Versuche zur Synthese von Verbindungen der Steroidreihe

Summary Reduction of the ketal II of 7-keto-1,4-dimethoxy-4b-methyl-5, 6, 7, 9, 10-hexahydrophenanthrene with lithium in liquid ammonia furnishes a corresponding dihydro derivative, from which a tricyclic triketone, m.p. 121°, is obtained upon acid hydrolysis. This triketone is identical with the recently described antitrans-4b-methyl-1, 2, 3, 4, 4a, 4b, 5, 6, 7, 9, 10, 10-dodecahydro-phenanthrene-1, 4, 7-trione III and thus conforms to the stereochemistry of the natural steroids.