反应详情

温度

50 °C

A solution of 5-(2-dimethylamino-vinyl)-pyrazine-2-carboxylic acid methyl ester (prepared as in Example 41, 600 mg, 2.9 mmol) in benzene (5 mL) was treated with a solution of a 1M aqueous hydrochloric acid solution (5 mL) and water (5 mL) and then stirred vigorously at 50° C. for 60 min. The mixture was cooled and then treated with sodium chloride (2 g). The mixture was extracted with benzene (3×25 mL). Each extract was washed with a saturated aqueous sodium chloride solution (2×20 mL). The combined organic extracts were dried over sodium sulfate, filtered, and concentrated in vacuo to afford 5-(2-oxo-ethyl)-pyrazine-2-carboxylic acid methyl ester (295 mg, 56%) as yellow crystals.

1. temperatureThe mixture was cooled
2. extractionThe mixture was extracted with benzene (3×25 mL)
3. washEach extract was washed with a saturated aqueous sodium chloride solution (2×20 mL)
4. dry with materialThe combined organic extracts were dried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo