Azobisisobutyronitrile → 4-(Bromomethyl)-3,6-dichloro-5-methylpyridazine

To a stirred solution of 3,6-dichloro-4,5-dimethylpyridazine (500 mg, 2.82 mmol) in carbon tetrachloride (10 mL) was added N-bromosuccinimide (503 mg, 2.82 mmol), and AIBN (2.3 mg, 0.014 mmol) in a round bottom flask equipped with condenser. The reaction was continuously irradiated with a 300 W light and refluxed for 5 h. The formed succimide was filtered and the filtrate was concentrated to afford 4-(bromomethyl)-3,6-dichloro-5-methylpyridazine as a brown solid. To a solution of 4-(bromomethyl)-3,6-dichloro-5-methylpyridazine (400 mg, 1.56 mmol) in DMF was added with benzyl amine (188 μL, 1.72 mmol) and TEA (326 μL, 2.34 mmol). The reaction mixture was heated at 90° C. for 2 h, diluted with DCM and washed with water and brine. The organic layer was dried over Na2SO4 and concentrated to afford a brown oil. The crude material was purified by flash chromatography on silica gel, eluting with 30-80% EtOAc:heptane. Fractions containing the desired product were combined and concentrated to afford a the title compound as a greasy solid (430 mg, yield: 54% (two steps)).