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

Temperature

-78 °C

To a solution of 1-fluoro-4-iodo-2-isopropyl-5-methoxybenzene (Intermediate 5, 2.61 g, 8.88 mmol) in THF at −78° C., n-BuLi (4.26 mL, 10.65 mmol, 2.5 M) 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 ammonium chloride and the mixture was warmed to room temperature. The organic layer was extracted with ethyl acetate (3×50 mL). The combined ethyl acetate layers were washed with brine and dried over sodium sulfate. The title compound was obtained as a white solid. 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).

1. stirringThe solution was then stirred at −78° C. for 3 h
2. customThe reaction was quenched at −78° C. with saturated ammonium chloride
3. temperaturethe mixture was warmed to room temperature
4. extractionThe organic layer was extracted with ethyl acetate (3×50 mL)
5. washThe combined ethyl acetate layers were washed with brine
6. dry with materialdried over sodium sulfate

ORD record

ord-f1619c462d3c49e594e45729ac5dce08

Source dataset

uspto-grants-2014_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08865707B2