反应详情

温度

70 °C

To a solution of 4-bromo-2-iodoaniline (750 g, 2.51 mol, 1.0 equiv) in DMF (5.0 L) was added ethyl acrylate (277 g, 2.76 mol, 1.1 equiv, Avra) and sodium bicarbonate (680 g, 6.29 mol, 2.5 equiv). The reaction mixture was degassed with nitrogen for 20 min followed by the addition of palladium acetate (28.8 g, 128.27 mmol, 0.05 equiv, Hindustan Platinum). The reaction mixture was heated at 70° C. for 3 h. The reaction was filtered through celite and the celite bed was washed with ethyl acetate (2×500 mL). The filtrate was concentrated under reduced pressure to obtain the crude residue which was purified by column chromatography (silica gel; mesh size 60-120, elution 0-20% ethyl acetate in hexanes) to obtain (E)-ethyl 3-(2-amino-5-bromophenyl)acrylate (620 g, 77.0%), as yellow solid. TLC solvent system: 20% ethyl acetate in hexanes. Product's Rf: 0.4. MS (ESI, positive ion) m/z; 270.2 (M+1). 1H NMR (400 MHz, DMSO) δ 7.75 (d, J=16.1 Hz, 1H), 7.57 (d, J=2.0 Hz, 1H), 7.16 (dd, J=9.1, 2.4 Hz, 1H), 6.66 (d, J=8.6 Hz, 1H), 6.43 (d, J=8.6 Hz, 1H), 5.81 (s, 2H), 4.20 (q, J=7.2 Hz, 2H), 1.27 (t, J=7.2 Hz, 3H).

1. customThe reaction mixture was degassed with nitrogen for 20 min
2. filtrationThe reaction was filtered through celite
3. washthe celite bed was washed with ethyl acetate (2×500 mL)
4. concentrationThe filtrate was concentrated under reduced pressure
5. customto obtain the crude residue which
6. customwas purified by column chromatography (silica gel; mesh size 60-120, elution 0-20% ethyl acetate in hexanes)