Trimethyl borate → {4-[(Cyclobutyloxy)methyl]-2,6-dimethoxyphenyl}boronic acid

To a mixture of 2-bromo-5-[(cyclobutyloxy)methyl]-1,3-dimethoxybenzene (2.39 g, 7.94 mmol) and THF (20 mL) was added n-butyllithium (2.73 M solution in n-hexane: 3.49 mL, 9.53 mmol) at −78° C. (internal temperature), and the mixture was stirred for 1 hour. After then adding trimethyl borate (1.07 mL, 9.53 mmol) to the mixture, the temperature was slowly raised to room temperature while stirring. A saturated aqueous solution of ammonium chloride was added to the reaction mixture while cooling on ice, and then ethyl acetate was added. After thoroughly shaking the mixture, the organic layer was separated and the organic layer was washed with brine and dried over anhydrous magnesium sulfate. The mixture was filtered, and then the solvent in the filtrate was distilled off under reduced pressure. Heptane (30 mL) was added to the residue, the precipitated solid was collected by filtration and dried under reduced pressure to obtain the title compound (905 mg, 3.40 mmol).

1. stirringwhile stirring
2. temperaturewhile cooling on ice
3. stirringAfter thoroughly shaking the mixture
4. customthe organic layer was separated
5. washthe organic layer was washed with brine
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationThe mixture was filtered
8. distillationthe solvent in the filtrate was distilled off under reduced pressure
9. additionHeptane (30 mL) was added to the residue
10. filtrationthe precipitated solid was collected by filtration
11. customdried under reduced pressure

ORD record

ord-e8aea79186604c17884c60d4aedddc1e

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08431603B2