反应详情

A mixture of 27.4 g (125.6 mmol) of 2-bromo-5-nitrophenol, 26 g (188.4 mmol) potassium carbonate, and 250 mL DMF were stirred 15 min at room temperature. 16.4 mL (138 mmol) of benzyl bromide was added in one portion to the reaction mixture and the mixture was heated to 90° C. TLC analysis indicated complete reaction, so the reaction mixture was cooled to 5° C. in an ice/water bath, filtered and concentrated. 300 mL water was added to the reaction mixture and the black precipitate was filtered and air dried. The crude product was taken up in dichloromethane and purified over silica eluting with 35% hexanes in dichloromethane, to give 2-bromo-5-nitro-O-benzylphenol 35.5 g (115.2 mmol, 91.7%) as an ivory solid. 1H NMR (400 MHz) CDCl3 7.78 (s, 1H), 7.72 (s, 2H), 7.46-7.48 (m, 2H), 7.38-7.42 (m, 2H), 7.32-7.35 (1H), 5.23 (s, 2H).

1. temperaturethe mixture was heated to 90° C
2. customreaction
3. temperatureso the reaction mixture was cooled to 5° C. in an ice/water bath
4. filtrationfiltered
5. concentrationconcentrated
6. addition300 mL water was added to the reaction mixture
7. filtrationthe black precipitate was filtered
8. customair dried
9. custompurified over silica eluting with 35% hexanes in dichloromethane