Acetonitrile → 6-Isopropyl-2-methylimidazo[1,2-b]pyridazine

3-Amino-6-isopropylpyridazine (0.41 g, 2.99 mmol) and bromoacetone (0.53 g, 3.10 mmol) were mixed with acetonitrile (5.0 ml) and heated for 6 hours under reflux. After the reaction was completed, water (20.0 ml) was poured into the reaction solution and adjusted to pH 9 with 20% aqueous sodium hydroxide solution. The reaction solution was extracted twice with ethyl acetate, and the extracts were combined, dried over anhydrous sodium sulfate and concentrated. The residues were purified by silica gel column chromatography (ethyl acetate:chloroform=1:1) to give the title compound as brown oil. The yield was 0.30 g (57.2%).