aqueous layer was extracted with 700 ml. of chloroform and the chloroform extracts were combined and washed with 1350 ml. of water. The chloroform solution was concentrated under reduced pressure to a volume of 450 ml. The mixture was cooled to 0-5 °. To the slurry was added slowly 3150 ml. of petroleum ether, the temperature being maintained at 0-5°. After stirring for one hour, the ketol III was collected on a filter, washed with a mixture of petroleum ether and chloroform (4:1), finally with petroleum ether and dried in air at 60°; yield 83.5 g. (90.7%), m.p. 229-231°, [ ] 79°( c 1, acetone).Essentially pure material was obtained by stirring the product with a mixture of 210 ml. of isopropyl alcohol and 210 ml. of absolute ether at 20-25°for 30 minutes and then at 0-5°for 30 minutes. The purified ketol was collected and washed with 82 ml. of absolute ether; weight 73.8 g. (recovery 88.4%, over-all, 80%), m.p. 232.5-234.5°, [<*]26d 82.3°( c 1, acetone).Pregnane-l7a,21-diol-3,ll,21-trione 21-Acetate ( ) from IV.-Ten grams (0.025 mole) of the isomeric cyano-pregnane6 IV (m.p. 132-134°) oxidized according to the above procedure, yielded 7 g. (69%) of III, m.p. 232-234°. The ketol was isolated from a mixture of petroleum ether and chloroform with ratio of 3 to 1 instead of 7 to 1, thus the purification step was unnecessary.Pregnane-3a,17a,21-triol-ll,20-dione 3,21-Diacetate (VI) from V.-From 11.1 g. (0.052 mole) of A17-20-cyanopregnene-3a,21-diol-ll-one diacetate (V)1 there was obtained 8.43 g. (74.6%) of the corresponding ketol VI; m.p. 237-238°. No melting point depression was observed when mixed with an authentic sample of VI.Pregnane-3ar,17a,21-triol-ll,20-dione 21-Acetate (VIII).-Five grams of Al7-20-cyanopregnene-3a,21-diol-ll-one 21acetate (VII)1 was treated with potassium permanganate in the manner described previously. The triol 21-acetate VIII was obtained in 75% yield; m.p. as the melting point of VIII is not depressed by admixture with III, it was necessary to convert it into the 3,21diacetate, m.p. 232-235°, by treatment with acetic anhydride in pyridine (93% yield). The structure of the resulting 3,21-diacetate was confirmed by mixed melting point determinations with samples of III and VI. As expected, admixture with III showed depression while the mixture of diacetate with VI showed no depression.Oxidation of A17-20-Cyanopregnene-3a,21-diol-ll-one (IX).-Five grams of IX was treated with potassium permanganate in the usual manner. An oil was obtained which was acetylated to give a semi-crystalline product from which no 3a,21-diol diacetate was isolated.Pregnane-11 (3), 17(a),21-triol-3,20-dione 21-Acetate (XI).-From 3.12 g. of Al7-20-cyanopregnene-ll(3),21-diol-3-one 21-acetate7 (X) there was obtained 2.28 g. of crude XI; m.p. 198-205°. Recrystallization of the crude material from acetone-petroleum ether gave 1.24 g. (39%) of XI; m.p. 218-220°-no melting point depression with an authentic sample of XI.
