 3 with HCl (3N), extracted with ethyl acetate (3×50 mL), and the organic layers were combined and concentrated in vacuo to give (4-fluoro-2-methylphenyl)boronic acid as a white solid (2.1 g, 52%).

Provenance & Evidence