Trimethyl borate → (4-Fluoro-5-isopropyl-2-methoxyphenyl)boronic acid

To a solution of 1-fluoro-4-iodo-2-isopropyl-5-methoxybenzene (2.61 g, 8.88 mmol) in THF at −78° C., n-butyl lithium (2.5 M, 4.26 mL, 10.65 mmol) was added dropwise. The solution was stirred at −78° C. for 30 min. Trimethyl borate (2.98 mL, 26.6 mmol) was added. The solution was then stirred at −78° C. for 3 h. The reaction was quenched at −78° C. with saturated NH4Cl and the mixture was warmed to room temperature. The organic was extracted with EtOAc (3×50 mL). The combined EtOAc layers were washed with brine and dried over Na2SO4. The title compound was obtained as a solid pure enough for next step. Further purification with silica gel caused decomposition of product. 1H NMR (CDCl3, 500 MHz) δ 7.74 (d, J=10.0 Hz, 1H), 6.62 (d, J=12.5 Hz, 1H), 5.65 (br s, 2H), 3.92 (s, 3H), 3.20 (m, 1H), 1.22 (m, 6H).