Oxalic Acid → Gestodene

Participants

Reaction Conditions

Reaction Steps

At 0° C., acetylene is introduced for 15 minutes into a solution of 40 ml of n-butyllithium (15% in hexane) in 100 ml of absolute tetrahydrofuran and then 4.0 g of 3-methoxy-18-methyl-3,5,15-estratrien-17-one in 40 ml of tetrahydrofuran is added dropwise thereto. After 15 minutes, the mixture is combined with 8 ml of water, 40 ml of methanol and 8 g of oxalic acid, stirred for one hour at 60° C., 600 ml of water is added, and the mixture is extracted with ethyl acetate. The organic phase is washed with water and dried. Recrystallization from ethyl acetate yields 2.4 g of 17α-ethynyl-17β-hydroxy-18-methyl-4,15-estradien-3-one. Melting point 197° C.

Provenance & Evidence