14793-00-1

The general procedure for the synthesis of 6-chloro-2-methylimidazo[1,2-b]pyridazine from 3-amino-6-chloropyridazine and chloroacetone is as follows: to a solution of ethanol (15 mL) containing 6-chloropyridazin-3-amine (2.35 g, 18.1 mmol, 1.0 equiv.) was added sequentially 1-chloro-2-propanone (2.92 mL, 36.3 mmol, 2.0 equiv.) and triethylamine (2.53 mL, 18.1 mmol, 1.0 equiv). The reaction mixture was heated at 150 °C for 30 min and quenched with water upon completion of the reaction. The crude product was purified by column chromatography using a hexane solution of 30% ethyl acetate as eluent, resulting in 2.43 g of brown solid product in 80% yield.

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