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-4e5c34c20a4e4e56943aeee9530f5fd1

Source dataset

uspto-grants-2015_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08937071B2