反应详情

N-Bromosuccinimide (29.1 g, 163.7 mmol) was added as a suspension in CH2Cl2 (200 mL) over 2 h to a solution of 2-ethylphenol (20.0 gm, 163.7 mmol), diisopropylethylamine (2.3 mL, 16.4 mmol), and CH2Cl2 (300 mL). The resulting solution was maintained at room temperature for 2 h. One normal HCl (100 mL) was added and the mixture was stirred vigorously for 0.5 h. The layers were separated, and the organic phase was washed with 1 N HCl (2×100 mL). The combined aqueous layers were extracted with CH2Cl2 (1×100 mL), dried (Na2SO4), filtered, and concentrated. The residue was purified by silica gel chromatography (SiO2, gradient elution 5 to 10% CH2Cl2/hexanes) to yield 26.5 g (80%) of 2-bromo-6-ethylphenol 1 as a yellow oil.

1. customThe layers were separated
2. washthe organic phase was washed with 1 N HCl (2×100 mL)
3. extractionThe combined aqueous layers were extracted with CH2Cl2 (1×100 mL)
4. dry with materialdried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by silica gel chromatography (SiO2, gradient elution 5 to 10% CH2Cl2/hexanes)