1,3-Dibromo-5,5-dimethylhydantoin → 11alpha-Acetoxy-estra-4,6-diene-3,17-dione

Participants

Reaction Conditions

Reaction Steps

48 ml of a 10% aqueous sodium acetate solution and, in portions, 22.3 g of 1,3-dibromo-5,5-dimethylhydantoin are added to 57 g of 3,11α-diacetoxy-estra-3,5-dien-17-one in 470 ml of N-methyl-2-pyrrolidinone while being cooled with ice. After 30 minutes, 16.7 g of sodium sulfite is added, it is stirred for 15 minutes at 0° C., then mixed with 20 g of lithium bromide and 16 g of lithium carbonate and stirred at 100° C. After 2 hours, the reaction mixture is added to ice/water. The precipitated product is suctioned off, dissolved in methylene chloride, washed neutral with water and dried. The crude product is recrystallized from 200 ml of ethyl acetate. 30 g of 11α-acetoxy-estra-4,6-diene-3,17-dione with a melting point of 246-248° C. is obtained.

Provenance & Evidence