abstract |
A method for the production of 3-keto Δ 4,6-6-trifluoromethyl steroids and 3-keto- Δ 1,4,6-6-trifluoromethyl steroids of the androstane series, of the 19-nor-androstane series , and of the pregnane series, and the 19-nor-pregnane series, characterized in that the 3-keto- Δ 4-6- α -trifluoromethyl steroid of one of said series, in which the group of 3- keto has been transformed into a cyclic ketal group is reacted with N-bromosuccinamide, in which the reaction product is dehydrobrominated and subsequently the ketal group is removed by acid hydrolysis after which if it is desired to achieve a 3-ketocyte steroid Δ 1,4,6-6-trifluoromethyl, the 3-keto- Δ 4,6-6-trifluoromethyl steroid thus obtained is dehydrogenated in the manner known per se. (Machine-translation by Google Translate, not legally binding) |