反应详情

To a mixture of 2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol (10 g, 39 mmol) in 40% HBr (100 mL) was added dropwise a solution of sodium nitrite (3.2 g, 46 mmol) in water (10 mL). The mixture was stirred for 20 minutes before it was poured into a solution of copper(I) bromide (8.4 g, 59 mmol) in 40% HBr (100 mL) at 0° C. The resulting dark brown mixture was stirred for 30 minutes and was then diluted with water. The mixture was extracted with ethyl acetate (100 mL×3). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, and concentrated under vacuum. The residue was purified by chromatography on silica gel (5-10% ethyl acetate in petroleum ether) to afford 2-(4-bromophenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol (7.1 g, 57%). 1H NMR (300 MHz, CDCl3) δ 7.60 (s, 4H), 3.58 (s, 1H). MS (ESI) m/z (M−H+) 321.0.

1. stirringThe resulting dark brown mixture was stirred for 30 minutes
2. extractionThe mixture was extracted with ethyl acetate (100 mL×3)
3. washThe combined organic layers were washed with brine
4. dry with materialdried over anhydrous Na2SO4
5. concentrationconcentrated under vacuum
6. customThe residue was purified by chromatography on silica gel (5-10% ethyl acetate in petroleum ether)