反应详情

[step 1] 3-Methylpyrazin-2-amine (16 g, 147 mmol) was dissolved in 1,2-dimethoxyethane (122 mL) and THF (61 mL), 2-bromo-1-cyclopropylethanone (36 g, 220 mmol) was added, and the mixture was stirred at room temperature for 70 hr. Saturated aqueous sodium hydrogen carbonate solution was added to the mixture, and the mixture was extracted 3 times with chloroform. The combined organic layers were dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform/methanol=100/0 v/v-85/15 v/v) to give 2-cyclopropyl-8-methylimidazo[1,2-a]pyrazine (11g, 43%).

1. extractionthe mixture was extracted 3 times with chloroform
2. dry with materialThe combined organic layers were dried over anhydrous magnesium sulfate
3. concentrationconcentrated under reduced pressure
4. customThe residue was purified by silica gel column chromatography (chloroform/methanol=100/0 v/v-85/15 v/v)