Reactions of 1-Chloro-3-buten-2-ol 2955 enins), XI, and in a total synthesis of the sex hormone equilenin, XII. In the latter case the procedures have been refined so that the racemic form of the hormone can be prepared in about 28% over-all yield in eight steps from l-keto-7-methoxy-1,2,3,4-tetrahydrophenanthrene, Ilia. The steps involve formylatioti (step 1) followed by treatment with hydroxylamine (step 2) to produce an isoxazole Va, which is isomerized with alkoxide and methylated (step 3) to give the cyano ketone Vila. Condensation of Vila with dimethyl suc-cinate in the presence of potassium i-butoxide (step 4) affords, in one operation, 15-carbomethoxy-14,15-dehydroequilenin methyl ether, Villa (R' = CHg), which is hydrolyzed (step 5) to the free acid IXa, and decarboxylated (step 6) to give 14,15-dehydroequilenin methyl ether, Xa. Hydrogenation of Xa (step 7) followed by demethylation (step 8) gives df-equilenin XII, which on resolution affords d-equilenin, identical with the natural product.