Reaktion #63795

Reaktionsgleichung

1-bromo-2-(4-methylphenyl)-2-ethanone

2-amino-5-nitropyridine

→

yellow solid

Ausbeute 23.0%

2-(4-Methylphenyl)-6-nitroimidazo[1,2-a]pyridine

Ausbeute 23.0%

Lösungsmittel

dichloromethane

n-propanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe solution is maintained
2. 2
   Temperaturunder reflux
3. 3
   Sonstigethe mixture is evaporated to dryness
4. 4
   workup.ADDITIONtreated with ammonia solution until the pH>8
5. 5
   FiltrationThe insoluble material is filtered off
6. 6
   Sonstigedried
7. 7
   workup.ADDITIONtreated with dichloromethane
8. 8
   SonstigeThe insoluble portion is recrystallized in ethyl acetate
9. 9
   Sonstigewhich yields a first crop
10. 10
    Einengenthe mixture is concentrated
11. 11
    Sonstigea second crop of product is obtained
12. 12
    SonstigeThe two crops are purified separately by chromatography

Vorschrift

81 g (0.38 mole) of 1-bromo-2-(4-methylphenyl)-2-ethanone and 53 g (0.38 mole) of 2-amino-5-nitropyridine are reacted in 900 ml of n-propanol. The solution is maintained under reflux, the reaction being followed by thin layer chromatography. When there is no further change, the mixture is evaporated to dryness. The residue is taken up with water and treated with ammonia solution until the pH>8. The insoluble material is filtered off and dried, and then treated with dichloromethane. The insoluble portion is recrystallized in ethyl acetate, which yields a first crop. The mother liquors are then combined with the portion soluble in dichloromethane, the mixture is concentrated and a second crop of product is obtained. The two crops are purified separately by chromatography. 22 g (23%) of yellow solid are obtained overall. M.p. 205°-206° C.

Quelle