Cyclohexanone → 13-Ethinyl-17beta-hydroxy-10-methyl-gon-4-en-3-one

Participants

Reaction Steps

A solution of 900 mg of the crude 13-ethinyl-10-methyl-gon-5-ene-3β,17β-diol, obtained according to Example 2E, and 540 mg of aluminium isopropylate in 135 ml of toluene and 5.4 ml of cyclohexanone is boiled under reflux, under a water separator, for 60 minutes. After cooling, the reaction mixture is diluted with ethyl acetate, washed with potassium sodium tartrate solution, water and saturated sodium chloride solution, dried and evaporated. The oily residue is chromatographed on 80 g of silica gel. Using a mixture of hexane/ethyl acetate (3:1), 13-ethinyl-10-methyl-gon-4-ene-3,17-dione is eluted, melting point 148°-150° C; [α]D25 = +63°, after which 13-ethinyl-17β-hydroxy-10-methyl-gon-4-en-3-one, melting point 147°-149° C, [α]D25 =+154°, is obtained by elution with a mixture of the same solvents in a ratio of 2:1.

Provenance & Evidence