反应详情

温度

80 °C

A solution of ethylamine in methanol solution (2.0M; 40 mL; 80 mmol) was added to a stirred suspension of 5-(2,4-bis-benzyloxy-5-chlorophenyl)-isoxazole-3-carboxylic acid ethyl ester (4.40 g; 9.51 mmol) in absolute ethanol (50 ml). The reaction mixture was heated to 80° C. (oil-bath temperature) for five hours. The reaction mixture was allowed to cool to ambient temperature and left to stand overnight. A colourless solid product formed and the reaction mixture was further cooled in an ice-water bath, filtered and washed with cold ethanol (2×20 ml). The colourless product was dried in vacuo to afford 5-(2,4-bis-benzyloxy-5-chlorophenyl)-isoxazole-3-carboxylic acid ethylamide 3.42 g (78%) LCMS: [M+H]+ 465, 463 (37Cl; 35Cl). 1H NMR (400 MHz, CDCl3) δ 1.25 (t, 3H), 3.48 (m, 2H), 5.10 (s, 2H), 5.2 (s, 2H), 6.59 (s, 1H), 6.83 (brt, 1H), 7.08 (s, 1H), 7.30-7.41 (m, 10H), 7.97 (s, 1H).

1. temperatureto cool to ambient temperature
2. waitleft
3. customA colourless solid product formed
4. temperaturethe reaction mixture was further cooled in an ice-water bath
5. filtrationfiltered
6. washwashed with cold ethanol (2×20 ml)
7. customThe colourless product was dried in vacuo