Dimethylformamide → 3-Chloropyrazine-2-carbonitrile

Beteiligte Stoffe

Reaktionsschritte

In 90 ml of benzene and 9.2 ml of dimethylformamide there was stirred at room temperature cyanopyrazine (12.7 g; 0.12 M) prepared in Step A above, after which there was added over 10 minutes sulfonyl chloride (64.79 g; 0.48 M). The reaction mixture was stirred for 30 minutes in an ice bath, then allowed to warm up to room temperature gradually, after which it was stirred for 5 hours. The benzene layer was decanted, and the reddish oil residue was extracted three times with ether, after which the combined benzene and ether layers were quenched with ice water and cooled in an ice bath. The combined layers were then neutralized with solid sodium bicarbonate, then separated, and the aqueous layer was extracted with ether. The combined organic layers were washed once with a small amount of water, dried with sodium sulfate, filtered, and the solvent evaporated to give the title compound (11 g).

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