Triisopropyl borate → 4-Fluoro-3-(hydroxymethyl)benzeneboronic acid

Temperature

-78 °C

To solution of (5-bromo-2-fluoro-phenyl)-methanol (1.0 eq) in THF (0.1M) at −78° C. was added dropwise n-BuLi (2.5M in Hex; 2.2 eq). The resulting mixture was stirred at −78° C. for 30 min then tri-isopropoxy borane (2.2 eq) was added. The final mixture was stirred 15 min at −78° C. then allowed to warm slowly to room temperature and stirred an extra hour. The reaction was quenched with HCl (10%) and extracted with EtOAc (2×). The combined organic extracts were washed with brine, dried over MgSO4, filtered and concentrated. The residue was dissolved in EtOAc, water (few drops) was added then hexane until a precipitate formed. After 12 h of stirring, the desired compound was isolated by filtration as a white solid.

1. temperatureto warm slowly to room temperature
2. stirringstirred an extra hour
3. customThe reaction was quenched with HCl (10%)
4. extractionextracted with EtOAc (2×)
5. washThe combined organic extracts were washed with brine
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated
9. dissolutionThe residue was dissolved in EtOAc
10. additionwater (few drops) was added
11. customhexane until a precipitate formed
12. stirringAfter 12 h of stirring

ORD record

ord-51c6b43083f04340887795bdd1c95276

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07144896B2