Reacción #1464816

Ecuación de reacción

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

ethanol

2,2-diethoxyethylhydrazine

hydrogen chloride

→

title compound

Rendimiento 72.3%

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

Rendimiento 72.3%

Disolventes

diethyl ether

dioxane

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturawas heated
2. 2
   Temperaturaunder reflux for 7 hours
3. 3
   Temperaturathe whole mixture was heated
4. 4
   Temperaturaunder reflux for a further 30 minutes
5. 5
   TemperaturaAfter the mixture had been cooled
6. 6
   Otroto precipitate crystals
7. 7
   FiltraciónThese were collected by filtration
8. 8
   Otropartitioned between ethyl acetate and dilute aqueous ammonia
9. 9
   OtroThe organic phase was separated
10. 10
    Lavadowashed with water
11. 11
    Secadodried over anhydrous magnesium sulfate
12. 12
    OtroThe solvent was then removed by distillation under reduced pressure
13. 13
    Otroto leave a residue, which
14. 14
    Otrowas recrystallized from a mixture of ethyl acetate and hexane

Procedimiento

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.

Fuente