p-Toluenesulfonic acid → HCID 14462265, compound

Participants

Reaction Conditions

Reaction Steps

Acetic anhydride (80 ml) and p-toluene sulfonic acid (6 g) are added to a suspension of 3-methoxy-16-methylestra-1,3,5(10),15-tetraen-17-one (1) (DE-OS 3,023,568 (1982)) (20 g; 67.7 mmol) in isopropenyl acetate (400 ml). The reaction mixture is stirred for about 20 hours at 100° C. After cooling it is poured on ice water and neutralized by addition of small portions of sodium bicarbonate. It is extracted three times with benzene, the combined organic phases are washed with water, dried on magnesium sulfate and concentrated by evaporation in a vacuum. The resulting brown residue (23.5 g) is chromatographed on silica gel with a mixture of ethyl acetate/benzene (1:49). The yellowish crystalline productis further purified by recrystallization of ethyl acetate/methanol. 19.8 g (87%) of colorless 14,16-diene-17-acetate (2) is obtained.

Provenance & Evidence