反应详情

温度

25 °C

To a mixture of ethyl 2-cyano-2-hydroxyiminoacetate (100 g, 0.704 mol) and water (600 ml), were added a saturated aqueous solution of sodium bicarbonate (200 ml) and sodium hydrosulfite (340 g, 1.96 mol) under ice-cooling, and then benzyloxycarbonyl chloride (144 g, 0.848 mol) was added dropwise under ice-cooling. After the addition was completed, the reaction solution was stirred at 20-30° C. for about 4 hours. Completion of the reaction was confirmed using TLC shown below, precipitated crystals were collected by filtration and washed with sprayed water (50 ml×3). The obtained crystals were recrystallized from ethanol (600 ml), filtered and washed with sprayed ethanol (50 ml×3), dried in airflow at 40° C. to give ethyl 2-benzyloxycarbonylamino-2-cyanoacetate (118.7 g, yield 64.2%).

1. temperaturecooling
2. temperaturecooling
3. additionAfter the addition
4. customprecipitated crystals
5. filtrationwere collected by filtration
6. washwashed with sprayed water (50 ml×3)
7. customThe obtained crystals were recrystallized from ethanol (600 ml)
8. filtrationfiltered
9. washwashed with sprayed ethanol (50 ml×3)
10. customdried in airflow at 40° C.