反应详情

To a suspension of 5-bromo-3-chloro-6-aminopyridazine (15.7 g, 75.3 mmol) in dry DMF (80 mL) was added ethyl bromopyruvate (21.0 mL, 151 mmol) via a syringe. The resulting mixture was stirred at rt for 20 h. The reaction mixture was poured into ice water (300 mL), and the precipitated solid was isolated by filtration, and washed with water (2×50 mL) and Et2O (3×50 mL). The residual solvents in the solid were removed under reduced pressure to give compound 5a as an off-white solid. 1H-NMR (400 MHz, CDCl3) δ (ppm): 8.50 (s, 1H), 7.47 (s, 1H), 4.49 (q, J=7.1 Hz, 2H), 1.44 (t, J=7.1 Hz, 3H).

1. customthe precipitated solid was isolated by filtration
2. washwashed with water (2×50 mL) and Et2O (3×50 mL)
3. customThe residual solvents in the solid were removed under reduced pressure