Reaktion #1464816

Reaktionsgleichung

2-(4-methylphenyl)-3-oxo-butyronitrile

ethanol

2,2-diethoxyethylhydrazine

hydrogen chloride

→

title compound

Ausbeute 72.3%

7-(4-Methylphenyl)-6-methyl-1H-imidazo[1,2-b]pyrazole

Ausbeute 72.3%

Lösungsmittel

diethyl ether

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated
2. 2
   Temperaturunder reflux for 7 hours
3. 3
   Temperaturthe whole mixture was heated
4. 4
   Temperaturunder reflux for a further 30 minutes
5. 5
   TemperaturAfter the mixture had been cooled
6. 6
   Sonstigeto precipitate crystals
7. 7
   FiltrationThese were collected by filtration
8. 8
   Sonstigepartitioned between ethyl acetate and dilute aqueous ammonia
9. 9
   SonstigeThe organic phase was separated
10. 10
    Waschenwashed with water
11. 11
    Trocknendried over anhydrous magnesium sulfate
12. 12
    SonstigeThe solvent was then removed by distillation under reduced pressure
13. 13
    Sonstigeto leave a residue, which
14. 14
    Sonstigewas recrystallized from a mixture of ethyl acetate and hexane

Vorschrift

A mixture of 1.7 g of 2-(4-methylphenyl)-3-oxo-butyronitrile, 20 ml of ethanol and 1.5 g of 2,2-diethoxyethylhydrazine was heated under reflux for 7 hours. At the end of this time, 30 ml of 4N hydrogen chloride in dioxane were added, and then the whole mixture was heated under reflux for a further 30 minutes. After the mixture had been cooled, diethyl ether was added to precipitate crystals. These were collected by filtration and partitioned between ethyl acetate and dilute aqueous ammonia. The organic phase was separated, washed with water and dried over anhydrous magnesium sulfate. The solvent was then removed by distillation under reduced pressure, to leave a residue, which was recrystallized from a mixture of ethyl acetate and hexane, to give 1.5 g of the title compound. The physical and chemical properties of this compound were the same as those of the compound prepared as described in Example 36.

Quelle