Sulfuric Acid → (3beta,5beta,15alpha,16alpha)-15,16-Dihydro-3,5-dihydroxy-3'H-cycloprop(15,16)androsta-6,15-dien-17-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

5-Hydroxy-15β,16β-methylene-3β-pivaloyloxy-5β-androst-6-en-17-one (80.00 g, 0.200 mol) is suspended under nitrogen in tetrahydrofuran (800 mL), mechanically stirred and cooled to 0-2° C. A solution of potassium hydroxide (85%, 27.69 g, 0.419 mol) in methanol (410 mL) is added dropwise below 5° C. followed by sodium perchlorate monohydrate (7.85 g, 0.056 mol). The mixture is stirred at room temperature for 3-4 hours. After cooling to 4-5° C., water (400 mL) is added followed by 20% sulfuric acid in water (90 mL) adjusting the pH to 7 and the mixture is stirred for 10-15 minutes. Tetrahydrofuran and methanol are then removed at 40° C. under reduced pressure and the residue is diluted with water (300 mL). The suspension is stirred at 5° C. for 30 minutes and the solid is filtered, washed with water and dried at 45° C. in a vacuum oven for 16 hours. The title compound is obtained as a colourless solid (61.00 g, 0.192 mol, 97%) and is used in the next step without purification.

Herkunft & Nachweise