Hydrochloric Acid → 2-Methylphenyl boronic acid

Participants

Reaction Conditions

Reaction Steps

A solution of 2-bromotoluene (1.0 g) in dry tetrahydrofuran (50 ml) was cooled to -70° C. under an atmosphere of argon. A solution of tert-butyl lithium in pentane (1.7M, 7.6 ml) was added dropwise to the mixture whilst maintaining the temperature below -60° C. The reaction mixture was stirred at -70° C. for 0.5 hours. Trimethyl borate (0.73 ml) was added and the mixture allowed to warm to ambient temperature. The mixture was poured onto a mixture of aqueous 2M hydrochloric acid and ice, and the mixture extracted with ethyl acetate. The ethyl acetate extract was washed with brine, dried (MgSO4) and evaporated to give 2-methylphenylboronic acid as a white solid (0.48 g) which was used without further purification.

Provenance & Evidence