Triisopropyl borate → 3-Borono-4-fluorobenzoic acid

Temperature

-78 °C

To solution of 3-Bromo-4-fluoro-benzoic acid (1.0 eq) in THF (0.2M) at −78° C. was added n-BuLi (2.5M in Hex; 2.2 eq). The resulting mixture was stirred at −78° C. for 15 min then tri-isopropoxy borane (2.2 eq). The final mixture was stirred 1 h at −78° C. then 4 h at room temperature and finally poured in HCl (10%). After stirring for 12 h, THP was evaporated and the residual mixture was diluted with EtOAc. The organic extract was washed with HCl (10%), brine, dried over MgSO4, filtered and concentrated. The residue was suspended in EtOAc, stirred for 4 h and the desired compound was isolated by filtration.

1. stirringAfter stirring for 12 h
2. customTHP was evaporated
3. additionthe residual mixture was diluted with EtOAc
4. extractionThe organic extract
5. washwas washed with HCl (10%), brine
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated
9. stirringstirred for 4 h

ORD record

ord-8c113f86f6b94efcb76b87754e5c89c9

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07144896B2