Ethyl Acetate → 6alpha-Fluoro-9alpha-bromo-11beta-hydroxy-16beta-methyl-17alpha,21-diacetoxypregna-1,4-diene-3,20-dione

Participants

Reaction Steps

Ten (10) g of 6α-fluoro-16β-methyl-17α,21-diacetoxypregna-1,4,9(11)-triene-3,20-dione in 110 ml of dioxane (A.R.) plus 2.2 mls of a solution of 4.4 ml 70% HClO4 in 200 mls of water, is treated with 4 g of dibromohydantoin in the dark at R.T. for a period of one hour or when TLC using 50% ethyl acetate/50% hexane shows the reaction to be complete. The reaction mixture is precipitated in 2 of water, stirred for 10 minutes and the crystalline precipitate collected by filtration, washed with water, and air dried to give 11.4 g of 6α-fluoro-9α-bromo-11β-hydroxy-16β-methyl-17α,21-diacetoxypregna-1,4-diene-3,20-dione.

Provenance & Evidence