Water → 4-Androstene-3,17-dione, 1alpha-methyl-

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Reaction Conditions

Reaction Steps

2.84 g (10 mmol) of androsta-1,4-diene-3,17-dione is dissolved in 20 ml of anhydrous dioxane under nitrogen atmosphere. 143.3 mg (1 mmol) of copper(I) bromide is added and the solution is heated to 25° C. Then 9.4 ml (11 mmol) of a 10% solution of trimethyl aluminum in toluene is added to the reaction so that the temperature does not rise above 35° C. Then it is stirred for 1.5 hours more at 35° C. For hydrolysis, 0.54 ml of water mixed with 5 ml of dioxane is carefully added to the reaction and the solution is stirred for 15 minutes more. The inorganic solid is suctioned off and washed again with 30 ml of dioxane. After concentration by evaporation of the solution, 3.1 g of 1α-methylandrost-4-ene-3,17-dione is obtained, that is dissolved in 8 ml of methanol and cooled to -5° C. internal. temperature. 0.18 g of sodium borohydride is added to 0.5 ml of water cooled to 5° C. and the sodium borohydride-water solution is added to the solution of 1α-methyl-androst-4-ene-3,17-dione so that the temperature does not rise above -5° C. Then it is stirred for 40 minutes more at -5° C. After DC check to determine whether the reaction has occurred, 0.33 ml of acetic acid in 1 ml of water is carefully added until no more gas generation is detectable. The solution is taken up in 50 ml of ethyl acetate and washed twice with 20 ml of water each. The organic phase is dried with sodium sulfate. After concentration by evaporation of the solution and recrystallization from acetone, 2.29 g of 17β-hydroxy-1α-methyl-androst-4-en-3-one (75% of theory) of a melting point of 195° C. is obtained.

Provenance & Evidence