Tetrahydrofuran → (7-alpha,17 beta)-17-(Acetyloxy)-7-propylestr-4-en-3-one

Participants

Reaction Steps

After stirring for an additional 0.5 hr , a solution of 5.2 g of (17 beta)-17-(acetyloxy)estra-4,6-dien-3-one (1) in 20 ml of THF was added dropwise at −40 C. Upon stirring for an additional 15 minutes the reaction was complete, and the mixture was poured onto 300 ml of saturated NH4Cl solution, followed by extraction with ethyl acetate. The organic material, isolated after washing, drying and evaporation of the solvent, was taken up in 30 ml of THF and stirred in the presence of 3 ml of 6N H2SO4 to isomerize some Δ5,6 isomer to Δ4,5 isomer. After 1 hr the mixture was neutralized with saturated NaHCO3 solution and extracted with ethyl acetate. Chromatography of the crude product over silica gel (heptane/ethyl acetate 8/2) provided 2.1 g of 2, m.p. 97-100° C.

Provenance & Evidence