Reaktion #302870

Reaktionsgleichung

phenylisocyanate

2-aminonicotinic acid methyl ester

→

3-phenyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione

Ausbeute 61.2%

Lösungsmittel

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was refluxed for 16 hours
2. 2
   SonstigeThe pyridine is was removed under reduced pressure
3. 3
   workup.ADDITIONthe residue was treated with 280 ml ethanol
4. 4
   TemperaturThe mixture is refluxed for 10 minutes
5. 5
   TemperaturUpon cooling down 3-phenyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione
6. 6
   Sonstigecrystallized from the medium
7. 7
   Sonstigewas recrystallized from methoxypropanol

Vorschrift

17.22 g (144.6 mmol, 15.7 ml) phenylisocyanate was added to a suspenssion of 7.00 g (46.0 mmol) 2-aminonicotinic acid methyl ester in dry pyridine. The mixture was refluxed for 16 hours. The pyridine is was removed under reduced pressure and the residue was treated with 280 ml ethanol. The mixture is refluxed for 10 minutes. Upon cooling down 3-phenyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione crystallized from the medium and was recrystallized from methoxypropanol. 6.73 g (61%) 3-phenyl-1H-pyrido[2,3-d]pyrimidine-2,4-dione was isolated (m.p. 304° C.).

Quelle