Reaktion #513202

Reaktionsgleichung

benzyloxycarbonyl chloride

sodium bicarbonate

sodium hydrosulfite

ethyl 2-cyano-2-hydroxyiminoacetate

→

ethyl 2-benzyloxycarbonylamino-2-cyanoacetate

Ausbeute 64.3%

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooling
2. 2
   Temperaturcooling
3. 3
   workup.ADDITIONAfter the addition
4. 4
   Sonstigeprecipitated crystals
5. 5
   Filtrationwere collected by filtration
6. 6
   Waschenwashed with sprayed water (50 ml×3)
7. 7
   SonstigeThe obtained crystals were recrystallized from ethanol (600 ml)
8. 8
   Filtrationfiltered
9. 9
   Waschenwashed with sprayed ethanol (50 ml×3)
10. 10
    Sonstigedried in airflow at 40° C.

Vorschrift

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%).

Quelle