PREPARATION AND CHEMISTRY OF 9BETA-ESTR-4-EN-3-ONES

Hydrogenation of 17α-substituted estra-4,9(10)-dien-3-ones gave the corresponding 9β-estr-4-en-3-one accompanied by the 10α isomer. Because of inherent strain, the 9β-estr-4-en-3-ones readily isomerized under mild acid or base conditions to yield the analogous 9β-estr-5(10)-en-3-ones; more vigorous conditions resulted in epimerization to the 9β,1Oα-estr-4-en-3-ones. Reduction of 17β-hydroxy-17α-methyl-9β-estr-4-en-3-one with Li-NH3 yielded 17β-hydroxy-17α-methyl-5α,9β,lOβ-estran-3-one. © 1969, American Chemical Society. All rights reserved.