Trimethyl borate → 4-Fluoro-3-(hydroxymethyl)benzeneboronic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-bromo-2-fluoro-benzyl alcohol (10 g, 49 mmol) in TBF (500 mL) at −78° C. was added BuLi (2.5M, 43 mL, 107 mmol) dropwise keeping the internal temperature below −73° C. After 25 min., trimethylborate (25 mL, 107 mmol) was added and the resulting reaction mixture stirred for 15 h at −78° C., 1 h at 21° C., then diluted with HCl 10% and ethyl acetate. The organic extracts were washed (H2O, brine), dried (MgSO4), filtered and concentrated. The residue was solidified from hexane/ethyl acetate with water (5 drops) to afford the 4-fluoro-3-hydroxymethyl-benzene-boronic acid compound as a white solid.

Provenance & Evidence