A solution of 20 g of desoxycorticosterone in 190 ml of absolute ethanol was
stirred in an atmosphere of hydrogen in the presence of 1.68 g of 25%
palladium on calcium carbonate catalyst. After 20 hours, approximately 1
molar equivalent of hydrogen had been absorbed and hydrogen uptake had
ceased. The catalyst was removed by filtration and the filtrate evaporated in
vacuo to yield 20 g of nearly pure product, MP 135°C to 140°C. The crude
product was demonstrated to be free of starting material by paper
chromatography. A highly purified product was obtained by recrystallization
from acetone-water with cooling in an ice bath, yield 14.5 g, MP 152°C to
154°C. The product was characterized by analysis and by absence of
ultraviolet absorption.
A solution of 14 g of 21-hydroxypregnane-3,20-dione and of 14 g of
recrystallized succinic anhydride in 140 ml of dry pyridine was allowed to
stand at room temperature for 18 hours, then cooled in an ice bath and
poured in a fine stream into 1.5 liters of ice water. Excess pyridine was
neutralized with 3N hydrochloric acid and the solution further diluted with 2
liters of ice water. The precipitated product was filtered, washed with water
and dried in vacuo at 50°C affording 18 g of solid MP 192°C to 195°C.
Recrystallization of a small sample afforded analytically pure material, MP
200°C.
