Dimethyl Sulfoxide → Ethyl 3-chloropyridazine-6-acetate

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-(6-chloro-pyridazin-3-yl)-malonic acid diethyl ester (from step 1, ca. 65%, 19.0 g), sodium chloride (11.8 g), water (1.3 mL), and dimethyl sulfoxide (80 mL) was stirred at 150° C. for 4.5 h. More sodium chloride (5.0 g) and water (0.6 mL) were then added and stirring was continued at 160° C. for another 2 h. After cooling to room temperature, water was added and the resulting mixture was extracted with tert-butyl methyl ether. The combined extracts were washed with water and brine and dried (MgSO4). The solvent was evaporated to give the crude title compound that was submitted to the next reaction step without further purification. Yield: 9.0 g (64% of theory); LC (method 1): tR=1.18 min.

Provenance & Evidence