反应详情

温度

2.5 °C

106 ml (1.10 moles) ethylchloroformate were dripped into a solution of 150 g (1.02 moles) DL-methionine amide in 200 ml water at 5-10° C., during which the pH was maintained at 7-9 by adding sodium hydroxide solution. A thick, finely crystalline precipitate rapidly formed. A suspension which was just able to still be agitated was obtained by the addition of 800 ml water, which suspension was agitated 3 hours further at room temperature. Then the colorless crystals were filtered off, washed with water and recrystallized out of 900 ml water. After cooling to 0-5° C., filtering off, washing with water and drying, 129 g (57%) Nαethoxycarbonyl-DL-methionine amide with a melting point of 110-112° C. was obtained.

1. temperaturewas maintained at 7-9
2. customA thick, finely crystalline precipitate rapidly formed
3. stirringwas agitated 3 hours further at room temperature
4. filtrationThen the colorless crystals were filtered off
5. washwashed with water
6. customrecrystallized out of 900 ml water
7. filtrationfiltering off
8. washwashing with water
9. customdrying