Heptanoyl chloride → 11beta-Fluoro-17beta-heptanoyloxy-7alpha-methylestr-4-en-3-one

Participants

Reaction Steps

A solution of 220 mg of 11β-fluoro-17β-hydroxy-7α-methylestr-4-ene-3-one (I) in 5 ml of tetrahydrofuran and 1.09 ml of pyridine was mixed drop by drop at 0° C. with 1.09 ml of heptanoyl chloride and stirred for 1 hour. Then, it was mixed with sodium bicarbonate solution, extracted three times with ethyl acetate, washed neutral, dried on sodium sulfate, concentrated by evaporation in a vacuum and chromatographed on silica gel with hexane/ethyl acetate. 210 mg of pure 11β-fluoro-17β-heptanoyloxy-7α-methylestr-4-en-3-one (I′) was obtained as a foam ([α]D20=+40.8° (c=0.56% in chloroform)).

Provenance & Evidence