Reaktion #934898

Reaktionsgleichung

water

sodium hydride

1-[3-hydroxy-3-(2-naphthyl)-n-propyl]imidazole

Methyl iodide

→

1-[3-methoxy-3-(2-naphthyl)-n-propyl]imidazole

Lösungsmittel

hexamethylphosphoramide

hexamethylphosphoramide

dichloromethane

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled in ice
2. 2
   workup.STIRRINGwith stirring
3. 3
   Temperaturmaintaining the temperature below 10° C.
4. 4
   workup.STIRRINGthe mixture stirred at 5° C. for 1 hour and overnight at room temperature
5. 5
   Extraktionthe product extracted with ether
6. 6
   Waschenthe extracts washed
7. 7
   Trocknendried (MgSO4)
8. 8
   Sonstigeevaporated
9. 9
   Sonstigeto give a yellow oil

Vorschrift

A solution of 1.2 g of 1-[3-hydroxy-3-(2-naphthyl)-n-propyl]imidazole in 20 ml of dry hexamethylphosphoramide is treated between 5°-10° C. with stirring under nitrogen with 0.24 g of a 50% dispersion of sodium hydride in mineral oil. The mixture is stirred one hour at 10° C., one hour at 50° C., and then cooled in ice. Methyl iodide (0.8 g.) in 2 ml of hexamethylphosphoramide is added with stirring maintaining the temperature below 10° C. and the mixture stirred at 5° C. for 1 hour and overnight at room temperature. The resulting mixture is poured into water, the product extracted with ether and the extracts washed, dried (MgSO4) and evaporated to give a yellow oil. Chromatography on silica gel eluting with 10% methanol in dichloromethane gives pure 1-[3-methoxy-3-(2-naphthyl)-n-propyl]imidazole. This is converted to its hydrogen sulfate addition salt by dropwise addition of sulfuric acid to a solution in ether and recrystallized from methanol/ethyl acetate to give 1-[3-methoxy-3-(2-naphthyl)-n-propyl]imidazole hydrogen sulfate, m.p. 122°-122.5° C.

Quelle