Sulfuric Acid → HCID 178493795, Verbindung

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 2-amino-3,5-dimethoxypyrazine (0.02 mole) in 300 ml. of 6 M sulfuric acid at 0°-5° C. is treated with 0.022 mole sodium nitrite in 25 ml. of water at such a rate to insure that the temperature of the reaction mixture does not rise above 5° C. After standing 45 minutes at 0°-5° C., a little urea is added to destroy excess nitrous acid and the mixture then is treated with sodium hydroxide solution until strongly basic. The reaction mixture is warmed to 60° C. for one hour and then brought to pH 8.5. The mixture is concentrated to a third of the original volume and cooled in the refrigerator overnight. The product is separated by filtration and dried in vacuo, recrystallized from a suitable solvent to give 2-hydroxy-3,5-dimethoxypyrazine.

Herkunft & Nachweise