Chloroacetaldehyde → 8-Bromo-6-chloroimidazo(1,2-b)pyridazine

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-bromo-6-chloropyridazin-3-amine (6.0 g, 28.8 mmol) was added 2-chloroacetaldehyde (22.60 g, 144 mmol) (50% water solution). The reaction mixture was heated to 50° C. overnight. The reaction mixture was cooled to room temperature and concentrated. The residue was diluted with CH2Cl2. Then, saturated NaHCO3 was added slowly until bubbling ceased. The layers were separated. The aqueous layer was extracted with CH2Cl2 (3×30 mL). The combined organic layer was washed with water and brine, dried over Na2SO4. The crude product was purified by BIOTAGE® (10-40% EtOAc/CH2Cl2, 2.1 L) to give 4.1 g (61%) product as a brown solid. 1H NMR (400 MHz, CDCl3) δ ppm 8.01 (1H, s), 7.84 (1H, s), 7.39 (1H, s); 13C NMR (101 MHz, CDCl3) δ ppm 145.92 (1 C, s), 136.93 (1 C, s), 134.77 (1 C, s), 124.20 (1 C, s), 121.22 (1 C, s), 118.81 (1 C, s).

Provenance & Evidence