Reaktion #95666

Reaktionsgleichung

5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxamide

water

sodium hydroxide

→

5,6-dihydro-5-methyl-6-oxo-4H-imidazo[ 1,5-a][1,4]benzodiazepine-3-carbonitrile

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturto reflux
2. 2
   workup.ADDITIONThe mixture is treated with a 0.5 g portion of Sicapent after 16 hours, 19 hours and 24 hours
3. 3
   TemperaturThe mixture is subsequently cooled
4. 4
   SonstigeAfter separation of the organic phase
5. 5
   Extraktionthe alkaline-aqueous phase is extracted twice with 250 ml of ethyl acetate each time
6. 6
   WaschenThe organic extracts are washed twice with saturated sodium chloride solution
7. 7
   Sonstigedried
8. 8
   Sonstigeevaporated
9. 9
   SonstigeAfter crystallisation of the residue from methylene chloride/hexane, there
10. 10
    Sonstigeis recovered a portion
11. 11
    SonstigeThe mother liquor is evaporated
12. 12
    Sonstigechromatographed on 100 g of silica gel
13. 13
    Waschenwhile eluting with ethyl acetate and alcohol
14. 14
    SonstigeAfter recrystallisation of the thus-obtained substance from acetone

Vorschrift

0.5 g of 5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxamide is heated to reflux while stirring for 40 hours together with 0.5 g of Sicapent in 150 ml of toluene. The mixture is treated with a 0.5 g portion of Sicapent after 16 hours, 19 hours and 24 hours. The mixture is subsequently cooled and treated with water. The mixture is adjusted to pH 9 with 28 percent sodium hydroxide. After separation of the organic phase, the alkaline-aqueous phase is extracted twice with 250 ml of ethyl acetate each time. The organic extracts are washed twice with saturated sodium chloride solution, dried and evaporated. After crystallisation of the residue from methylene chloride/hexane, there is recovered a portion of unreacted starting material. The mother liquor is evaporated and chromatographed on 100 g of silica gel while eluting with ethyl acetate and alcohol. After recrystallisation of the thus-obtained substance from acetone, there is obtained 5,6-dihydro-5-methyl-6-oxo-4H-imidazo[ 1,5-a][1,4]benzodiazepine-3-carbonitrile of melting point 184°-185° C.

Quelle