反应详情

To the solution of 13 (2.29 g, 6.31 mmol) in 23 ml of ethanol was added 6.87 ml of NH4OH. The reaction mixture was stirred at room temperature for 10 minutes, and the clear solution was refluxed for 12 hours. The solvent was removed under reduced pressure and the residue was suspended in saturated Na2CO3 solution. The solid was collected, washed sequentially with H2O and Et2O and dried to give the title compound as a white solid (1.16 g, 90%), mp 208° C. 1H NMR (600 MHz, DMSO-d6): δ 7.39 (d, J=8.6 Hz, 1H), 7.02 (d, J=2.4 Hz, 1H), 6.79 (dd, J=8.6 and 2.4 Hz, 1H), 5.79 (br s, 3H); 13C NMR: δ 155.38, 130.69, 130.28, 124.30, 123.50. IR: 1684, 1624, 1559, 1472, 1380, 1328, 869, 818, 671 cm−1. MS (m/z): 204 (M+), 187, 162, 127, and 90.

1. temperaturethe clear solution was refluxed for 12 hours
2. customThe solvent was removed under reduced pressure
3. customThe solid was collected
4. washwashed sequentially with H2O and Et2O
5. customdried