Triisopropyl borate → (2-Phenylthiophen-3-yl)boronic acid

Participants

Reaction Conditions

Reaction Steps

To a mixture of 3-bromo-2-phenylthiophene (1.99 g, 8.32 mmol) and B(Oi-Pr)3 (1.81 mL, 12.5 mmol) in THF (20 mL) was added n-BuLi (1.65 M in hexane, 10.1 mL, 16.6 mmol) at −78° C. The mixture was stirred at −78° C. for 30 min and at 0° C. for 30 min. The mixture was diluted with 1 M HCl aqueous solution at 0° C., extracted with EtOAc, washed with brine, dried over Na2SO4, filtered, concentrated in vacuo and purified by column chromatography on silica gel (hexane/EtOAc=90/10 to 0/100) to yield the title compound (87.4 mg, 5% yield) as a white solid: 1H NMR (DMSO-d6, 300 MHz): δ ppm 7.19 (1H, d, J=4.9 Hz), 7.27-7.44 (3H, m), 7.46-7.58 (3H, m), 8.06 (2H, s).

Provenance & Evidence