Reaktion #214777

Reaktionsgleichung

1-ethyl-β-oxo-2-pyrrolpropionitrile

toluene

phenylisocyanate

→

1-ethyl-β-oxo-α-phenylcarbamoyl-2-pyrrolpropionitrile

Lösungsmittel

triethylamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeevaporated
2. 2
   workup.DISSOLUTIONthe residue dissolved in methanol
3. 3
   workup.ADDITIONThe solution is poured into 300 ml of water containing 5 ml of 5 N hydrochloric acid
4. 4
   Sonstigethe precipitate is collected
5. 5
   workup.DISSOLUTIONIt is dissolved in 5% aqueous sodium hydroxide
6. 6
   Filtrationthe solution filtered
7. 7
   Sonstigethe filtrate re-acidified, the solids collected
8. 8
   Waschenwashed with water
9. 9
   Sonstigedried
10. 10
    Sonstigerecrystallized from ethanol

Vorschrift

The mixture of 2.1 g of 1-ethyl-β-oxo-2-pyrrolpropionitrile, 25 ml of toluene and 1.6 g of triethylamine is treated with 1.6 g of phenylisocyanate while stirring. It is allowed to stand overnight at room temperature, evaporated and the residue dissolved in methanol. The solution is poured into 300 ml of water containing 5 ml of 5 N hydrochloric acid and the precipitate is collected. It is dissolved in 5% aqueous sodium hydroxide, the solution filtered, the filtrate re-acidified, the solids collected, washed with water, dried and recrystallized from ethanol, to yield the 1-ethyl-β-oxo-α-phenylcarbamoyl-2-pyrrolpropionitrile melting at 144°-145°.

Quelle