Patent / 1973
16.alpha.,-17-Epoxypregnane-3,11,20-trione was ketalized with HOCH2CH2- OH and then reduced by KBH4 to give the bis(ethylenedioxy) pregnanediol I, which reacted with MeMgBr to give pregnenedione II, after hydrolysis. The 2,4-dibromo deriv. of II was debrominated in DMF contg. Li2- CO3 and LiBr to give the title compd. III.