p-Toluenesulfonic acid → 11beta-Fluoro-17beta-(4-sulfamoylbenzoxy)-7alpha-methylestr-4-en-3-one

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Reaction Steps

A solution of 500 mg of 11β-fluoro-17β-hydroxy-7α-methylestr-4-en-3-one in 7.5 ml of pyridine was mixed at room temperature with 750 mg of 4-sulfamoylbenzoic acid, 800 mg of N,N-dicyclohexylcarbodiimide as well as 125 mg of p-toluenesulfonic acid and stirred for 8.5 hours. Then, it was added to sodium bicarbonate solution, extracted four times with dichloromethane, washed neutral, dried on sodium sulfate, concentrated by evaporation in a vacuum, and chromatographed on silica gel with dichloromethane/acetone. 302 mg of 11β-fluoro-17β-(4-sulfamoylbenzoxy)-7α-methylestr-4-en-3-one with a melting point of 232° C. was obtained. [α]D=+100.5° (CHCl3).

Provenance & Evidence