Phosphorus tribromide → 1-Bromo-4-(bromomethyl)-2,3-difluorobenzene

Temperature

10 °C

To a solution of (4-bromo-2,3-difluorophenyl)methanol (500 mg, 2.242 mmol) in DCM (10 mL) stirred under N2 at 0° C. was added PBr3 (0.634 mL, 6.73 mmol) in one charge. The reaction mixture was stirred at 10° C. for 2 h. Then the solution was concentrated and distributed between DCM and saturated NaHCO3 solution. The combined organic extract was washed with brine, dried over MgSO4, filtered and concentrated. The crude material was purified by preparative TLC (PE/EA=10:1, Rf 0.6) to yield light yellow oil of 1-bromo-4-(bromomethyl)-2,3-difluorobenzene (330 mg, 1.154 mmol, 51.5% yield): 1H NMR (400 MHz, CDCl3) δ 7.30 (ddd, J=2.0, 6.0, 8.2 Hz, 1H), 7.11-7.03 (m, 1H), 4.46 (s, 2H).

1. additioncharge
2. concentrationThen the solution was concentrated
3. extractionThe combined organic extract
4. washwas washed with brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude material was purified by preparative TLC (PE/EA=10:1, Rf 0.6)

ORD record

ord-d1e85f8130b8405b82322f6488d0ddea

Source dataset

uspto-grants-2016_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09382238B2