反应详情

A solution of N-[(pyrazin-2-ylamino) carbonothioyl]benzamide (25 g, 0.096 mol) in 10% NaOH solution (200 ml) is stirred at 80° C. for 20 min. The reaction mixture is cooled and the solvent is removed under vacuum. The residue is acidified with 2M HCl to pH=1 and then basified with ammonium hydroxide. The solid precipitated is collected by filtration and dried under suction affording N-Pyrazin-2-ylthiourea as a solid (12 g; 80%). 1H NMR (DMSO-d6, 300 MHz): δ 8.24 (br s, 2H), 8.54 (s, 1H), 9.10 (m, 1H), 9.95 (m, 1H), 10.66 (br s, 1H). M+ (ESI): 154.9. HPLC (Method B), Rt: 3.47 min (purity: 98.23%). TLC: Chloroform/methanol (9/1): Rf−0.25. Mp: 234° C.-235° C.

1. temperatureThe reaction mixture is cooled
2. customthe solvent is removed under vacuum
3. customThe solid precipitated
4. filtrationis collected by filtration
5. customdried under suction