The invention relates to a preparation method for 3,5-estradiene-3,17beta-diacetate. The preparation method comprises the following steps: sequentially adding nandrolone, p-toluenesulfonic acid monohydrate,
isopropyl acetate and magneton No. 15 into a reactor, introducing
condensed water, carrying out a heating reaction in an oil-bath pot and slowing adding
isopropenyl acetate when
reflux condensation of the obtained
system begins; after completion of a reaction, carrying out
evaporation to remove a
solvent; cooling the
system, adding
pyridine, and adding isopropanol drop by drop until a white
solid product is precipitated; carrying out low-temperature cooling and pumping
filtration and then carrying out cleaning with cold isopropanol; collecting the white
solid product and then carrying out
drying so as to obtain a pure 3,5-estradiene-3,17beta-diacetate product. According to the invention, nandrolone is used as a substrate and a one-pot method is employed for carbonyl and hydroxyl
acetylation protection so as to synthesize the product; the method is simple in process, mild in conditions and friendly to environment and has yield of up to 85%; and the synthesized product has critical application value in the fields of medicines,
veterinary drugs and pesticides and is an important pro-
drug for tibolone.