Reaktion #44981

Reaktionsgleichung

sodium hydrogen carbonate

Ethyl 3-aminoisonicotinate

sulfuric acid

sodium nitrite

→

ethyl 3-hydroxyisonicotinate

Lösungsmittel

water

water

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction solution is cooled with ice
2. 2
   Temperatursame cooling conditions for 20 minutes
3. 3
   Extraktionfollowed by extraction with chloroform
4. 4
   TrocknenThe organic layer is dried over sodium sulfate
5. 5
   Sonstigeevaporated
6. 6
   Sonstigeto remove the solvent under reduced pressure
7. 7
   SonstigeThe resulting residue is purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=5/1)

Vorschrift

Ethyl 3-aminoisonicotinate (5.55 g) is suspended in water (70 ml), and thereto added conc. sulfuric acid (4.0 ml). The reaction solution is cooled with ice, and a solution of sodium nitrite (2.79 g) in water (30 ml) is added dropwise thereto. The reaction solution is stirred under the same cooling conditions for 20 minutes and then at 90° C. for 80 minutes. The reaction solution is diluted with water (100 ml) and the solution is adjusted to pH 8 to 9 by addition of saturated aqueous sodium hydrogen carbonate solution, followed by extraction with chloroform. The organic layer is dried over sodium sulfate and evaporated to remove the solvent under reduced pressure. The resulting residue is purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=5/1) to give ethyl 3-hydroxyisonicotinate (2.64 g).

Quelle