Methyl 6-chloropyridazine-3-carboxylate → HCID 89581292, compound

Participants

Reaction Conditions

Reaction Steps

A solution of methyl 6-chloropyridazine-3-carboxylate (1.5 g, 8.7 mmol), ethoxyvinyl tin (3.2 g, 8.7 mmol), trans-bis(triphenyl-phosphine)palladium (200 mg) and N,N-dimethylformamide (50 mL) were combined. The mixture solution was heated to 80° C. for 10 hours under nitrogen gas protected. N,N-dimethylformamide was concentrated to dry in vacuo. The residue was purified by column chromatography (silica-gel, petroleum/ethyl acetate=4:1) to give methyl 6-(1-ethoxyvinyl)pyridazine-3-carboxylate as a white solid (1.3 g, 72%). 1H NMR (300 MHz, CDCl3): δ 8.22 (d, J=9 Hz, 1H), 7.98 (d, J=9 Hz, 1H), 4.98 (d, J=2.4 Hz, 1H), 4.68 (d, J=Methyl 6-acetylpyridazine-3-carboxylate. A solution of methyl 6-(1-ethoxyvinyl)pyridazine-3-carboxylate (1.3 g, 7.2 mmol) in hydrochloric acid (6 mol/L, 20 mL) was stirred at room temperature for 4 hours. The mixture solution was neutralized with potassium carbonate, extracted with ethyl acetate (100 mL). The organic layer was concentrated to dry to give methyl 6-acetylpyridazine-3-carboxylate as a white solid (0.9, 81%). 1H NMR (300 MHz, CDCl3): δ 8.36-8.40 (m, 1H), 8.36-8.40 (m, 1H), 4.00 (s, 3H), 2.82 (s, 3H).

Provenance & Evidence