Reaktion #5551

Reaktionsgleichung

5-[2-(amino)ethylthio]imidazo[1,2-a]pyridine

triethylamine

o-acetylsalicyloyl chloride

→

desired product

Ausbeute 56.0%

5-[2-[2-(hydroxy)benzoylamino]ethylthio]imidazo[1,2-a]pyridine

Ausbeute 56.0%

Lösungsmittel

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooling
2. 2
   workup.STIRRINGthe mixture was stirred at room temperature for 30 minutes
3. 3
   workup.DISTILLATIONAfter the solvent was distilled off
4. 4
   workup.ADDITIONethanol (60 ml) and 1N NaOH (40 ml) were added to the residue
5. 5
   workup.STIRRINGby stirring for 1 hour
6. 6
   workup.ADDITION1N HCl (40 ml) was added
7. 7
   workup.DISTILLATIONethanol was distilled off
8. 8
   Extraktionthe residue was extracted with chloroform
9. 9
   Trocknendried over anhydrous magnesium sulfate
10. 10
    workup.DISTILLATIONAfter the solvent was distilled off
11. 11
    Sonstigethe residue was purified by column chromatography (eluent: ethyl acetate/ethanol=10:1)

Vorschrift

To a solution of 5-[2-(amino)ethylthio]imidazo[1,2-a]pyridine (3.87 g, 20 mmoles) and triethylamine (5.58 ml, 40 mmoles) in methylene chloride (200 ml) was added o-acetylsalicyloyl chloride (4.77 g, 24 mmoles) under ice-cooling with stirring and the mixture was stirred at room temperature for 30 minutes. After the solvent was distilled off, ethanol (60 ml) and 1N NaOH (40 ml) were added to the residue, followed by stirring for 1 hour. 1N HCl (40 ml) was added and ethanol was distilled off, and then the residue was extracted with chloroform and dried over anhydrous magnesium sulfate. After the solvent was distilled off, the residue was purified by column chromatography (eluent: ethyl acetate/ethanol=10:1) to obtain 3.51 g of the desired product (56.0%, colorless solid).

Quelle