Pyridine → 2-Chloro-3-hydrazinopyrazine

Participants

Reaction Conditions

Reaction Steps

A mixture of 2,3-dichloropyrazine (6.26 g, 42.0 mmol) and anhydrous hydrazine (5 mL, 159 mmol) in pyridine (22 mL, 272 mmol) was stirred at 60° C. for 2.5 h. After cooling to room temperature, the reaction mixture was concentrated in vacuo. The obtained residue was triturated with water. The resulting slurry was filtered, and the collected solid air dried to yield the first crop of the title compound (3.88 g) as a white solid. The filtrate was concentrated in vacuo, the obtained residue was treated by repeating above process to afford additional amount of the product (1.73 g). (total 5.61 g, 92% yield). HPLC/MS (Method C): retention time=0.30 min, [M+H]+=144.8. 1H NMR (500 MHz, DMSO-d6): δ 8.27 (s, 1H), 8.05 (s, 1H), 7.56 (s, 1H), 4.32 (s, 2H); 13C NMR (500 MHz, DMSO-d6) δ 152.62, 140.67, 132.60, 130.01.

Provenance & Evidence