Hydrochloric Acid → (5-Chloro-4-fluoro-2-methoxyphenyl)boronic acid

Temperature

-40 °C

2-Bromo-4-chloro-5-fluoroanisole (Reference Compound No. 16-1, 239 mg, 1.00 mmol) was dissolved in mixed solvent of anhydrous toluene (2 mL) and anhydrous tetrahydrofuran (0.5 mL), 1.6M hexane solution of n-butyl lithium (750 μL, 1.20 mmol) was added thereto at −40° C., and then the reaction mixture was stirred at the same temperature for 30 minutes. Triisopropyl boronic acid (277 μL, 1.20 mmol) was added dropwise to the reaction mixture, warmed to −20° C. over 10 minutes, and then 2N aqueous HCl solution (1 mL) was added. After the reaction mixture was stirred at room temperature for 20 minutes, ethyl acetate (20 mL) and water (20 mL) were added and partitioned. The organic layer was washed with saturated brine (20 mL), dried over anhydrous magnesium sulfate, and then the solvent was removed under reduced pressure to give the titled reference compound (181 mg) as a colorless solid. (Yield 89%)

1. additionwas added
2. temperaturewarmed to −20° C. over 10 minutes
3. stirringAfter the reaction mixture was stirred at room temperature for 20 minutes
4. custompartitioned
5. washThe organic layer was washed with saturated brine (20 mL)
6. dry with materialdried over anhydrous magnesium sulfate
7. customthe solvent was removed under reduced pressure

ORD record

ord-a44cfd994e4d492ba66244a24bbfa100

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08975256B2