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 (2.73M n-hexane solution: 3.49 mL, 9.53 mmol) at −78° C. (internal temperature), and the mixture was stirred for one hour. To the mixture was added trimethyl borate (1.07 mL, 9.53 mmol) and the mixture was gradually warmed to room temperature while stirring. Thereafter, a saturated aqueous solution of ammonium chloride was added to the 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. To the residue, heptane (30 mL) was added, the precipitated solid was filtered and then 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. additionTo the residue, heptane (30 mL) was added
10. filtrationthe precipitated solid was filtered
11. customdried under reduced pressure

ORD record

ord-ab6cdbc9bb364cb0b51e3e5bd2e6b469

Source dataset

uspto-grants-2013_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08530504B2