Phosphorus tribromide → 1-(Bromomethyl)-2-chloro-3-(trifluoromethyl)benzene

Phosphorus tribromide (11.75 ml, 125 mmol) was added to a solution of crude (2-chloro-3-(trifluoromethyl)phenyl)methanol (9.37 g, 44.5 mmol) in dioxane (200 ml). The reaction mixture was stirred for 1 hour. Another portion of phosphorus tribromide (11.75 ml, 125 mmol) was added. The reaction mixture was stirred for 16 hours at room temperature. It was diluted with ethyl acetate (200 ml). A 10% aqueous solution of sodium hydrogensulphate (200 ml) was added, while cooling with a water bath. The phases were separated. The organic phase was washed with a 10% aqueous solution of sodium hydrogensulphate (100 ml). The combined aqueous layers were extracted with ethyl acetate (100 ml). The combined organic layers were washed with a saturated aqueous solution of sodium hydrogencarbonate (100 ml) and dried over magnesium sulphate. The solvent was removed in vacuo. The crude product was purified by flash chromatography on silica (150 g), using ethyl acetate/heptane (1:3) as eluent, to give 6.94 g of 1-(bromomethyl)-2-chloro-3-(trifluoromethyl)benzene.

1. stirringThe reaction mixture was stirred for 16 hours at room temperature
2. temperaturewhile cooling with a water bath
3. customThe phases were separated
4. washThe organic phase was washed with a 10% aqueous solution of sodium hydrogensulphate (100 ml)
5. extractionThe combined aqueous layers were extracted with ethyl acetate (100 ml)
6. washThe combined organic layers were washed with a saturated aqueous solution of sodium hydrogencarbonate (100 ml)
7. dry with materialdried over magnesium sulphate
8. customThe solvent was removed in vacuo
9. customThe crude product was purified by flash chromatography on silica (150 g)

ORD record

ord-98e8a03d07d3424a98c7d31bbdec5b58

Source dataset

uspto-grants-2003_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06610721B2