反应详情

温度

65 °C

To a solution of N-(4-methoxyphenyl)acetamide II (7.50 g, 45.40 mmol) in acetic acid (50 mL) was added a solution of Br2 (4.70 mL, 90.80 mmol) in acetic acid (10.0 mL). The resulting reaction mixture was then heated to 65° C. for 4 h. After the completion of the reaction (TLC monitoring), acetic acid was distilled off, cooled the residue to 0° C. and then basified with aqueous NH3 till pH 12 followed by extraction with EtOAc (2×500.0 mL). The combined organics was washed with brine, dried (Na2SO4), filtered and concentrated under reduced pressure. The crude residue was purified over silica gel (60-120 M, 25-30% EtOAc-Hexane) to obtain the desired product (5.0 g, 45%). 1H NMR (400 MHz, DMSO-d6): δ 2.0 (s, 3H), 3.79 (s, 3H), 7.06 (d, J=8.80 Hz, 1H), 7.44 (dd, J=2.40 and 8.80 Hz, 1H), 7.91 (d, J=2.40 Hz, 1H) and 9.92 (br s, 1H). MS: 244.15 (M+H)+.

1. customThe resulting reaction mixture
2. distillationwas distilled off
3. temperaturecooled the residue to 0° C.
4. extractionfollowed by extraction with EtOAc (2×500.0 mL)
5. washThe combined organics was washed with brine
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe crude residue was purified over silica gel (60-120 M, 25-30% EtOAc-Hexane)