6-Amino-3-chloropyridazine → Ethyl (6-chloroimidazo[1,2-b]pyridazin-2-yl)acetate

Participants

Reaction Steps

After 11.2 g of 3-amino-6-chloropyridazine was suspended in 150 mL of ethanol, 28.6 g of ethyl 4-chloroacetoacetate was added thereto and heated under reflux for 24 hours. After cooling, the mixture was concentrated under reduced pressure and the residue was adjusted to pH 7 by the addition of an aqueous sodium hydrogencarbonate solution and extracted with ethyl acetate. The extract was washed with a saline solution and dried over magnesium sulfate. After concentration under reduced pressure. The residue was subjected to silica gel chromatography to be eluted with hexane:ethyl acetate (2:3). The desired fraction was collected to provide 12.7 g of the title compound.

Provenance & Evidence