3,5-DICHLOROPYRAZINE-2-CARBOXAMIDE synthesis

4774-14-5

77287-34-4

312736-50-8

The general procedure for the synthesis of 3,5-dichloropyrazine-2-carboxamide from 2,6-dichloropyrazine and the compound (CAS:77287-34-4) was as follows: to a mixed solution containing 2,6-dichloropyrazine (11.0 g, 73.8 mmol) and formamide (58.6 mL, 1,476 mmol) was slowly added dropwise sodium persulfate (17.1 g, 71.7 mmol). The reaction mixture was stirred at 90 °C for 2 hours, followed by continued stirring at room temperature for 12 hours. After completion of the reaction, the reaction mixture was diluted with water and then extracted with isopropanol/chloroform (1:3, v/v) and the organic phase was washed with brine. The organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (eluent: 70% n-hexane/ethyl acetate) to afford 3,5-dichloropyrazine-2-carboxamide (5.06 g, 36% yield) as an oil.