The invention relates to a preparing method and a refining method for
milrinone. The preparing method comprises the following steps: an absolute ethyl
alcohol solution of 1-(4-pyridyl)-2-
acetone is added dropwise into an absolute ethyl
alcohol solution of ethoxymethylenemalononitrile, heat preservation is performed for 1-3 h under a condition of 20 DEG C-60 DEG C, then the temperature is increased to 75 DEG C-85 DEG C, a reaction liquid is cooled to 0-50 DEG C after a reaction is completed,
solid-liquid separation is performed, and a
solid is collected to obtain a product, wherein the
mass ratio of ethoxymethylenemalononitrile to 1-(4-pyridyl)-2-
acetone is (1.5-3):(1.5-2.5). According to the preparing method and the refining method, water is adopted to replace a purification
solvent such as DMF (
dimethyl formamide),
methanol,
ethanol and the like, so that not only are impurities removed effectively, all single impurities in a finished
milrinone product is smaller than 0.1%, and
solvent residues reach the standard, but also the production cost is reduced, product quality and yield are improved, and the methods are suitable for industrial production.