Boron trifluoride etherate → 4-Bromo-1-chloro-2-[[4-(trifluoromethoxy)phenyl]methyl]benzene

(5-bromo-2-chloro-phenyl)-[4-(trifluoromethoxy)phenyl]methanol 6g (4.37 g, 11.5 mmol) was dissolved in 35 mL dichloromethane, followed by addition of triethyl silane (5.49 mL, 34.4 mmol) and dropwise addition of boron trifluoride etherate (2.9 mL, 22.9 mmol). The reaction mixture was stirred for 16 hours. Thereafter, the reaction mixture was concentrated under reduced pressure and partitioned after 20 mL saturated sodium bicarbonate solution were added. The aqueous phase was extracted with dichloromethane (25 mL×3) and the organic extract was combined, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel chromatography with elution system C to obtain the title compound 4-bromo-1-chloro-2-[[4-(trifluoro-methoxy)phenyl]methyl]benzene 6h (3.0 g, colourless grease), yield: 71.6%. 1H NMR (400 MHz, CDCl3): δ 7.33-7.29 (m, 2H), 7.26-7.24 (m, 1H), 7.21-7.18 (m, 2H), 7.15 (d, 2H), 4.06 (s, 2H).

1. concentrationThereafter, the reaction mixture was concentrated under reduced pressure
2. custompartitioned after 20 mL saturated sodium bicarbonate solution
3. additionwere added
4. extractionThe aqueous phase was extracted with dichloromethane (25 mL×3)
5. extractionthe organic extract
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationfiltered
8. concentrationThe filtrate was concentrated under reduced pressure
9. customThe resulting residue was purified by silica gel chromatography with elution system C

ORD record

ord-db2f3718f0b74746b477b2688b0f2093

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08609622B2