Methanol → Methyl 6-chloropyridazine-3-carboxylate

Beteiligte Stoffe

Reaktionsschritte

Oxalyl chloride (1.14 mL, 13.09 mmol), was added dropwise to an ice-cold suspension of 6-chloro-pyridazine-3-carboxylic acid [(1.9 g, 11.9 mmol), J. Het. Chem. 29(6), 1583-92; 1992] in a mixture of dichloromethane (50 mL) and N,N-dimethylformamide (1 drop) and the mixture was stirred for 1 hour at room temperature. The reaction mixture was then evaporated under reduced pressure and the residue was diluted with dichloromethane (30 mL) and cooled to 0° C. Methanol (485 μL, 11.9 mmol) was added and the mixture was stirred at 0° C. for 1 hour. Sodium hydrogen carbonate solution was then added to the reaction mixture and the aqueous layer was separated and extracted with dichloromethane (×2). The combined organic solutions were washed with brine, dried over sodium sulfate and concentrated in vacuo to afford the title compound as a white solid in 65% yield, 1.33 g.

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