反应详情

To a solution of methyl 4,6-dichloro-pyridazine-3-carboxylate (6.01 g, 29.03 mmol, WO 2004/031174) in THF (29 ml) at 0° C. is added 29 ml of aqueous 1.0 M LiOH with stirring. The resulted mixture is stirred continuously at 0° C. for 40 min and monitored by TLC. The reaction mixture is diluted with water, and acidified to pH 1-2 with aqueous 1.0 M HCl. The crude product is suspended between the organic and aqueous layers. After filtration and washed with water and hexane, and dried under vacuum, the product is obtained.

1. stirringThe resulted mixture is stirred continuously at 0° C. for 40 min
2. filtrationAfter filtration
3. washwashed with water and hexane
4. customdried under vacuum
5. customthe product is obtained