反应详情

温度

130 °C

A mixture of 2,2-difluoro-N′-hydroxy-N-(3,6-dimethylpyrazin-2-yl)ethanimidamide (3.05 g, 14.1 mmol, from Step D) and superphosphoric acid (100 mL) was heated to 130° C. with stirring for 18 h. The solution was added to ice and neutralized by addition of ammonium hydroxide. The dark aqueous solution was extracted three times with ethyl acetate, washed with brine, and dried over anhydrous magnesium sulfate. Concentration followed by flash chromatography (35% ethyl acetate/hexane) afforded the title compound as a yellow solid. LC/MS 199 (M+1).

1. additionThe solution was added to ice
2. extractionThe dark aqueous solution was extracted three times with ethyl acetate
3. washwashed with brine
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationConcentration