反应详情

温度

60 °C

A solution of methyl (2S)-2-{[N-(tert-butoxycarbonyl)-L-alanyl]amino}-3-oxobutanoate (3.05 g, 10.1 mmol) and 4N hydrochloric acid in 1,4-dioxane (10 mL) was stirred at room temperature. After being stirred for 1 h at same temperature, the reaction mixture was concentrated in vacuo. A solution of the residue in pyridine (50 mL) was heated at 60° C. for 4 h. After being cooled to ambient temperature, the mixture was concentrated in vacuo. The residue was poured into water, and the mixture was extracted with dichloromethane. The organic layer was washed with saturated brine, dried over magnesium sulfate, filtrated and concentrated in vacuo. The residue was triturated with hexane-ethyl acetate (1:1) to give methyl 6-hydroxy-3,5-dimethylpyrazine-2-carboxylate. MS (APCI): m/z 183 (M+H).

1. concentrationthe reaction mixture was concentrated in vacuo
2. temperatureAfter being cooled to ambient temperature
3. concentrationthe mixture was concentrated in vacuo
4. additionThe residue was poured into water
5. extractionthe mixture was extracted with dichloromethane
6. washThe organic layer was washed with saturated brine
7. dry with materialdried over magnesium sulfate
8. filtrationfiltrated
9. concentrationconcentrated in vacuo
10. customThe residue was triturated with hexane-ethyl acetate (1:1)