Reaktion #11517

Reaktionsgleichung

2-Amino-3-thiophencarboxamide

trichloroacetylisocyanate

ammonia

→

urea

2-[(Aminocarbonyl)amino]-3-thiophenecarboxamide

Lösungsmittel

methanol

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGStirring
2. 2
   workup.WAITwas continued for a further 3 h at room temperature
3. 3
   workup.STIRRINGstirring
4. 4
   workup.WAITwas continued for a further 2 h
5. 5
   SonstigeThe solvent was evaporated
6. 6
   workup.ADDITIONthe residue treated with water
7. 7
   FiltrationThe resultant solid was filtered off
8. 8
   Waschenwashed with more water

Vorschrift

2-Amino-3-thiophencarboxamide (0.44 g) was suspended in acetonitrile (25 ml) and trichloroacetylisocyanate (0.2 ml) added dropwise with stirring over 10 minutes. Stirring was continued for a further 3 h at room temperature and then a solution of ammonia in methanol (10 ml of a 2M solution) was added and stirring was continued for a further 2 h. The solvent was evaporated and the residue treated with water. The resultant solid was filtered off and washed with more water. Trituration with ether gave the title urea (0.2 g).

Quelle