 Reduction of norethisterone (1) affords the 3,17-diol.The 3β-hydroxy compound is the desired product; since reactions at C3 do not show nearly the stereoselectivity as those at C17 by virtue of the relative lack of stereo-directing proximate substituents, the formation of the desired isomer is engendered by use of a bulky reducing agent, lithium tri-tert-butoxyaluminum hydride.Acetylation of the 3β,17β-diol affords etynodiol diacetate (3).