Reaktion #214784

Reaktionsgleichung

1,2,5-trimethyl-β-oxo-3-pyrrolpropionitrile

toluene

phenylisocyanate

→

1,2,5-trimethyl-β-oxo-α-phenylcarbamoyl-3-pyrrolpropionitrile

Lösungsmittel

triethylamine

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwarmed for 5 minutes on the steam cone until
2. 2
   workup.DISSOLUTIONall is dissolved
3. 3
   Sonstigethe precipitate formed
4. 4
   Sonstigeis collected
5. 5
   workup.ADDITIONthe solution added to the mixture of 3 ml of 5 N hydrochloric acid and 250 ml of water
6. 6
   SonstigeThe crude product formed
7. 7
   Sonstigeis collected
8. 8
   Waschenwashed with water
9. 9
   workup.DISSOLUTIONdissolved in 5% aqueous sodium hydroxide
10. 10
    Filtrationfiltered
11. 11
    SonstigeThe precipitate is collected
12. 12
    Waschenwashed with water
13. 13
    Sonstigeair-dried
14. 14
    Sonstigerecrystallized from ethanol

Vorschrift

The suspension of 1.0 g of 1,2,5-trimethyl-β-oxo-3-pyrrolpropionitrile, 40 ml of toluene and 0.7 g of triethylamine is treated with 0.75 g of phenylisocyanate and warmed for 5 minutes on the steam cone until all is dissolved. After standing overnight, the precipitate formed is collected, taken up in methanol, and the solution added to the mixture of 3 ml of 5 N hydrochloric acid and 250 ml of water. The crude product formed is collected, washed with water, dissolved in 5% aqueous sodium hydroxide, filtered, and the alkaline filtrate acidified with 5 N hydrochloric acid. The precipitate is collected, washed with water, air-dried and recrystallized from ethanol, to yield the 1,2,5-trimethyl-β-oxo-α-phenylcarbamoyl-3-pyrrolpropionitrile melting at 158°-160°.

Quelle