1,3-Dibromo-5,5-dimethylhydantoin → 11beta-Fluoroestra-4,6-diene-3,17-dione

Participants

Reaction Conditions

Reaction Steps

5 ml of a 10% sodium acetate solution and, in portions, 2.5 g of 1,3-dibromo-5,5-dimethylhydantoin are added in succession to 5.0 g of 11β-fluoro-3-methoxy-estra-3,5-dien-17-one in 50 ml of DMF at 0° C. After 30 minutes, 2.3 g of sodium sulfite and then 2.5 g of lithium bromide and 2.0 g of lithium carbonate are added and stirred for 2 hours at 100° C. The reaction mixture is stirred into ice water. The precipitated product is suctioned off, dissolved in ethyl acetate, washed with water, dried and concentrated by evaporation in a vacuum. After recrystallization from ethyl acetate, 3.6 g of 11β-fluor-estra-4,6-diene-3,17-dione with a melting point of 198° C. is obtained.

Provenance & Evidence