Trimethyl borate → (4-((Pyridin-2-yloxy)methyl)phenyl)boronic acid

Under a nitrogen atmosphere, a solution of 2-[(4-bromobenzyl)oxy]pyridine (50 g, 190 mmol) in tetrahydrofuran (200 mL) was cooled to −78° C. and a 2.6M n-butyllithium hexane solution (88 mL, 228 mmol) was added thereto dropwise. After stirring for 45 minutes, trimethoxy borane (29.6 g, 285 mmol) was added thereto dropwise at the same temperature. After 30 minutes, a saturated aqueous solution of ammonium chloride and water were added thereto for quenching, and the solution was extracted with ethyl acetate. After the organic layer was washed with a mixture of saturated aqueous solution of ammonium chloride and saturated sodium chloride water and dried over anhydrous sodium sulfate, the solvent was evaporated under a reduced pressure. To the residue was added acetonitrile (200 mL), followed by suspending and stirring at 70° C. for 30 minutes, then, cooled, and stirred overnight at 4° C. The precipitated solid was filtered to obtain the title compound (11.2 g) as a white solid.

1. waitAfter 30 minutes
2. customfor quenching
3. extractionthe solution was extracted with ethyl acetate
4. washAfter the organic layer was washed with a mixture of saturated aqueous solution of ammonium chloride and saturated sodium chloride water
5. dry with materialdried over anhydrous sodium sulfate
6. customthe solvent was evaporated under a reduced pressure
7. additionTo the residue was added acetonitrile (200 mL)
8. stirringstirring at 70° C. for 30 minutes
9. temperaturecooled
10. stirringstirred overnight at 4° C
11. filtrationThe precipitated solid was filtered

ORD-Eintrag

ord-0fdbbf90714245b5886b0e90f66a33a0

Quelldatensatz

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08188119B2