Potassium Carbonate → 1-Acetoxy-16alpha-bromo-3-methoxyestra-1,3,5(10)-trien-17-one

Participants

Reaction Steps

A solution of Br2 (0.4 g, 2.5 mM) in 10 ml of carbon tetrachloride is added over a period of 5 min to a suspension of 1,17-diacetoxy-3-methoxyestra-1,3,5(10),16-tetraene (0.95 g, 2.5 mM), potassium carbonate (0.53 g) and 40 ml of carbon tetrachloride at 0°. After an additional 5 min the colorless suspension is added to a solution of NaHSO3 (1 g) in 75 ml of H2O. The layers are separated and the aqueous layer is extracted with 3 × 25 ml of chloroform, the organic layers are combined and evaporated in vacuo after drying with MgSO4. Trituration of the residue with a small amount of methanol gives 1-acetoxy-16α-bromo-3-methoxyestra-1,3,5(10)-trien-17-one, yield 0.94 g (90%); m.p. 188°-190° (methanol).

Provenance & Evidence